FLY ASH FLY ASHFLY ASHFLY ASHFLY ASHFLY ASHFLY ASH

Fly Ash Applicability in Pervious Concrete

Thesis

Presented in Partial Fulfillment of the Requirements for the Degree Master of Science in
the Graduate School of The Ohio State University

By
Na Jin, B. E.
Graduate Program in Civil Engineering

The Ohio State University
2010

Thesis Committee
William E. Wolfe, Advisor
Fabian Hadipriono Tan
Tarunjit Singh Butalia

Copyright by

Na Jin
2010

2

ABSTRACT
Pervious concrete has been used in the United State for over 30 years. Because of
its high porosity, the most common usages have been in the area of stormwater
management, but have been limited to use in pavements with low volume traffic because
of its low compressive strength compared to conventional concrete. Fly ash has been
shown in numerous post studies to increase the strength and durability of conventional
concrete. In this study, six batches of pervious concrete with different amounts of
aggregate, cement, and fly ash were prepared to find the mix that generated high
compressive strength and study the effect of fly ash on the compressive strength and
permeability of pervious concrete.
Materials used in this study were selected based on literature reviews and
recommendations from local sources. Unconfined compressive strength tests were carried
out on pervious concrete specimens with fly ash contents of 0%, 2%, 9%, 30%, 32% by
weight of the total cementitious materials. Falling head permeability tests were carried
out on specimens having 2% and 32% fly ash.
The results indicated the pervious concrete containing 2% fly ash can achieve
compressive strength greater than 3,000 psi at void content of 12%, and a compressive
strength 2,300 psi with a permeability of 0.13 cm/s at a void content of 15%. The
pervious concrete with 32% fly ash had a compressive strength of 2,000 psi and the
permeability of 0.21 cm/s at a void content of 15.8%. The failure surfaces of specimens
ii

with 2% fly ash developed through the coarse aggregates, indicating the high strength of
cement bonds. The failure of specimens containing 32% fly ash was observed to be along
the coarse aggregates surfaces, indicating a lower strength of the paste. Although it was
expected for pervious concrete with 32% fly ash to reach a higher compressive strength at
lower void content, the failure mode indicated that it may not reach the value as high as
that of pervious concrete with 2% fly ash at the same void content.

iii

DEDICATION

Dedicated to my dear parents and husband.

iv

ACKNOWLEDGEMENTS

I would like to express my sincere appreciation to my advisor, Dr. William E.
Wolfe, for his guidance, patience, kindness, and encouragement throughout this work. I
would also like to thank Dr. Fabian Hadipriono Tan for his suggestions and endless
support to me during my study. Without their help, the fulfillment of my master degree
would have been impossible.
I would also like to thank Dr. Tarunjit Singh Butalia for his suggestions and help
in facilitating the purchase of experimental equipments in this study. I am also grateful to
all of the professionals for their expertise, support, and kindness: Mr. Mark Pardi, is of
Ohio Concrete, gave me valuable suggestions and guidance on pervious concrete; Mr.
Dan Hunt, is of Buckeye Ready-Mix, carried out one example mix test on pervious
concrete and shared his valuable experience; Mr. Michael Adams, is of Euclid Chemical
Corp., provided with pervious concrete admixtures; Mr. Thomas J. Wissinger, is of the
Olen Corp., provided and delivered coarse aggregates even in bad weather; Mr. Dan Jahn,
is of Anderson Concrete, arranged a visit to the concrete company and provided with
portions of perivous concrete components.

v

VITA

1998 – 2002…………………. B. E, Construction Engineering, University of Science and
Technology of Suzhou
2002 – 2004………...… Zhenjiang Architectural Design & Research Institute, P.R. China
2004 – 2006….…………………….. Guangsha Architectural Design Institute, P.R. China
2008 – Present………………………...…. ..Civil Engineering, The Ohio State University

Fields of Study
Major Field: Civil Engineering

vi

Table of Contents
ABSTRACT………………………………………………………………………………ii
DEDICATION……………………………………………………………………………iv
ACKNOWLDEGEMENTS……………………………………………………………….v
VITA……………………………………………………………………………………...vi
List of Figures……………………………………………………………………………..x
List of Tables……...………………………………………………………………...…..xiii
CHAPTER 1: INSTRODUCTION ...............................................................................1
1.1 Background............................................................................................................1
1.2 Objectives..............................................................................................................2
1.3 Organization ..........................................................................................................3
CHAPTER 2: LITERATURE REVIEW OF PORTLAND CEMENT PERVIOUS
CONCRETE ..................................................................................................................5
2.1 Introduction ...........................................................................................................5
2.2 Benefits and Problems ...........................................................................................6
2.2.1 Benefits...........................................................................................................6
2.2.2 Problems .........................................................................................................8
2.3 Components of Pervious Concrete .......................................................................11
2.3.1 Coarse Aggregate..........................................................................................11
2.3.2 Fine Aggregate..............................................................................................12
2.3.3 Cement..........................................................................................................12
2.3.4 Fly Ash .........................................................................................................13
2.3.5 Water ............................................................................................................13
2.3.6 Admixtures ...................................................................................................14
2.4 Important Properties of Pervious Concrete ...........................................................16
2.4.1 Permeability ..................................................................................................16
2.4.2 Compressive Strength....................................................................................20
2.4.3 Freeze-thaw Durability..................................................................................21
2.4.4 Modulus of Elasticity ....................................................................................24
vii

2.5 Factors Affect Compressive Strength and Permeability of Pervious Concrete.......24
2.5.1 Effect of Void Content ..................................................................................25
2.5.2 Effect of Aggregate .......................................................................................27
2.5.3 Effect of Aggregate/Cement Material Ratio...................................................28
2.5.4 Effect of Water/Cement Ratio .......................................................................28
2.5.5 Effect of fly ash.............................................................................................29
2.5.6 Effect of Compaction Energy ........................................................................29
2.5.7 Effect of Fibers .............................................................................................31
2.5.8 Effect of Other Factors ..................................................................................32
2.6 Standard Test Methods.........................................................................................33
2.7 Pervious Concrete Design ....................................................................................34
2.7.1 Pervious Concrete Mix Design ......................................................................34
2.7.2 Pervious Concrete Pavement Hydraulic Design .............................................36
2.7.3 Pervious Concrete Pavement Structural Design .............................................37
CHAPTER 3: LITERATURE REVIEW OF FLY ASH............................................44
3.1 Introduction of Coal Combustion Products (CCPs) ..............................................44
3.2 Introduction of Fly Ash ........................................................................................47
3.2.1 Properties of Fly Ash.....................................................................................48
3.2.2 Class C and Class F Fly Ash..........................................................................48
3.2.3 Utilization of Fly Ash in Concrete .................................................................48
3.2.4 Environmental Benefits of Fly Ash Use.........................................................50
3.3 Effect of Fly Ash on Concrete..............................................................................51
3.3.1 Thermal Cracking .........................................................................................51
3.3.2 Compressive Strength....................................................................................51
3.3.3 Durability......................................................................................................53
3.3.4 Permeability ..................................................................................................54
3.3.5 Sulfate Attack ...............................................................................................55
3.4 Fly Ash in Pervious Concrete...............................................................................56
3.5 Summary .............................................................................................................56
CHAPTER 4: LABORATORY MIX AND TEST .....................................................59
4.1 Introduction .........................................................................................................59
4.2 Mix Preparation ...................................................................................................59
4.2.1 Mix Materials................................................................................................59
4.2.2 Mix Design ...................................................................................................65
4.2.3 Mixing Equipment ........................................................................................71
4.2.4 Specimen Mold .............................................................................................74
4.3 Mixing Procedure ................................................................................................74
4.4 Compaction Method.............................................................................................75
4.5 Curing Method.....................................................................................................76
4.6 Laboratory Tests ..................................................................................................77
4.6.1 Unit Weight and Void Content ......................................................................77
viii

4.6.2 Compressive Strength....................................................................................79
4.6.3 Permeability ..................................................................................................80
4.7 Summary of Test Procedure .................................................................................83
CHAPTER 5: DISCUSSION ON TEST RESULTS ..................................................86
5.1 Introduction .........................................................................................................86
5.2 Void Content vs. Unit Weight ..............................................................................86
5.3 Effect of Compaction Energy ...............................................................................87
5.4 Effect of W/C Ratio, A/C Ratio and Fly Ash on Void Content .............................90
5.5 Compressive Strength ..........................................................................................90
5.5.1 Compressive Strength vs. Curing Period........................................................91
5.5.2 Compressive Strength vs. Void Content ........................................................92
5.5.3 Compressive Strength vs. Unit Weight ..........................................................94
5.5.4 Compressive Stress-strain Curves vs. Void Content.......................................94
5.5.5 Compressive Failure vs. Curing Period..........................................................98
5.5.6 Failure Modes ...............................................................................................99
5.6 Permeability.......................................................................................................103
CHAPTER 6: SUMMARY, CONCLUSION, AND RECOMMENDATIONS.......107
6.1 Summary ...........................................................................................................107
6.2 Conclusion.........................................................................................................109
6.3 Recommendations for Future Work....................................................................111
REFERENCES ..........................................................................................................113
APPENDIX A: EXAMPLES OF PERVIOUS CONCRETEEXPERIMENTS FROM
LITERATURE REVIEWS .......................................................................................121
APPENDIX B: PROPERTIES OF PERVIUOS CONCRETE COMPONENTS ...125
APPENDIX C: LABORATORY TEST RESULT ...................................................137
APPENDIX D: PERVIOUS CONCRETE MIX DESIGN PROGRAM CODE .....168

ix

List of Figures
Figure 2.1. Model Resulting from the Nonlinear Fitting of the Saturated Hydraulic
Conductivity and Total Porosity Data to the Carman-Kozeny Equation .........................18
Figure 2.2. Plot of the Ergun Equation and Values Calculated Using the Falling Head
Experimental Data from Samples Calculated with Dp = 0.1, Dp = 0.3, and Dp =
0.6.(adapted from Montes and Haselbach ).....................................................................19
Figure 2.3. Relationship between Strength, Void Content and Permeability for Several
Trial Mixes of Portland Cement Pervious Concrete........................................................26
Figure 2.4. Nomograph to Determine Structural Number (Pavement Strength) .............38
Figure 3.1. Uses of Coal Combustion Products in 2008 (AACA adapted from U. S
Environmental Protection Agency (EPA)) .....................................................................45
Figure 3.2. 1966-2007 CCP Beneficial Use vs. Production (AACA) ..............................46
Figure 3.3. Coal Combustion Products Generation and Use (Short Tons) (AACA adapted
from EPA) .....................................................................................................................47
Figure 3.4. Top Uses of Coal Fly Ash 2003 (AACA adapted from)................................49
Figure 3.5. Comparison between Ash Concrete Compressive Strength and Plain Cement
Concrete Compressive Strength. ....................................................................................52
Figure 3.6. Effect of Fly Ash on Permeability of Concrete (adapted from) .....................55
Figure 4.1. Grain Distribution Curve of Size Number 8 River Gravel (Olen Corp.)........61
Figure 4.2. Pervious Concrete Mix Calculation Program................................................68
Figure 4.3. 20 quart Blakeslee Mixer .............................................................................72
Figure 4.4. Specimen Mixed Using 20 Quart Blakeslee Mixer .......................................72
Figure 4.5. 3.4ft3 capacity Gilson 39555 (drum speed speed 22 ~ 25 RPM) ...................73
Figure 4.6. INSTRON-5585 Compressive Strength Testing Machine.............................80
Figure 4.7. Falling Head Permeability Test for Pervious Concrete Specimen .................82
Figure 4.8. Pervious Concrete Specimen for Permeability Test ......................................82
Figure 5.1. Relationship between Void Content (%) and Unit Weight (lb/ft 3).................87
Figure 5.2. Void Contents of Specimens Compacted by Different Methods ...................88
Figure 5.3. The Specimen Compacted by Proctor Hammer ............................................89
Figure 5.4. Pervious Concrete Mix #3~#6 Compressive Strength vs. Curing Period.......92
Figure 5.5. Relaiton between 28-day Compressive Strength and Void Content ..............93
Figure 5.6. Relationship between 28-day Compressive Strength and Unit Weight..........94
Figure 5.7. Stress-strain Curves Tested on Specimens with Different Void Content at 28day Curing Period, Mix #5.............................................................................................96
Figure 5.8. Stress-strain Curves Tested on Specimens with Different Void Content at 28day Curing Period, Mix #6.............................................................................................97
Figure 5.9. Stress-strain Curves Tested on Specimens with Void Content 18% at 7-day,
21-day, and 28-day Curing Periods, Mix #6 ...................................................................99
x

Figure 5.10. Failure Mode I of Pervious Concrete Samples..........................................100
Figure 5.11. Failure Mode II of Pervious Concrete Samples.........................................100
Figure 5.12. Failure of Specimen Compacted by Standard Proctor Hammer (Mix #6)..101
Figure 5.13. Failure Surface Comparison between Specimen from Mix #5 and Mix #6 102
Figure 5.14. Relationship between Void Content and Permeability of Pervious Concrete
Specimens ...................................................................................................................103
Figure 5.15. Comparison of Permeability Test Results with Previous Studies ..............106
Figure 6.1. Permeability and 28-day Compressive Strength vs. Void Content ..............109
Figure B.1. Properties of Coarse Aggregates................................................................126
Figure B.2. Properties of Cement (St. Marys) ..............................................................127
Figure B.3. Properties of High Range Water Reducer (Euclid Chemical Company) .....128
Figure B.4. Properties of Mid-Range Water Reducer (Euclid Chemical Company) ......130
Figure B.5. Properties of Mid-Range Water Reducer (Euclid Chemical Company) ......132
Figure B.6. Properties of Viscosity Modifying Admixture (Euclid Chemical Company)
....................................................................................................................................134
Figure B.7. Properties of Fiber (Euclid Chemical Company)........................................135
Figure C.1. 11-day Compressive Stress-strain Curve of Specimen with Void Contend of
31% from Mix #3 ........................................................................................................147
Figure C.2. 21-day Compressive Stress-strain Curve of Specimen with Void Contend of
31% from Mix #3 ........................................................................................................147
Figure C.3. 28-day Compressive Stress-strain Curve of Specimen with Void Contend of
31% from Mix #3 ........................................................................................................148
Figure C.4. 7-day Compressive Stress-strain Curve of Specimen with Void Contend of
27% from Mix #4 ........................................................................................................148
Figure C.5. 21-day Compressive Stress-strain Curve of Specimen with Void Contend of
27% from Mix #4 ........................................................................................................149
Figure C.6. 28-day Compressive Stress-strain Curve of Specimen with Void Contend of
27% from Mix #4 ........................................................................................................149
Figure C.7. 7-day Compressive Stress-strain Curve of Specimen with Void Contend of
12% from Mix #5 ........................................................................................................150
Figure C.8. 21-day Compressive Stress-strain Curve of Specimen with Void Contend of
12% from Mix #5 ........................................................................................................150
Figure C.9. 28-day Compressive Stress-strain Curve of Specimen with Void Contend of
13% from Mix #5 ........................................................................................................151
Figure C.10. 7-day Compressive Stress-strain Curve of Specimen with Void Contend of
17% from Mix #6 ........................................................................................................151
Figure C.11. 21-day Compressive Stress-strain Curve of Specimen with Void Contend of
18% from Mix #6 ........................................................................................................152
Figure C.12. 28-day Compressive Stress-strain Curve of Specimen with Void Contend of
18% from Mix #6 ........................................................................................................152
Figure C.13. 28-day Compressive Stress-strain Curve of Specimen with Void Contend of
16% from Mix #5 ........................................................................................................153
Figure C.14. 28-day Compressive Stress-strain Curve of Specimen with Void Contend of
15% from Mix #5 ........................................................................................................153

xi

Figure C.15. 28-day Compressive Stress-strain Curve of Specimen with Void Contend of
12% from Mix #5 ........................................................................................................154
Figure C.16. 28-day Compressive Stress-strain Curve of Specimen with Void Contend of
12% from Mix #5 ........................................................................................................154
Figure C.17. 28-day Compressive Stress-strain Curve of Specimen with Void Contend of
14% from Mix #5 ........................................................................................................155
Figure C.18. 28-day Compressive Stress-strain Curve of Specimen with Void Contend of
14% from Mix #5 ........................................................................................................155
Figure C.19. 28-day Compressive Stress-strain Curve of Specimen with Void Contend of
13% from Mix #5 ........................................................................................................156
Figure C.20. 28-day Compressive Stress-strain Curve of Specimen with Void Contend of
18% from Mix #6 ........................................................................................................156
Figure C.21. 28-day Compressive Stress-strain Curve of Specimen with Void Contend of
20% from Mix #6 ........................................................................................................157
Figure C.22. 28-day Compressive Stress-strain Curve of Specimen with Void Contend of
22% from Mix #6 ........................................................................................................157
Figure C.23. 28-day Compressive Stress-strain Curve of Specimen with Void Contend of
24% from Mix #6 ........................................................................................................158
Figure C.24. 28-day Compressive Stress-strain Curve of Specimen with Void Contend of
24% from Mix #6 ........................................................................................................158

xii

List of Tables
Table 2.1. NMCRA Classification of Regions and Recommendation of Precautions of
Utilizing pervious concrete ...........................................................................................22
Table 2.2. Compaction Method Conducted by Rizvi et al...............................................31
Table 2.3. Recommended Typical Mix Design by National Ready Mixed Concrete
Association....................................................................................................................35
Table 2.4. Recommended Typical Mix Design by the Southern California Ready Mix
Concrete Association (adapted from ) ............................................................................35
Table 2.5. Recommended Typical Mix Design by the Euclid Chemical Company .........35
Table 4.1. Physical Properties of #8 River Gravel (Olen Corp.) .....................................61
Table 4.2. Coarse Aggregate Distribution (Olen Corp.)..................................................61
Table 4.3. Chemical Properties of St. Marys Type I Cement (St. Marys, Inc.) ................63
Table 4.4. Physical Properties of fly ash ........................................................................64
Table 4.5. Admixtures from Euclid Chemical Company ................................................65
Table 4.6. Pervious Concrete Mix Design ......................................................................66
Table 4.7. Mix No. Corresponding to Mix ID. ...............................................................67
Table 4.8 Compaction Method ID Explanation ..............................................................75
Table 4.9. Pervious Concrete Mixes Compacted Using Different Methods Mix .............76
Table 4.10. Specific Gravities of Materials in Portland Cement Pervious Concrete Mix.79
Table A.1: Examples of Laboratory Tests on Pervious Concrete. .................................122
Table A.2. Examples of Field Projects of Pervious Concrete........................................124
Table C.1. Mix Design of Pervious Concrete Mix #1 ...................................................138
Table C.2. Unit Weight and Void Content of 4in x 8in Samples from Pervious Concrete
Mix #1.........................................................................................................................138
Table C.3. Mix Design of Pervious Concrete Mix #2 ...................................................139
Table C.4. Unit Weight and Void Content of 4in x 8in Samples from Pervious Concrete
Mix #2.........................................................................................................................139
Table C.5. Mix Design of Pervious Concrete Mix #3 ...................................................140
Table C.6. Unit Weight and Void Content of 4in x 8in Samples from Pervious Concrete
Mix #3.........................................................................................................................140
Table C.7. Mix Design of Pervious Concrete Mix #4 ...................................................141
Table C.8. Unit Weight and Void Content of 4in x 8in Samples from Pervious Concrete
Mix #4.........................................................................................................................141
Table C.9. Mix Design of Pervious Concrete Mix #5 ...................................................142
Table C.10. Unit Weight and Void Content of 4in x 8in Samples from Pervious Concrete
Mix #5.........................................................................................................................142
Table C.11. Unit Weight and Void Content of 3in x 6in Samples from Pervious Concrete
Mix #5.........................................................................................................................143
Table C.12. Mix Design of Pervious Concrete Mix #6 .................................................143
xiii

Table C.13. Unit Weight and Void Content of 4in x 8in Samples from Pervious Concrete
Mix #6.........................................................................................................................144
Table C.14. Unit Weight and Void Content of 3in x 6in Samples from Pervious Concrete
Mix #6.........................................................................................................................144
Table C.15. Compressive Strength of Specimens from Mix #1~#6 at 7, 21, and 28 Days
Curing Periods.............................................................................................................145
Table C.16. 28-day Compressive Strength of Specimens from Mix #1~#6 with Various
Void Content ...............................................................................................................146
Table C.17. Measured and Calculated Permeability of Pervious Concrete Specimens from
Literature Review ........................................................................................................159
Table C.18. Permeability Calculation Parameters in Falling Head Permeability Test ...161
Table C.19. Permeability Test Data for Specimen with Void Content of 19.5% from Mix
#5 ................................................................................................................................162
Table C.20. Permeability Test Data for Specimen with Void Content of 19.5% from Mix
#5 ................................................................................................................................162
Table C.21. Permeability Test Data for Specimen with Void Content of 17.0% from Mix
#5 ................................................................................................................................163
Table C.22. Permeability Test Data for Specimen with Void Content of 16.0% from Mix
#5 ................................................................................................................................163
Table C.23. Permeability Test Data for Specimen with Void Content of 14.9% from Mix
#5 ................................................................................................................................164
Table C.24. Permeability Test Data for Specimen with Void Content of 27.2% from Mix
#6 ................................................................................................................................164
Table C.25. Permeability Test Data for Specimen with Void Content of 25.0% from Mix
#6 ................................................................................................................................165
Table C.26. Permeability Test Data for Specimen with Void Content of 21.0% from Mix
#6 ................................................................................................................................165
Table C.27. Permeability Test Data for Specimen with Void Content of 21.5% from Mix
#6 ................................................................................................................................166
Table C.28. Permeability Test Data for Specimen with Void Content of 15.8% from Mix
#6 ................................................................................................................................166
Table C.29. Void Contents of Specimens Compacted at Different Compaction Methods
....................................................................................................................................167

xiv

CHAPTER 1
INTRODUCTION

1.1 Background
According to National Ready Mixed Concrete Association (NRMCA) 1 ,
“pervious concrete is a special type of concrete with a high porosity used for concrete
flatwork applications that allows water from precipitation and other sources to pass
through it, thereby reducing the runoff from a site and recharging ground water
levels.” It is also known as “no-fines concrete” and is composed of Portland cement,
coarse aggregate, water, admixtures, and little or no sand. In the past 30 years,
pervious concrete has been increasingly used in the United States, and is among the
Best Management Practices (BMPs) recommended by the Environmental Protection
Agency (EPA)2. By capturing stormwater and allowing it to seep into the ground,
pervious concrete is instrumental in recharging groundwater, reducing stormwater
runoff, and meeting U.S. EPA stormwater regulations. Other benefits of using
pervious concrete are: reduction of downstream flows, erosion and sediment;
reduction of large volumes of surface pollution flowing into rivers; decrease of urban
heat island effect; eliminating traffic noise; and enhancing safety of driving during
raining. The use of pervious concrete in building site design can also aid in the

1

process of qualifying the building for Leadership in Energy and Environmental
Design (LEED) Green Building Rating System credits2.
Due to the advantages of pervious concrete, the utilization and construction
properties of pervious concrete have been studied by many researchers 3,4,5,6 . The
characteristic of high permeability of pervious concrete contributes to its advantage in
storm water management. However, the mechanical properties such as compressive
strength are reduced due to this character, limiting the application of pervious
concrete to the roads that have light volume traffic.
The advantage of pervious concrete can be enhanced by substituting some of
the cement with other materials, such as fly ash. Fly ash is one of the by-products of
coal combustion in power generation plants. Large amount of fly ash are discarded
each year, increasing costs for disposal. On the other hand, fly ash has been shown to
improve the overall performance of concrete, when substituted for a portion of the
cement7. Hence, when fly ash is used in pervious concrete, the occupation of landfill
space can be reduced and CO emissions generated during cement production can be
2

decreased, improving the sustainability of pervious concrete.

1.2 Objectives
The objective of this research is to investigate the effects on the important
engineering properties of pervious concrete with the use of fly ash. The physical
properties examined include compressive strength and permeability of pervious
concrete. The parameters that affect the strength and the hydraulic conductivity of

2

pervious concrete will be analyzed. The potential use of pervious concrete containing
a large portion of fly ash will also be discussed.

1.3 Organization
This thesis consists of six chapters and four appendices. Chapter 1 is an
introduction of pervious concrete background and the study objectives. Chapter 2
presents literature reviews of pervious concrete, including benefits and problems, mix
designs, and properties of pervious concrete. Chapter 3 contains a brief literature
review of fly ash, introducing the application and effect of fly ash on concrete
properties. Chapter 4 introduces the laboratory mixing and laboratory tests, including
the selection of materials, mixing equipment, mix design, compaction method, and
test equipments. Chapter 5 elaborates on the test results, including void content,
compressive strength, and permeability of pervious concrete specimens. Chapter 6
summarizes the conclusions of the study, discusses the applicability of pervious
concrete that contains large amounts of fly ash, and provides with recommendations
for future work. Appendix A presents examples of pervious concrete experiments
taken from literature reviews. Appendix B illustrates the properties of pervious
concrete components used in this research. Appendix C presents the laboratory test
results. Appendix D shows codes of a program developed for pervious concrete mix
design.

1

NRMCA “CIP 38 – pervious concrete” brochure of National Ready Mixed
Concrete Association (NRMCA), <http://nrmca.org/aboutconcrete/cips/38p.pdf>
(Feb. 01, 2010).
3

2

National Ready Mixed Concrete Association (NRMCA),
<http://www.perviouspavement.org/index.html> (May 24, 2010).
3

Offenberg, M. (2008). “Is pervious concrete ready for structural applications?”
Structure Magazine, February, p. 48.

4

Johnston, K. (2009). “Pervious concrete: past, present and future.” Green
Building, Concrete Contractor,
<http://www.perviouspavement.org/PDFs/Concrete%20Contractor%20Mag%20%20PERVIOUS.Feb-Mar-09.pdf> (April. 24, 2010).
5

Schaefer, V. R., Suleiman, M. T., Wang, K., Kevern, J. T., and Wiegand, P.
(2006). “An overview of pervious concrete applications in stormwater
management and pavement systems.” < http://www.rmcfoundation.org/images/PCRC%20Files/Hydrological%20&%20Environmental%2
0Design/An%20Overview%20of%20Pervious%20Concrete%20Applications%20
in%20Stormwater%20Management%20and%20Pavement%20Systems.pdf> (Jun.
16, 2010).
6

Yang, J., and Jiang. G. (2003). “Experimental study on properties of pervious
concrete pavement materials.” Cement and Concrete Research, vol. 33, pp. 381386.
7

Headwaters Resources (2005). “Fly ash in pervious concrete.” Bulletin No. 29,
<http://www.flyash.com/data/upimages/press/TB.29%20Fly%20Ash%20in%20P
ervious%20Concrete.pdf > (May 21, 2010).

4

CHAPTER 2
LITERATURE REVIEW OF PORTLAND CEMENT PERVIOUS CONCRETE

2.1 Introduction
Offenberg3 stated that the first popular usage of pervious concrete was in postWorld War II England where it was used in two-story homes known as the Wimpey
Houses. During World War II, nearly two third of Britain’s houses had been
destroyed; and no new buildings had been constructed since 1939. Consequently, the
demand for housing was very high, causing a shortage of bricks. In this situation,
people were seeking alternate construction materials that were economical, reliable
and efficient. No-fine concrete was then used in some parts of the walls by Wimpey8
architects and engineers to decrease the cost.
In the United States, pervious concrete has been used for almost 30 years
since it was first introduced in California4. In order to study the factors influencing
the performance of pervious concrete, researchers have conducted experiments varing
mix proportions of cement, water, coarse aggregate, sand, fly ash, and admixtures.
According to experimental studies6,7,9,10,11,12,13 , researchers have found that factors
that affect the mechanical properties of pervious concrete are void content, aggregate
to cement ratio, fine aggregate amount, coarse aggregate size, coarse aggregate type,
compaction energy, and curing period.
5

2.2 Benefits and Problems
Due to the absence of fine aggregate, pervious concrete has high porosity,
which brings both benefits and drawbacks to construction.

2.2.1 Benefits
Since the pervious concrete pavement is permeable, water can be captured and
flow through the pavement during rainfall. In the mean time, free air is stored in the
pavement and allows the communication between the subsurface and the air. These
properties offer many advantages for pervious concrete.
2.2.1.1 Storm-water Management
One of the primary uses of pervious concrete is in storm water management.
Due to its high porosity, pervious concrete can capture stormwater and provide a path
for water to flow into the subsoil, helping to naturally adjust the ground water level.
Furthermore, instead of being carried into rivers and lakes by rain water, the residues
on pavement roads will be absorbed by pervious concrete or underneath soils, and
then degraded by microorganisms in soils2. Consequently, the pollution of water
resources could be decreased substantially, dramatically saving expense of storm
water management.
2.2.1.2 Heat Island Effect
Pervious concrete is much cooler than asphalt and conventional concrete. First
of all, the light color reflects more ultraviolet rays from sun and absorbs less heat than
6

asphalt. Secondly, the voids in pervious concrete allow it to store less heat than
conventional concrete does. This character benefits the districts in hot weather
climates. For instances, the group of National Center of Excellence for Sustainable
Materials and Renewable Technology at Arizona State University recommended the
utilization of pervious concrete for minimizing the urban heat-island effect14. Houston
Advanced Research Center (HARC) 15 published a report titled “Cool Houston! A
Plan for Cooling the Region,” in which the benefits of reducing heat island effect in
high density urban areas by using pervious concrete has been introduced.
2.2.1.3 Traffic Benefits
Pervious concrete shows several advantages on traffic. Firstly, the large
amounts of voids in pervious concrete are beneficial to reducing traffic noise. As
stated by Kim and Lee 16 , pervious concrete “is applied for sound barriers or
pavements to absorb traffic (tire) noise and reduce sound wave reflection”. To
investigate this property of absorption, Kim and Lee16 created a model to study the
acoustic absorption ability of pervious concrete, considering the gradation and shape
of aggregates and void content on pervious concrete pavement. The results calculated
by the modeling were compared with experimental and statistical results from
previous studies. All results illustrated that the maximum acoustic absorption ability
was increased with void content and was hardly affected by the shape of aggregate
when pervious concrete was compacted well. Secondly, pervious concrete enhances
the safety of driving during raining because of the elimination of ponding.

7

2.2.1.4 LEED
The usage of pervious concrete in building site design can also aid in the
process of qualifying for Leadership in Energy and Environmental Design (LEED)
Green Building Rating System credits. LEED was developed by the U.S. Green
Building Concil (USGBC). It provides a concise framework for identifying and
implementing practical and measurable green building design, and construction.
LEED for New Construction and Major Renovations version 2.2 has maximum total
of 69 points, in which concrete can earn up to 25 points. In addition, with the usage of
fly ash or other recycled materials in pervious concrete, up to 5 more credits could be
earned2.

2.2.2 Problems
High porosity is the necessary condition that makes pervious concrete
permeable, and is the main beneficial characteristic of pervious concrete. However it
can cause problems that limit the utilization of pervious concrete.
2.2.2.1 Compressive Strength
The bearing capacity of pervious concrete is decreased because of the
existence of large amounts of air voids. The low strength limits the utilization of
pervious concrete to parking-lots, side walks, and other low-volume traffic roadways.
Obviously, high porosity and strength are two incompatible features of pervious
concrete. This disadvantage initiates the study on pervious concrete aim to improve
its compressive strength while maintaining the relative high porosity.
8

2.2.2.2 Freeze-thaw Durability
The usage of pervious concrete in a freeze-thaw environment is also a concern,
especially in the northern area of the United States, which are districts experiencing
cold weather. The pervious concrete is more vulnerable to be destroyed under freezethaw weather. Research has been done to study the suitability of pervious concrete in
this type of climate. Regulations have been made to ensure the applicability of the
pervious concrete. For example ASTM C 666M-03 17 Standard Test Method for
Resistance of Concrete to Rapid Freezing and Thawing specifies the standard test
method to determine the resistance of concrete specimens to rapidly repeated cycles
of freezing and thawing in the laboratory following procedure A, Rapid Freezing and
Thawing in Water, and procedure B, Rapid Freezing in Air and Thawing in Water.
2.2.2.3 Abrasion
Abrasion of pervious concrete may limit its utilization. Raveling may happen
if aggregate is not sufficiently coated with cement paste. Other factors such as low
Water/Cement (W/C) ratio, dry weather, especially the rough surface also make
aggregate vulnerable to the abrasion. Theoretically, the abrasion of surface may make
surface more uneven and worsen abrasion over time. However, Hein and Schindler18
studied field projects constructed on the Auburn University campus, and found that
after curing of pervious concrete, about only 10% of surface aggregates were
displaced. But remaining surface was smooth enough as for a sidewalk and had
performed very well for three years.

9

2.2.2.4 Clogging Maintenance
Clogging is an unavoidable problem due to the existence of voids in pervious
concrete. The open voids are highly prone to be clogged during the utilization of
pervious concrete pavement over time. The U. S. EPA recommends that cleaning
need to be done regularly to prevent clogging2. Two methods of cleaning are
currently used: vacuum sweeping and high pressure washing. Even though cleaning is
performed regularly, not all contaminants are removed and the performance of
pervious concrete may lessen over the years. Moreover, the residues may cause
contamination of the water that runs through the pervious concrete. Hence,
stormwater testing is recommended in critical situations to preserve the quality of
ground water and inspect the permeability of pervious concrete.
2.2.2.5 Cost
Typically, the initial cost of pervious concrete is greater than that of
conventional concrete. However, because the lifespan of pervious concrete is longer
than that of the regular concrete2, some of the added cost is offset. The high initial
cost of pervious concrete is partly caused by the construction of the subgrade. A thick
layer of open gravel subgrade is usually installed under the pavement to provide the
storage and drainage of water. With such subgrade, pervious concrete normally can
perform very well even when built on clay soils. An example is presented by Dietz19,
who tested a subgrade of 10-in. thick layer of open graded gravel with undrained
system below. The subgrade showed good storage and drainage conditions. In general,
a thick layer of coarse aggregate “provides greater storage capacity and a longer time
10

allows water to exfiltrate to the native soils before underdarin flow would begin”19.
But the construction of subgrade increases the total cost of the pervious concrete
pavement. Another reason is the increased maintenance cost for pervious concrete
pavement after construction. As stated before, clogging problems need to be solved to
ensure the serviceability of pervious concrete.

2.3 Components of Pervious Concrete
Pervious concrete is mainly composed by coarse aggregate, cement, and water.
Small amount of fine aggregate may be added to obtain higher compressive strength.
Other admixtures such as High/Middle Range Water Reducer (HRWR, MRWR),
water retarder, viscosity modifying admixtures, and fibers are usually used. In some
cases, fly ash is used as a substitute for Portland cement to enhance the environmental
friendliness of pervious concrete.

2.3.1 Coarse Aggregate
Coarse aggregate is the main component of pervious concrete. The gradation,
size, and type of coarse aggregate have been found to affect the character of pervious
concrete6,9,10,11. In practice, river gravels that have size number of 8 (ASTM C 3320)
are widely used in construction. Other sizes of river gravels and limestone have been
used in laboratory tests to study the effect of coarse aggregate11.

11

2.3.2 Fine Aggregate
A fine aggregate is sometimes used in pervious concrete to improve the
mechanical capabilities of pervious concrete. On the other hand, the permeability will
typically decrease when fine aggregate is added. Wang et al.10 studied pervious
concrete with a fine aggregate amount of 7% of total aggregate by weight. Wang’s
tests illustrated that the compressive strength and freeze-thaw ability of pervious
concrete were significantly improved with addition of fine aggregate while
maintaining adequate water permeability. However, the amount of fine aggregate is
recommended to be limited within 7% of the total aggregate by weight so that
permeability is satisfied10.
According to the ASTM C 3320, the fine aggregate shall consist of natural or,
subject to approval, other inert materials with similar characteristics, or combinations
having hard, strong, durable particles. The amount substances such as clay lumps coal
and lignite, shale, and other deleterious substance should be limited within a range
individually, and the total amount should be less than 2% by dry weight. Soundness
loss should be less than 10% by weight. The fine aggregate should be free from
organic impurities.

2.3.3 Cement
Portland cement is another main component of pervious concrete. Type I/II
cement is normally used in pervious concrete9,10,11,12. The content of cement is
dependent on the amount and size of coarse aggregate and the water content. Various
12

amounts of cement are recommended by different agencies and will be introduced in
section 2.7.1.

2.3.4 Fly Ash
Fly ash can be used in pervious concrete as a substitute for a portion of the
cement. Two types of fly ash which are Class C and Class F fly ash are both able to
used in pervious concrete. Currently, fly ash can replace 5-65% of the Portland
cement2 in conventional concrete. However, according to the publication from
Headwaters Resources7, California Ready Mix Concrete Association (SCRMC)
recommended amount of ASTM C-618 fly ash is only 50-116lb/yd3 in pervious
concrete. The advantage of using fly ash is obvious: fly ash is a by-product of coal
burning in power plants, its utilization saves the energy required to produce the
cement. In addition, fly ash improves the flowability and workability of concrete.

2.3.5 Water
Water is a crucial component in pervious concrete. Wanielista and Chopra11
discussed the importance of adding appropriate amount of water in pervious concrete
mix. Enough water should be added so that cement hydration is thoroughly developed.
However, too much water will settle the paste at the base of the pavement and clog
the pores. Meanwhile, too much water increases the distance between particles,
causing higher porosity and lower strength. Wanielista and Chopra11 stated that “the
correct amount of water will maximize the strength without compromising the
permeability characteristics of the pervious concrete.”
13

2.3.6 Admixtures
Admixtures are sometime necessary for pervious concrete to obtain good
properties. Typical admixtures used in pervious concrete include HRWR, MRWR,
water retarder, viscosity modifying admixtures, air-entraining and fibers. The
admixtures should follow standards of ASTM C 494 21 (chemical admixtures) and
ASTM C 26022 (Air-entraining admixtures).
2.3.6.1 High/Middle Range Water Reducer
Based on experimental results, less water is used in pervious concrete than in
regular concrete2,9,18. One of the reasons is too much water causes settlement of
cement at the bottom resulting in clogging. To decrease the water content, a HRWR
or MRWR is often used. The dosages of water reducer used in pervious concrete are
various and should closely follow manufacturer’s recommendation.
2.3.6.2 Water Retarder
The National Ready Mixed Concrete Association reports that “because of the
rapid setting time associated with pervious concrete, retarders or hydration-stabilizing
admixtures are commonly used”2. Water retarder can extend setting time so that the
hydration of cement is fully developed.
2.3.6.3 Viscosity Modifying Admixtures
Compared to regular concrete, pervious concrete is very dry and hard to cast.
However with the usage of viscosity modifying admixtures, the workability can be
highly improved, and pervious concrete can be more manageable18. In a field project,
14

Hein and Schindler18 found that “The use of water reducing admixtures in
combination with viscosity modifying admixtures significantly reduced or eliminated
most of the previous difficulties experienced placing pervious concrete pavements”.
Since the usage of viscosity eliminated hard physical labor and improved the
smoothness and quality of pavement, Hein and Schindler claimed it as “a major
milestone in facilitating successful placement of quality pervious concrete
pavements”.
2.3.6.4 Air-entraining Admixtures
Air-entraining admixtures can be used in pervious concrete to improve its
freeze-thaw durability. Air-entraining admixtures can produce micro-closed air holes,
which can flexibly respond to the forces generated by freeze-thaw cycles. These
micro air bubbles are different from the voids in pervious concrete, which are open
holes and do not functional to sustain freeze-thaw forces.
2.3.6.5 Fibers
Fibers can be used in pervious concrete if higher compressive strength is
required. Experiments by Schaefer et al.23 showed that adding latex fibers increases
strength of pervious concrete; Yang and Jiang6 used organic polymer fibers and found
that they enhanced the strength of pervious concrete greatly. However, they typically
also cause a decrease in hydraulic conductivity.

15

2.4 Important Properties of Pervious Concrete
Permeability, compressive strength, freeze-thaw durability are important
properties of pervious concrete. They are affected by many factors such as water
content, void content, aggregate gradations, W/C ratio, and A/C ratio. Research has
been carried out to study the effect of different factors. In this research W/C ratio
stands for Water/total Cementitious Material ratio for simplification. A/C ratio stands
for total Aggregate/total Cementitious Materials ratio.

2.4.1 Permeability
High permeability is the primary characteristic of pervious concrete. Based on
previous studies 24,25,26,27 two permeability tests, the falling head tests and constant
head tests were both used to measure the hydraulic conductivity of pervious concrete
samples taken from sites or made in labs. Some lab testing also simulated the
conditions of pervious concrete in actual applications. Experimental and field tests
found that the typical permeability is larger than 0.1cm/sec or 140in/hour10, which is
considered as the lower limit of pervious concrete permeability.
McCain and Dewoolkar26 published a study on pervious concrete, in which
falling head permeability tests were carried out on three sets of specimens with
diameter 3 inches, 4 inches, and 6 inches, respectively. The falling head permeability
tests also simulated the situation of winter surface, which was covered by sand-salt
mixture. The results showed that the hydraulic conductivity ranged from 0.68cm/s to
0.98cm/s. One significant and special contribution of this article was the study on the
16

decrease of permeability by simulating the winter surface. The results illustrated 15%
average reduction on hydraulic conductivity. However, the permeability was still in
the allowable range (greater than 0.1cm/s).
Crouch et al. 27 used a triaxial flexible-wall constant head permeameter to
measure the permeability of pervious concrete in the range of 1 to 14,000 inches/hour
(0.001 to 10 cm/sec). Crouch et al. found the constant head permeability was a
function of three factors: effective air void content, effective void size, and drain
down, where “drain down is a result of too much paste for the applied compactive
effort or the paste being too fluid”, sealing the lower surface of pervious concrete
sample27.
Montes and Haselbach25 compared the hydraulic conductivity of pervious
concrete samples taken from three different field-placed slabs using a falling head
permeameter system. To investigate the factors affecting permeability of pervious
concrete, samples were collected with different W/C ratios and A/C ratios. Based on
previous studies7,24,25,26, the average porosity of the samples range from 15% to 30%
is typical for pervious concrete. The results indicated that the hydraulic conductivity
is dependent on the porosity. By comparing experimental results with the calculated
values from the equation, Montes and Haselbach25 studied the relationship between
porosity and hydraulic conductivity and found most fitted value of α=17.9 ± 2.3
(Figure 2.1) in the Carman-Kozeny equation: ks = α [p3/(1-p)2], where: ks = the
saturated hydraulic conductivity, p = porosity of pervious concrete (adapted from
Montes and Haselbach25). The effect of cementitious material and the non-spherical
shape of particles had been considered in this equation.
17

Figure 2.1. Model Resulting from the Nonlinear Fitting of the Saturated Hydraulic
Conductivity and Total Porosity Data to the Carman-Kozeny Equation25

Montes and Haselbach25 used the Ergun equation to analyze the flow
condition inside the pervious concrete samples. The Ergun equation has the form: f’ =
150/Re’+ 7/4, where f’ is a dimensionless friction factor, Re’ is a modified Reynolds
number which indicates the particular fluid porous media flow situation. The results
of Ergun model calculation presented for pervious concrete samples with various
porosities and saturated hydraulic conductivities were presented by Montes and
Haselbach25 (Figure 2.1). The trial results indicated that most of the samples were in

18

the laminar flow region. However, the flow regime may fall into the transition region
for higher porosity samples impacted by higher hydraulic head25.

Figure 2.2. Plot of the Ergun Equation and Values Calculated Using the Falling Head
Experimental Data from Samples Calculated with Dp = 0.1, Dp = 0.3, and Dp =
0.6.(adapted from Montes and Haselbach 25)
Note: Dp=0.1, 0.3, and 0.6cm can be interpreted as particles with different average
diameters and sphericities so that Dp would be equal to 0.1, 0.3, or 0.6 cm.

Montes and Haselbach25 established the equation between hydraulic
conductivity and porosity of pervious concrete sample as kS = 18 p3 / (1-p)2, which
show a high coefficient value between experiment and calculated results. However,
they also claimed the validation of the equation was for the pervious concrete samples
in that specific study, in which the size of aggregate was 3/8 inches ~ 5/8 inches, and
19

the porosity ranged from 15% to 32%. Although the application of equation is limited,
the study showed the flow regime in pervious concrete is in the laminar flow region,
in which Darcy’s law can be applied. This study is significant because it verified the
validation of Darcy’s law, which is assumed to be valid in most study of pervious
concrete permeability.
All articles stated above considered the permeability of pervious concrete in
freshly cast condition. Researchers rarely discussed the performance of pervious
concrete that had been used for a while or had become partially clogged. Haselbach et
al.24 studied the permeability of pervious concrete in partially clogged condition.
Considering the in-situ pervious concrete pavement, clogging is one of the important
concerns because it will decrease the porosity of pervious concrete, decreasing
permeability. In order to study the effect of clogging, Haselbach et al.24 started with
predicting the permeability of pervious concrete with formulas based on empirical
statistics and theoretical analysis. Then experiments were conducted to simulate the
rainfall and clogging situation, and the results were used to compare with predicted
values. The comparison showed good agreement between experimental results and
calculated values, verifying the validity of the prediction. The specialty of this
research is that it proposed models to predict the permeability of pervious concrete
under the worst condition of clogging, which is usually ignored in most research.

2.4.2 Compressive Strength
According to ASTM C 3928, a minimum compressive strength of 300psi is
required for pervious concrete. According to field and laboratory tests, pervious
20

concrete compressive strength regularly falls in a range of 400psi ~ 4,000psi (2.8MPa
~ 28MPa). But the common strength is from 600psi to 1,500psi (4MPa to 10MPa).
Laboratory studies have found compressive strength ranges from 600 psi to 3,600 psi
(4 MPa to 25 MPa)9,10,11.
Wanielista and Chopra11 summarized previous studies on compressive
strength of pervious concrete and stated that researchers agreed that factors affect
pervious concrete compressive strength included: A/C ratio, W/C ratio, coarse
aggregate size, compaction, and curing. “Researchers disagree as to whether pervious
concrete can consistently attain compressive strengths equal to conventional
concrete”.

2.4.3 Freeze-thaw Durability
Freeze-thaw durability is a crucial property to evaluate the suitability of
pervious concrete in cold weather. Freeze-thaw deterioration happens when concrete
is more than 91% saturated, which is generally true for concrete surfaces. When water
freezes, its volume will increase. The expansion of volume generates large pressures,
which act on concrete. When the pressure is in excess of the tensile strength of
concrete or mortar layer at a surface, cracking and scaling will occur.
Although some field projects indicated that pervious concrete performed well
in freeze-thaw situations, it must be used carefully in cold weather regions. The
NRMCA29 recommends the utilization of pervious concrete in different areas that
have various weather conditions. Table 2.1 shows the classification of different
districts and the suitability of using pervious concrete:
21

Precipitation Pervious
in Winter
concrete
little
no special
precaution

Pervious
concrete base
4 in to 8 in
thick, clean
aggregate

Region in
USA

Normal

no special
precaution

4 in to 8 in
thick, clean
aggregate

Many parts
of the
middle part
of the
Eastern U. S

Certain wet freeze areas
where the ground stays
frozen as a result of a long
continuous period of average
daily temperatures below
freezing

Precautions
required

8 in to 24 in
thick, clean
aggregate; airentraining
admixtures;
place PVC
pipe

Ground water level is less
than 3 ft from the top of
surface or where substantial
moisture can flow from
higher ground

Not
recommend

Region

Description

Dry freeze
and Hard
dry freeze

Annual
freeze-thaw
cycle: 15+

Wet
freeze

Annual
freeze-thaw
cycle: 15+

Hard wet
freeze

High
ground
water
table

Many parts
of the
Western U.
S

Table 2.1. NMCRA Classification of Regions and Recommendation of Precautions of
Utilizing pervious concrete 29

NRMCA29 suggests one method to improve the freeze-thaw resistant ability is
to entrain air. The microscopic entrained air bubbles that are evenly distributed in the
paste can help to relieve any pressure buildup. Generally for regular concrete, an air
entrainment of 4% ~ 8% can help to reach satisfactory performance in freeze-thaw
condition. However, no specific content has been investigated for pervious concrete.
In fact, the standard for conventional concrete is unsuitable to quantify the amount of
entrainment for pervious concrete29. Another method to improve the freeze-thaw
durability is to eliminate the saturation of pavement. By placing pervious concrete on

22

a thick layer of 8 to 24 inches (200 to 600mm) of open graded stone base, saturation
can be effectively avoided23.
In order to test the freeze-thaw resistance of pervious concrete, some
researchers did tests on saturated pervious concrete following procedure A, Rapid
Freezing and Thawing in Water of ASTM C 66617, requiring less than 5% mass loss
after 300 freeze-thaw cycles10. However, the fully saturated condition in procedure A
is very severe and not representative of field conditions 29 . Theoretically, partially
saturated pervious concrete performs well in freeze thaw region because the voids in
concrete can provide sufficient space for water to move. However, a fully saturated
condition may exist; and pervious concrete should be avoided in regions where this
situation is most likely to happen.
Schaefer et al.23 stated the failure mechanism of pervious concrete when
subjected to freeze-thaw cycles is either a result of aggregate deterioration or cement
paste matrix failure. Aggregate failure is seen by the deterioration or splitting of the
aggregate where a portion (usually 15%) of an aggregate particle becomes separated
from the concrete. Cement paste failure is observed by the raveling of entire pieces of
aggregate from the concrete. According to the experimental results presented by
Schaefer et al., “in general, mixes containing limestone (i.e. Mix 3/8-LS) failed by the
deterioration of the aggregate; however, mixes containing the smaller size No. 4 river
gravel failed due to aggregate deterioration and splitting”23.

23

2.4.4 Modulus of Elasticity
Dynamic modulus of elasticity is another important mechanical characteristic
of pervious concrete. The elastic modulus shows the resistance performance of
pervious concrete to fatigue, and is significant for evaluating the durability of
pavements, which is one of the most important indices to evaluate the perviousconcrete lifespan.
Crouch et al.9 tested the static moduli of four different pervious concrete
mixes with various aggregate sizes and gradations. The results showed that the static
elastic modulus was inversely proportional to the void content. And the optimum void
range which is from 23% to 31% happened in the mix with uniform gradation.
Crouch et al.9 found that the static elastic modulus decreased with increasing
aggregate and decreasing paste. No effect of aggregate sizes on static elastic modulus
has been shown.

2.5 Factors Affect Compressive Strength and Permeability of
Pervious Concrete
The compressive strength and permeability of pervious concrete have been
investigated and their relationships to void content were found. Higher void content
usually leads to higher permeability and lower compressive strength. Other factors
have also been found through experiments. These factors include aggregate, W/C
ratio, A/C ratio, fly ash, compaction energy9,23,27.

24

2.5.1 Effect of Void Content
Schaefer et al.23 studied effects of different proportions of mixture on the
properties of pervious concrete, and provided results to show the relationship between
strength, void content and permeability for several trial mixes of pervious concrete.
The experimental results showed that the permeability increased and compressive
strength decreased with increasing void content. The relationship is illustrated in
Figure 2.3. As shown, when the void content increased from 15% to 32%, the 7-day
compressive strength of pervious concrete decreased from 3,200psi to 1,300psi, while
the permeability increases from 50in/hour to 2,000in/hour. As can be seen in the
figure, the effect of void content on the measured permeability increased when the
void content increased from about 25% to 32%. Their tests showed that the increase
of permeability became more apparent when the void content was relatively large,
while the compressive strength as a function of void content remains linear.

25

Figure 2.3. Relationship between Strength, Void Content and Permeability for
Several Trial Mixes of Portland Cement Pervious Concrete23

Crouch et al.27 also studied the correlation between void content and
permeability in both laboratory and field cored specimens. The results showed
agreement with those from Schaefer et al.23. The average values illustrated high
strength of bond between void content and permeability with correlation coefficient
0.9737. In addition by comparing the laboratory results with experimental results
from prior studies, Crouch et al.27 found that the permeability at low void content
showed high consistency with the previous experimental results30,31 than those at high
void content. This indicated compressive strength values might be more consistent at
low void content.
Void content has been found as the primary factor that determines the
properties of pervious concrete. It was found to be determined from the concrete mix,
including amount of aggregate, cementitious materials, and water2.

26

2.5.2 Effect of Aggregate
The effect of aggregate on compressive strength and permeability of pervious
concrete comes from the coarse aggregate size, type, gradation, and the percentage of
fine aggregate.
2.5.2.1 Effect of Coarse Aggregate Type, Size and Gradation
Mulligan32 stated that since cement bond is limited in pervious concrete and
“the aggregate rely on the contact surfaces between one another, the aggregate with
higher stiffness such as granite or quartz would have higher compressive strength
than a softer aggregate such as limestone.
Besides the effect of aggregate type, the size of aggregate is another important
factor for compressive strength and permeability of pervious concrete. Yang and
Jiang6 conducted experiments on pervious concrete mixes having various aggregate
sizes. The results showed that the compressive strength was improved by decreasing
the aggregate size. Yang and Jiang analyzed that the reason that smaller aggregate
size generated higher compressive strength might because it enlarged the bond area
between aggregates. However, decreasing aggregate size also resulted in a decreasing
in the permeability.
The gradation of aggregate also affects the properties of pervious concrete.
Crouch et al.9 found that a more uniform gradation deduced to slightly higher
effective void content. Furthermore, the compressive strength was higher at the same
void content in mix that having uniform gradation. The effect of gradation on
compressive strength and permeability was also studied by Wang et al. 10. They
27

showed that a single aggregate size for the pervious concrete had higher permeability
than uniformly graded aggregate mixtures at the same void content.
2.5.2.2 Effect of Fine Aggregate
The experiments carried out by Wang et al.10 indicated that replacement of 7%
of coarse aggregate by sand can improve the compressive strength up to 50%.
However, the void content is deduced by 10%, decreasing the permeability. Although
the permeability decreased in those experiments, it was greater than 140in/hour10.

2.5.3 Effect of Aggregate/Cement Material Ratio
The effect of A/C ratio is illustrated in the research done by Crouch et al.9.
The experimental results showed that increasing the aggregate amount in pervious
concrete results in higher effective void content and lower compressive strength.
Crouch et al.9 explained the reason of this phenomenon: “An increased aggregate
amount also results in a decreased past amount. Hence, there is less paste to fill up the
voids, resulting in higher void contents. Also, less paste is available for aggregate
bonding, which lowers the compressive strength and modulus of elasticity.”

2.5.4 Effect of Water/Cement Ratio
Various W/C ratios have been recommended, normally falling in a range
between 0.22 and 0.45. In the brochure “CIP 38 – pervious concrete”1 published by
NRMCA, a range of 0.35 to 0.45 of W/C ratio is given as a typical ratio for pervious
concrete. However, Wang et al.10 mixed pervious concrete batches with W/C ratios
28

0.22 and 0.27, and suggested using the lower value, if workability could be
maintained. In contrast, in an actual applicaiton published by NRMCA29 W/C ratio up
to 0.55 was used.
W/C should be large enough so that hydration of cementitious materials can
fully develop. Yang and Jiang6 pointed out that the cement bond should provide good
connection between aggregate so that the failure is by splitting of the aggregate, in
which way the mixture most effectively works. However, too much water may
decrease the strength, which is known to be the case in conventional concrete.
Furthermore, excessive water will result in settlement of paste, sealing the bottom of
pervious concrete.

2.5.5 Effect of fly ash
Generally, fly ash is realized to be able to decrease the permeability of
conventional concrete, increase freeze-thaw durability of concrete, and improve the
later-age strength of concrete. The effect of fly ash will be thoroughly discussed in
Chapter 3.

2.5.6 Effect of Compaction Energy
Compaction energy has been shown by several researchers12,13,23,27 to affect
the compressive strength, freeze-thaw durability, and permeability.
Suleiman et al.12 found the significant effect of compaction energy on freezethaw durability and compaction failure mode of pervious concrete based on the
experiments conducted by Schaefer et al.23. The specimens compacted at lower
29

energy sustained less cycles of freeze-thaw (110 cycles) at failure than those (failed at
153 cycles and 196 cycles) compacted at higher energy. Suleiman et al. 23 also found
an interesting phenomenon that samples compacted at regular compaction energy
failed through the aggregate, while samples compacted at lower energy failed through
both aggregate and paste.
Crouch et al.27 studied the effect of compaction energy on permeability by
comparing the experimental results of specimens with the same mixture design while
compacted at six different compaction efforts. By investigating the effective air void
content and the permeability of both in field and laboratory pervious concrete
mixtures, Crouch et al. found that larger compaction effort resulted in less effective
void content of pervious concrete.
To further study the effect of compaction energy, various compaction methods
were used and compared by Rizvi et al.13. The compaction method is determined
from the compaction equipment, compaction cycles, and compaction forces. Widely
used compaction equipment includes standard tamping rod, standard Proctor hammer
in laboratory and compact roller in field.
In the research reported by Rizvi et al.13, five different consolidation
techniques as illustrated in Table 2.2 were used to cast identical 6in x 12in cylinders.
For each consolidation technique, samples were prepared for 7, 14 and 28 day
compressive strength testing, permeability, and air void testing. The results revealed
the optimum compaction technique was a standard Proctor hammer 10times/layer for
2 layers. Samples compacted by this method achieve both relatively high compressive
strength and high permeability. In addition, the cylinders compacted by this method
30

“also achieved the most consistent results with the least variance for compressive
strength and relatively low standard deviations for permeability and air void”13.

Method

Layers

Drops
/Tamping
rod/layer

Voids
(%)

28Days
Compressive
Strength (MPa)

Permeability
(cm/s)

Rod

3

25

18.5

18.3

0.719

Rod

3

15

21.2

21

1.03

Rod
Proctor
Hammer
Proctor
Hammer

3

5

21.8

15.7

1.027

2

10

19.9

17.5

0.584

2

20

17.2

20.7

1.041

Table 2.2. Compaction Method Conducted by Rizvi et al.13

Compared to the lab testing, the field compaction methods have been less
studied. However, Hein and Schindler18, when reviewing the projects on Auburn
University campus, mentioned the different compaction results of using vibrating
roller and hand roller in field. By observing these field projects, he stated that
“vibrating roller appeared to seal the surface and collapse the pores, providing too
great a compactive effort. The hand roller guided by side forms seemed to provide the
smoothest finish.”

2.5.7 Effect of Fibers
The positive effect of fibers has been shown in many studies. Yang and Jiang6
added polymer fibers into the pervious concrete and obtained increased compressive
31

strength. The increase of compressive strength might because the fiber enhanced the
binder6. In addition, the permeability was unaffected, which differed to the effects of
other factors and therefore enhanced the advantage of adding fibers in pervious
concrete.

2.5.8 Effect of Other Factors
Some factors such as specimen size and testing method have also been studied
in a few cases. Although these factors are not critical to determine pervious concrete
properties, they were discussed and may be considered in some situations.
The size of specimen is not usually considered because they are generally
compacted to the standard size defined by national codes. For example, 4in x 8in
cylinders are normally used in the United States for compressive strength test; 6in x
12in cylinders were cast in the University of Waterloo in Canada, while rectangular
cylinders were used in China. To study the impact of diameter on cylinder samples,
McCain and Dewoolkar26 tested the compressive strength on three sets of specimens
with diameter of 3 inches, 4 inches, and 6 inches. For each set, three identical
specimens were tested. The compressive strength drawn from these experiments
ranged between 650psi (4.5MPa) and 1,100psi (7.6MPa). Even for specimens that
were the same size, the compressive strengths were different with 150 to 260psi. The
experimental results showed that the effect of specimen size was unpredictable.
However, the specimens with 4 inches diameters showed higher average compressive
strength compared to the 3 inches and 6 inches diameters specimens. However, the

32

effect of specimen size could not be distinguished from the effect of inconsistent
casting of specimens due to the limited experimental results.
Another factor that affects the compressive strength of pervious concrete is
capping. Capping is sometimes used in compressive strength test to smooth the
surface of pervious concrete specimen, reducing the effect of stress concentration
consequently. The studies on pervious concrete conducted by Kevern33 showed that
the specimens with sulfur capping compound has higher compressive strength than
those without capping.

2.6 Standard Test Methods
Some tests methods that are required for regular concrete may be unnecessary
for pervious concrete. For example, since pervious concrete has low water content
and lower fluidity, the slump test is not informative.
Currently, standard test methods for field permeability, compressive strength,
hardened concrete density and porosity, and flexural strength of pervious concrete are
under development by ASTM C 09/49 34 . Only ASTM C 1688 with title of Fresh
concrete Density (Unit Weight) and Void Content has been published35. Obviously,
the progress of developing standard test methods for pervious concrete is only at
beginning. No standard ASTM test procedure has been suggested to measure the
entrained air content for pervious concrete. In fact, before the finalization of
testing/mixing methods for pervious concrete, people are using those designed for
conventional concrete, even those methods may not be appropriate in many situations.

33

2.7 Pervious Concrete Design
This section introduces pervious concrete mix design, pervious concrete
pavement structure and hydraulic design. The mix design of pervious concrete is
concerned with the properties of pervious concrete used in the pavement; while the
pervious concrete pavement design is the process of designing the whole system of
pavement including the pavement surface and the subgrade layer.

2.7.1 Pervious Concrete Mix Design
Pervious concrete mix design should generate batches that satisfy compressive
strength and permeability requirements. Typical mix designs of pervious concrete
have been recommended by different agencies such as National Ready Mixed
concrete Association, the Southern California Ready Mix concrete Association, and
the Euclid Chemical Company. The recommended mix designs are shown in Table
2.3, Table 2.4, and Table 2.5. The examples of mix design in laboratory experiments
and in field projects have been done and are listed in Appendix I.

34

Material

Amount

(pcy)
Cementitious Materials

450 – 700 lbs

Aggregate

2000 – 2500 lbs

W/C by Mass

0.27 – 0.34

A/C by Mass

4 – 4.5 : 1

Table 2.3. Recommended Typical Mix Design by National Ready Mixed Concrete
Association36

Material

Amount (pcy)

Compacted Voids

≥ 10%

Cement

≥580 lbs

ASTM C-618 fly ash

50 – 116 lbs

Total Cementitious Materials

630 – 696 lbs
27 ft3

Aggregate

Table 2.4. Recommended Typical Mix Design by the Southern California Ready Mix
Concrete Association (adapted from 1)

Material

Amount (pcy)

Cement

600 lbs

Coarse Aggregate 3/8 Limestone

2600 lbs

Water

160 lbs

W/C by Mass

0.27

Table 2.5. Recommended Typical Mix Design by the Euclid Chemical Company37

35

As shown, there is no single accepted mix design for pervious concrete. Since
less water is used than typical for conventional concrete, pervious concrete appears
drier and more sensitive to the actual water content. Water reducer and water retarder
are used in most cases. In addition, the amount of water and other materials are varied
with the mixing condition and may need to be adjusted during mixing process. Hence,
the mixing of pervious concrete should be done by a crew who has been trained in a
certification program.

2.7.2 Pervious Concrete Pavement Hydraulic Design
The purpose of hydraulic design is to provide a pavement system in which
water can easily pass through the top layer, be temporarily stored in the subgrade
layer and freely enter a shallow groundwater.
North Carolina Department of Environment and Natural Resources
(NCDENR) 38 introduced process of hydraulic design for permeable pavement as
illustrated below:
(1) Select Design Storm
(2) Determine Water Storage Capacity of Pavement
(3) Select Exfiltration Time
(4) Calculate Drawdown (Exfiltration) Time
(5) Compare Actual Drawndown with Design Exfiltration
Following this process, designer can calculate the desirable pavement open
space, which can produce the required drainage at a certain rainfall rate. The
pavement is then designed to have this open space.
36

In addition, Malcolm et al.39 developed a program to do the hydraulic design
based on the pervious concrete hydrological analysis program. Input parameters of
the program contains trial thickness of pervious concrete and gravel base, porosity of
pervious concrete and gravel base, local rainfall information, and adjacent areas
which will drain onto pervious concrete. After analyzing the input parameters, the
software can generate a chart to model the flowing situation of rainfall with elapsed
time. Hence, a satisfactory thickness of the pavement and subgrade layers can be
determined by examining the flowing situation.

2.7.3 Pervious Concrete Pavement Structural Design
NCDENR also developed a structural design worksheet for permeable
pavements40. According to the worksheet, the structural design of pervious concrete
includes four elements: total traffic, in-situ soil strength, environmental elements, and
actual layer design. The primary purpose of the structural design is to examine and
finalize the thickness of subgrade layer. The top layer of pavement is set to the
pervious concrete block, which is usually 6 inches or more. The thickness of pervious
concrete pavement is greater than those of regular concrete that is 4 inches in
normal11 because pervious concrete has lower compressive strength than regular
concrete.
Before beginning the structural design, the thickness of each layer has been
determined from the hydraulic design. Only the thickness of subgrade layer will be
checked in the structural design to determine whether or not the pavement is strong
enough. A formula is given to determine a calculated Structural Number (SNcalc),
37

which will be compared to the Structural Number (SN) determined from a nomograph
design chart40 shown in Figure 2.4. Figure 2.4 gives an example of how to obtain a
SN: 1) from soil support value of 7 and total equivalent 18-kip single-axle load
applications of 1500psi, the structural number of 2.3 is obtained by extending a line to
the structure number scale; 2) connects the structure number of 2.3 and regional
factor of 4.0, and extends the line to the scale of weighted structure number, SN = 3.2
is obtained. If calculated SNcalc is greater than the SN, the thickness of subgrade is
satisfied. Otherwise, the thickness needs to be increased. Generally, 6 inches to 12
inches layer of permeable subbase is used in pervious concrete pavement.

Figure 2.4. Nomograph to Determine Structural Number (Pavement Strength) 40

38

The permeable subgrade might be composed of either 1 inch maximum-size
aggregate, or a natural subgrade soil that is predominantly sandy with moderate
amounts of silt, clay, and poorly-graded soil38. However, the top 6 inches of the
subgrade is usually made of #4 granular or gravelly materials with no more than a
moderate amount (10%) of silt or clay41. The design of subbase is primarily based on
its stormwater storage ability, and the modulus of subgrade reaction (k) is another
design criterion. NCDENR suggests a suitable range 150-175 lb/in3 for k value, which
can be obtained using theoretical relationship between k values from plate-bearing
tests (ASTM D 1196 and AASHTO T 222), or estimated from the elastic modulus of
subgrade soil 38.
8

Funding Universe, “George Wimpey plc.”
<http://www.fundinguniverse.com/company-histories/George-Wimpey-plcCompany-History.html> (April 19, 2009).
9

Crouch, L. K., Pitt, J. and Hewitt, R. (2007). “Aggregate effects on pervious
Portland cement concrete static modulus of elasticity.” Journal of Materials in
Civil Engineering, ASCE.
10
Wang, K., Schaefer, V. R., Kevern, J. T., and Suleiman, M. T. (2006).
“Development of mix proportion for functional and durable pervious concrete.”
submitted to NRMCA concrete technology forum: focus on pervious concrete.
11

Wanielista, M., and Chopra, M. (2007). “Performance assessment of Portland
cement pervious pavement.” Final Report FDOT project BD521-02,
<http://www.dot.state.fl.us/researchcenter/Completed_Proj/Summary_RD/FDOT_BD521_02_rpt4.pdf> (Dec. 25,
2009).
12

Suleiman, M. T., Kevern, J., Schaefer, V. R., and Wang, K., “Effect of
compaction energy on pervious concrete properties.” Iowa State University,
<http://www.rmcfoundation.org/images/PCRC%20Files/Construction%20Techniques/Effect%20of
%20Compaction%20Energy%20on%20Pervious%20Concrete%20Properties.pdf
> (Feb. 04, 2010).
39

13

Rizvi, R., Tighe, S., Henderson, V., and Norris, J. (2009). “Laboratory sample
preparation techniques for Pervious Concrete.” TRB Annual Meeting. Report No.
09-1962, p. 16.
14

“Rocky Mountain Construction.” Brochure of Associated Construction
Publication, <www.acppubs.com> (Dec. 10, 2007).
15

Houston Advanced Research Center (HARC) (2004).
<http://files.harc.edu/Projects/CoolHouston/CoolHoustonPlan.pdf> (June, 2010).
16

Kim, H. K., and Lee, H. K. (2010) “Acoustic absorption modeling of porous
concrete considering the gradation and shape of aggregates and void content.”
Journal of Sound and Vibration, 329(7), 866-879,
<http://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6WM34XKXRPV-115&_cdi=6923&_user=3366836&_pii=S0022460X09008086&_orig=search&_co
verDate=03%2F29%2F2010&_sk=996709992&view=c&wchp=dGLbVzbzSkzS&md5=8c8d1d4c1df436253154fa16f925993d&ie=/sdarticle.pdf> (Mar. 31,
2010).
17

ASTM C 666 (2009). “Standard test method for resistance of concrete to rapid
freezing and thawing.” ASTM international, DOI: 10.1520/C0666_C0666M-03,
<http://www.astm.org/Standards/C666.htm> (June 30, 2010).
18

Hein, M. F, and Schindler, A. K. (2007). “Learning pervious: concrete
collaboration on a university campus.” <http://www.rmcfoundation.org/images/PCRC%20Files/Applications%20&%20Case%20Studies/
Learning%20Pervious%20%20Concrete%20Collaboration%20between%20Workers%20and%20Students%
20on%20a%20University%20Campus.pdf> (Feb. 9, 2010).
19

Dietz, M. E. (2007). “Low impact development practices: a review of current
research and recommendations for future directions.” Water Air Soil Pollutant, v.
186, p. 351-363.
20

ASTM C 33. (2008). “Standard specification for concrete aggregates.” ASTM
international, DOI: 10.1520/C0033_C0033M-08,
<http://www.astm.org/Standards/C33.htm> (June 30, 2010).
21

ASTM C 494. “Standard specification for chemical admixtures for
concrete.” ASTM international, DOI: 1520/C0494_C0494M-10,
<http://www.astm.org/Standards/C494.htm> (June 30, 2010).

40

22

ASTM C 260 (2006). “Standard specification for air-engineering admixtures
for concrete.” ASTM international, DOI: 10.1520/C0260-06,
<http://www.astm.org/Standards/C260.htm> (June 30, 2010).
23

Schaefer, V. R., Wang, K., Suleiman, M. T., and Kevern, J. T. (2006). “Mix
design development for pervious concrete in cold weather climates, final report.”
National Concrete Pavement Technology Center, Iowa State University.
24

Haselbach, L. M., Valavala, S., and Montes, F. (2006). “Permeability
predictions for sand-clogged Portland cement pervious concrete pavement
systems.” Journal of Environmental Management, v. 81, p. 42-49.
25

Montes, F., and Haselbach, L. M.(2006). “Measuring hydraulic conductivity in
pervious concrete.” Environmental Engineering Science, 23(6).
26

McCain, G. N., and Dewoolkar, M. M. (2009). “Strength and permeability
characteristics of porous concrete pavements.” TRB 88th Annual Meeting
Compendium of Papers (CD-ROM), Transportation Research Board 88TH
Annual Meeting.
27

Crouch, L. K., Smith, N., Walker, A. C., Dunn, T. R., and Sparkman, A. (2006).
“Determining pervious PCC permeability with a simple triaxial flexible-wall
constant head permeameter.” TRB 2006 Annual Meeting (CD-ROM),
<http://www.rmcfoundation.org/images/PCRC%20Files/Specifications%20&%20Test%20Method
s/Determining%20Pervious%20PCC%20Permeability%20with%20a%20Simple
%20Triaxial%20Flexible-Wall%20Constant%20Head%20Permeameter.pdf>
(Dec. 25, 2009).
28

ASTM C 39 (2009). “Standard test method for compressive strength of
cylindrical concrete specimens.” ASTM international, DOI:
10.1520/C0039_C0039M-09A, <http://www.astm.org/Standards/C39.htm> (June
30, 2010).
29

North Carolina Department of Environment and Natural Resources (2004).
“Freeze thaw resistance of pervious concrete.” brochure of National Ready Mixed
Concrete Association, <http://www.nrmca.org/greenconcrete/nrmca%20%20freeze%20thaw%20resistance%20of%20pervious%20concrete.pdf> (Feb. 08,
2010).
30

Wingerter, R., Paine, J. (1989). “Field performance investigation Portland
cement pervious pavement.” Florida Concrete and Products Association.

41

31

Meininger, R. C. (1998). “No-fines pervious concrete for paving.” Concrete
International, 10(8), 20-27.
32

Mulligan, A. M. (2005). “Attainable compressive strength of pervious concrete
paving system.” A thesis submitted in partial fulfillment of the requirements for
the degree of Master of Science, Department of Civil Engineering, University of
Central Florida, <http://www.rmcfoundation.org/images/PCRC%20Files/Structural%20Design%20&%20Propertie
s/Attainable%20Compressive%20Strength%20of%20Pervious%20Concrete%20P
aving%20Systems.pdf> (June 14, 2010).
33

Kevern, J. T. (2006). “Mix design development for Portland cement pervious
concrete in cold weather climates.” A thesis submitted to the graduate faculty in
partial fulfillment of the requirements for the degree of Master of Science, Iowa
State University.
34

Haselbach, L. (2009). “Standard test methods for pervious pavements.”
<http://www.psparchives.com/publications/our_work/stormwater/lid/2009_Local
_Assitance/005_Appendices/Standard_Test_Methods_for_Pervious_Pavement.pd
f> (June 16, 2010).
35

ASTM C 1688 (2009). “Fresh concrete density (unit weight) and void content.”
ASTM international, <http://www.astm.org/Standards/C1688.htm> (June 30,
2010).
36

North Carolina Department of Environment and Natural Resources (NRMCA).
<http://www.perviouspavement.org/structural%20design.htm> (May 19, 2010).
37

Euclid Chemical Company (2009). “Pervious concrete.” Brochure of Euclid
Chemical Company,
<http://www.euclidchemical.com/fileshare/elit/B38_Pervious_Concrete_Brochure
_06_09.pdf> (June 14, 2010).
38

North Carolina Department of Environment and Natural Resources (NCDENR)
(1997). <http://www.bae.ncsu.edu/cont_ed/bmp/readings/hydrdes.htm> (April 29,
2010).
39

Malcolm, H. R., Leming, M. L., and Nunez, R. A. (2006). North Carolina State
University, Raleigh, North Carolina, North Carolina Department of Environment
and Natural Resources NCRMCA.
40

North Carolina Department of Environment and Natural Resources (NCDENR).
(1997),
42

<http://www.rmcfoundation.org/images/PCRC%20Files/Structural%20Design%20&%20Propertie
s/Structual%20Design%201.pdf> (April 29, 2010).
41

ACI Committee 522. (2006). “Pervious concrete.” ACI 522R-06, American
Concrete Institute.

43

CHAPTER 3
LITERATURE REVIEW OF FLY ASH

3.1 Introduction of Coal Combustion Products (CCPs)
According to the U. S. Environmental Protection Agency, Coal Combustion
Products (CCPs) “are the byproducts generated from burning coal in coal-fired power
plants. These byproducts include fly ash, bottom ash, boiler slag, and flue gas
desulfurization gypsum”42. The CCPs are used in many fields such as engineering
construction, agriculture, and waste stabilization. The American Coal Ash
Association (ACAA) released statistic of the multiple applications of CCPs in 2008 in
the United States, as shown in Figure 3.1. As shown, CCPs are mainly used in
concrete products, structure fills, and wallboard 43.

44

Figure 3.1. Uses of Coal Combustion Products in 2008 (AACA adapted from U. S
Environmental Protection Agency (EPA)43)

Based on statistics from the committee on Promoting & Advancing Coal
Combustion Products (ACAA) 44, the utilization of CCPs from 1966 to 2007 increased
from 20% to 40% as shown in Figure 3.2. The figure illustrates that the amount of
CCPs produced dropped in 2003 and has remained steady since 2007. According to
the EPA, the utilization rate of CCPs was 36.8% in 2008, and is aimed to increase to
45% in 201145.

45

Figure 3.2. 1966-2007 CCP Beneficial Use vs. Production (AACA44)

CCPs are used in various areas depending on their properties. Typically,
bottom ash is used as aggregate in concrete and in cold mixed asphalt, and is also
used as a structural fill for embankments and cement-stabilized bases for highway
construction. Flue Gas Desulfurization (FGD) material is used for wallboard
production, structural fill, cement, concrete, and grout. Boiler slag is used for roofing
granules, blasting grit, asphalt concreted aggregate, structural fill, granular base
material for pavement construction, stabilized base aggregate. Fly ash can be used in
several areas: replacing Portland cement in concrete and grout; filling embankments;
and being added in aggregate for highway subgrades of road base 46 . Figure 3.3
presents the percentage of CCPs used in 2003 in the United States. As illustrated,
46

except for boiler slag, only 30% to 50% of each type of CCPs is used. Figure 3.3 also
indicates that although only around 40% of generated fly ash was used, the total
weight of utilized fly ash accounted more than half of the total utilized CCPs in 2004.

Figure 3.3. Coal Combustion Products Generation and Use (Short Tons) (AACA
adapted from EPA46)

3.2 Introduction of Fly Ash
Fly Ash is a fine residue powder byproduct from burning pulverized coal in
electric power generating plants. It is the finest and is the most broadly used material
of all the byproducts. It is called “fly” ash because it is transported from the
combustion chamber by exhaust gases47.

47

3.2.1 Properties of Fly Ash
The physical and chemical properties of fly ash have been studied and
analyzed by many researchers48. The study of its physical properties origins back to
1930s when the term of fly ash was generated49. According to EPA, fly ash consists
of fine, powdery particles that are predominantly spherical in shape, either solid or
hollow, and mostly glassy (amorphous) in nature, having similar physical
characteristic with silt 50. Compared to its physical properties, its chemical properties
are more influenced by the type of burned coal and the techniques used for handling
and storage51.

3.2.2 Class C and Class F Fly Ash
Class C and Class F fly ash are classified according to the ASTM C 61852.
Class C contains more lime than is present in class F fly ash. Class C fly ash has both
pozzolanic and cementitious properties, and is mostly used in the situations where
high early strength is important such as prestressed applications. Class F fly ash is
considered an ideal pozzolanic material in mass concrete and high strength mixes,
and is recommended to be used in concrete exposed to ground water53.

3.2.3 Utilization of Fly Ash in Concrete
As shown in Figure 3.4, the greatest utilization of fly ash in 2003 according to
the American Coal Ash Association was in concrete and grout products. The
beneficial results of adding fly ash to concrete include: (1) Increased concrete
durability and strength of concrete: the lime from cement hydration reacts with fly
48

ash, increasing the long-term strength of concrete. Compared to plain cement
concrete, fly ash concrete gains higher strength after 28 days; (2) Improved concrete
workability: fly ash produces more cementitious paste, increasing the lubrication
between aggregate and flowability of concrete; the spherical shape of fly ash and its
dispersive ability provide effects similar to those of water-reducing agents; the usage
of fly ash also reduces the amount of sand needed in the mix to produce workability.
Because sand has a greater specific surface area than larger aggregates and therefore
requires more paste, reducing the sand means the paste would efficiently coat the
surface area of aggregates54.

Figure 3.4. Top Uses of Coal Fly Ash 2003 (AACA adapted from46)

49

The usage of ash in building application can be traced back to thousands of
years ago in ancient Rome, when people used volcanic ash in their construction to
strengthen the structure. Examples of the buildings are the Roman Pantheon and the
Coliseum. The fly ash has similar function as the volcanic ash, and this function has
been realized for decades. In 1930s, fly ash was first used as mineral filler in asphalt
mixes; in 1942, fly ash concrete was used to repair a tunnel spillway at the Hoover
Dam49. Fly ash has now been used as an ingredient in concrete for more than 60 years.
In January of 1974, the Federal Highway Administration (FHWA) encouraged
the use of fly ash in concrete pavement with the Notice N 5080.4, urging states to
allow partial substitution of fly ash for cement whenever feasible 55. The FHWA also
indicated that “the replacement of cement with fly ash of the order of 10% to 25% can
be made giving equal or better concrete strength and durability.” In January 1983, the
EPA published federal procurement guidelines for cement and concrete containing fly
ash, encouraging the utilization of fly ash55. Currently, fly ash is used to replace 565% of the Portland cement 2. Because the manufacture of cement is highly energy
intensive, using fly ash as an element replacement of in concrete can reduce
significantly the environmental cost of concrete.

3.2.4 Environmental Benefits of Fly Ash Use
Using fly ash in place of natural materials can yield benefits to the
environment, economic, and product performance improvements by saving source
materials, reducing energy consumption and greenhouse gas emissions. The LEED
assigns up to 5 credits to the combined usage of fly ash and recycled material56. Fly
50

ash also makes economic benefit because it is often less costly than the materials that
it replaces, such as sand, gravel, or gypsum.

3.3 Effect of Fly Ash on Concrete
The positive effects of adding fly ash into concrete have been mentioned
before. Most of the effects were drawn from experiment and field projects. This
section will discuss the influence of fly ash on concrete in detail by referencing the
prior studies.

3.3.1 Thermal Cracking
ISG Headwaters Resources Inc. published a brochure and stated that the
existence of fly ash could decrease the rapid heat and consequently reduce the risk of
thermal cracking 57 . Many applications indicate that rapid heat gain of cement
increases the chances of thermal cracking, leading to reduce concrete strength and
durability57. With replacement of fly ash, the chance of thermal cracking will be
decreased because only 15% to 35% as much heat as compared to cement at early
ages are generated by fly ash.

3.3.2 Compressive Strength
Fly Ash can increase the long-term compressive strength of concrete. Figure
3.5 compares the strength of fly ash concrete with plain cement concrete. In this
graph, the plain cement concrete strength increase is slower than fly ash concrete
strength increase. In both types of concrete, strength increase slows after the initial 7
51

day curing period. The plain cement concrete has higher strength than fly ash
concrete before 28 days curing period and lower compressive strength after then.

Figure 3.5. Comparison between Ash Concrete Compressive Strength and Plain
Cement Concrete Compressive Strength57.

The increased compressive strength of fly ash concrete compared with plain
cement concrete can be explained by examining the chemical reaction taking place in
the concrete. Typically, Portland cement and water react to produce durable binder
(Calcium Silicate Hydrate (CSH)) and a nondurable binder (free lime). In fly ash
concrete, the free lime continues to react with fly ash to produce more CSH.
According to the Headwater Resources report57, approximately ¼ pounds of free lime
will be produced with 1 pound of cement. This indicates that large amount of free
lime exists in plain cement concrete and available to react with fly ash to produce
more CSH. Hence, the utilization of fly ash can save lots of cement while maintaining
52

the compressive strength of concrete because they generate the same binder with
cement does. Fly ash can also reduce W/C ratio with typical 2% to 10% water
reduction because of its spherical shape of the individual particles57. The compressive
strength might be improved because of the decrease of W/C ratio.

3.3.3 Durability
According to the research by Khunthongkeaw and Tangtermsirikul58, fly ash
can promote the carbonation process and consequently improve the long-term
serviceability of concrete. The CO2 existing in the atmosphere can react with the
calcium hydroxide in concrete and reduce the alkalinity of the pore solution. This
carbonation process will cause the erosion of steel. Khunthongkeaw and
Tangtermsirikul stated that fly ash can increase the rate of carbonation, and speed up
the reduction of alkalinity so that the alkalinity reduction is done in short period time.
In turn, the long-term serviceability could be improved58.
According to the Headwater Resources bulletin No.959, Fly ash can help to
increase the freeze-thaw resistance ability of concrete. By reacting with free lime, the
fly ash generates more durable binder materials by reacting with free lime. This not
only increases the density of concrete, but also decreases the amount of calcium
hydroxide which is generated from free lime. Consequently, the minute voids and the
potential voids caused by the leaching of calcium hydroxide are decreased. Fly ash
spherical shape may reduce the bleed channel and void space, reducing the possibility
of water accumulating59.

53

Fly ash increases the durability of concrete. According to the Headwater
Resources bulletin No.2260, practical testing indicated that the DOT’s concrete for
bridge superstructures and decks containing 20% fly ash would likely provide a 75year service life in a marine environment. Because of its advantages in harsh
environment, the Utah and Nevada DOTs mandated 20% fly ash usage in all concrete
work60.

3.3.4 Permeability
One advantage of decreased permeability is to reduce the rate of ingress of
water, corrosive chemicals and oxygen, thus protecting steel reinforcement from
corrosion. As discussed before, when more CSH is formed the bond between
aggregates is enhanced. At the same time the capillaries in concrete are blocked off
during this process, resulting in decreasing permeability. The characteristic that fly
ash decreases the permeability of concrete was studied by Elfert (adapted from
Headwater Resources bulletin No.661 ), and a Cementing Materials in Concrete vs.
Permeability Rate chart shown as Figure 3.6 was released. It is clear from this work
that a 30% fly ash replacement of cement dramatically decreased the permeability of
concrete. The amount of decrease varied with the amount of cement in concrete mix.
The less cement that concrete had, the more the permeability was decreased.

54

Figure 3.6. Effect of Fly Ash on Permeability of Concrete (adapted from61)

3.3.5 Sulfate Attack
Fly Ash can increase sulfate resistance and reduces alkali-silica reactivity, and
Class F fly ash is more productive than Class C fly ash on this effect 62 . The
mechanism of sulfate attack happens in two ways: (1) sulfate reacts with calcium
hydroxide (CaOH) and generates gypsum with the volume increased during the
process; (2) sulfate reacts with aluminates in concrete and generate expansive
compound. Both processes are combined with the expansion of concrete, which is the
source of concrete damage. When fly ash is used, it will tie up free lime, thus reduce
55

calcium hydroxide (CaOH). In turn, the chemical reaction in concrete can be reduced
and large expansion and damage can be decreased.

3.4 Fly Ash in Pervious Concrete
Based on the publication of Headwaters Resources63, up to 20% percentage of
Portland cement in pervious concrete can be replaced by fly ash. The usage of fly ash
can help to improve the workability of the low slump mix so as to benefit the placing
and mixing process. The fly ash used in pervious concrete should satisfy the
requirement of ASTM C 61852 as specified in ACI 522R-0641.

3.5 Summary
Overall, the usage of fly ash in plain cement concrete has been shown to
improve the long-term strength, freeze-thaw durability, and decrease durability of
plain cement concrete. However, the study of fly ash effects on pervious concrete was
limited. In the following chapters, portions of cement in pervious concrete will be
taken place by fly ash. The unit weight, compressive strength and permeability of
mixes with various fly ash content will be measured and compared to study the effect
of fly ash on pervious concrete.
42

U. S Environmental Protection Agency (EPA). (2010). “What are coal
combustion products?”
<http://www.epa.gov/epawaste/partnerships/c2p2/index.htm> (Mar. 01, 2009).
43

EPA. (2010). “CCP applications.”
<http://www.epa.gov/epawaste/partnerships/c2p2/use/index.htm> (Mar 01, 2009).
44

ACAA (2009). “1996-2007 CCP Beneficial Use v. Production.” American
Coal Ash Association, < http://www.acaa-usa.org/associations/8003/files/
Revised_1966_2007_CCP_Prod_v_Use_Chart.pdf >(July 6, 2009).
56

45

EPA “C2P2 results.”
<http://www.epa.gov/epawaste/partnerships/c2p2/results.htm> (June 30, 2010).
46

EPA. (2005). “Using coal ash in highway construction: a guide to benefits and
impacts.” Report no. EPA-530-K-05-002.
<http://www.epa.gov/osw/partnerships/c2p2/pubs/greenbk508.pdf > (June 30,
2010).
47

Coal Ash Research Committee. (2010). “What is coal ash?” University of North
Dakota, < http://www.undeerc.org/carrc/html/WhatisCoalAsh.html> (June 30,
2010).
48

Hassett, D. J., and Heebink, L. V. (2001). “JV task 13 – environmental
evaluation for utilization of ash in soil stabilization.” 2001-EERC-08-06, Final
report prepared for AAD Document Controal, National Energy Technology
Laboratory, U.S Department of Energy. Prepared by Energy & Environmental
Research Center, University of North Dakota
<http://www.undeerc.org/carrc/Assets/SoilStabilization.pdf> (June, 2010).
49

Coal Ash Research Committee. (2010). “Historical timeline.” University of
North Dakota,<http://www.undeerc.org/carrc/html/HistoricalTimeline.html> (June
30, 2010).
50

EPA. (2010). “Fly ash.”
<http://www.epa.gov/osw/conserve/rrr/imr/ccps/flyash.htm>
(June 30, 2010).
51

EPA (2008). “Identification of nonhazardous secondary materials that are solid
waste coal combustion residuals - coal fly ash, bottom ash, and boiler slag,
<http://www.epa.gov/epawaste/nonhaz/pdfs/ccpash.pdf> (Mar. 01, 2009).
52

ASTM C 618-08a. (2009). “Standard specification for coal fly ash and raw or
calcined natural pozzolan for use in concrete.” ASTM international, DOI: 10.
1520/C0618-08 <http://www.astm.org/Standards/C618.htm> (June 30, 2010).
53

Headwaters Resources. (2005). “Fly ash – types and benefits.” Bulletin No. 1, 1
page, <http://www.flyash.com/data/upimages/press/TB.1%20Fly%20Ash%20%20Types%20&%20Benefits.pdf> (June 30, 2010).
54

“Fly ash for concrete brochure,” ISG Resources, Headwaters Resources,
<http://www.flyash.com/resourcelibrary.asp?category=Fly+Ash+Basics&Submit
=search> (Dec. 31, 2009).
55

FHWA. (2010). “Fly ash facts for highway engineers.”
57

<http://www.fhwa.dot.gov/pavement/recycling/fapref.cfm> (June 30, 2010).
56

Headwaters Resources. (2005). “Fly ash and concrete in LEED® - NC version
2.2”, Bulletin No. 28, 1 page,
<http://www.flyash.com/data/upimages/press/LEED%20ver%202.2.pdf> (June
30, 2010).
57

Headwaters Resources. (2005). “Fly ash for concrete.”
<http://www.flyash.com/data/upimages/press/HWR_brochure_flyash.pdf> (June
30, 2010).
58

Khunthongkeaw, J., and Tangtermsirikul, S. (2005) “Model for simulating
carbonation of fly ash concrete” Journal of Materials in Civil Engineering, ASCE,
17(5), 570-578.
59

Headwaters Resources. (2005). “Fly ash increase resistance to freezing and
thawing.” Bulletin No. 9, 1 page.
60

Headwaters Resources. (2005). “High volume fly ash for concrete paving.”
Bulletin No. 22, 1 page.
61

Headwaters Resources. (2005). “Fly ash decreases the permeability of
concrete.” Bulletin No. 6, 1 page.
62

Headwaters Resources. (2005). “Fly ash increases resistance to sulfate attack.”
Bulletin No. 7, 1 page.
63

Headwaters Resources. (2005). “Fly ash decreases the permeability of
concrete.” Bulletin No. 29, 1 page.

58

CHAPTER 4
LABORATORY MIX AND TEST

4.1 Introduction
Laboratory preparation and tests will be introduced in this section. First of all,
the type and amount of each material were selected. The selection of various material
and values of W/C ratio, A/C ratio was based on the literature reviews presented in
Chapter 2 and Chapter 3. Secondly, the unit weight, void content, compressive
strength, permeability of pervious concrete were measured according to the
appropriate ASTM standards. Some problems encountered during the process of
concrete mixing and laboratory testing will also be discussed.

4.2 Mix Preparation
Since the purpose of this research was to identify mixes with high
compressive strengths, optimum mix designs obtained by previous studies were taken
as reference in this research.

4.2.1 Mix Materials
This section introduces the properties of materials used in this research. All
materials were obtained from local sources.

59

4.2.1.1 Coarse Aggregate
After reviewing the literature and investigating actual projects, #8 river gravel
was used in this research. This material was provided by the Olen Corp. One of the
reasons for choosing this gravel was its wide availability. As discussed in Chapter 2,
the size and gradation of coarse aggregate is one of the factors that affect the
properties of pervious concrete. Based on the study by Schaefer et al.23, the optimum
coarse aggregate type gradation was the single sized river gravel that passed through
3/8 inches and was retained in sieve size No. 4. However, this was less practical in
field projects. Normally, the material obtained from aggregate supplies was gradated
instead of in single size. Hence, #8 river gravel was chosen because it had closest
gradation to the optimum one. In addition, this type of coarse aggregate was also
widely used by Buckeye Ready-Mix LLC., and Anderson Concrete Corp, which both
produce pervious concrete for field projects. The physical properties were provided
by the Olen Corp. and are shown in Table 4.1. The grain size distribution is shown in
tabular form in Table 4.2 and depicted in Figure 4.1. The distribution of coarse
aggregate follows ASTM20.

60

Soundness Loss

5.6

Specific Gravity

2.517

Specific Gravity SSD

2.585

Absorption

2.72

Unit Weight (pcf)

103.0

Clay Lumps & Friable Particles

0.0%

Light Weight Chert

0.0%

LA Abrasion

22.4

Table 4.1. Physical Properties of #8 River Gravel (Olen Corp.)

Sieve Identification
Sieve Size (in)
Percent Finer by
Weight

1/2
inches
0.5

3/8
inches
0.375

#4
0.187

#8
0.0929

#16
0.0465

#50
0.0118

100

92

17

2

1

0.5

Table 4.2. Coarse Aggregate Distribution (Olen Corp.)

#8 River Gravel

Percentage Finer by Weight (%)

100

80

60

40

20

0
1

0.1

0.01

Sieve Size (in)

Figure 4.1. Grain Distribution Curve of Size Number 8 River Gravel (Olen Corp.)
61

4.2.1.2 Fine Aggregate
The sand used in this research was QUIKRETE® all purpose sand No. 1152,
which met ASTM C 33 specifications20, 64.
4.2.1.3 Cement
Type I cement from St. Marys Inc. was used in this study. The
properties of cement were obtained from the company website and are shown in
Table 4.3. The properties met the requirements specified in ASTM standard C15065
(provided by St. Marys Inc., personal communication).

62

Loss on Ignition

2.9%

SiO2

18.9%

Fe2O3

2.16%

Al2O3

4.8%

CaO

61.4%

Free CaO

1.3%

MgO

2.5%

SO3

3.81%

K2O

1.12%

Na2O

0.24%

TiO2

0.3%

Insoluble Residue

0.52%

Total Alkali as Na2O

0.98%

CO2

1.3%

Limestone

3.1%

CaCO3 in Limestone

97%

Table 4.3. Chemical Properties of St. Marys Type I Cement (St. Marys, Inc.)

4.2.1.4 Fly Ash
The fly ash used in experiments was Class F Cardinal fly ash came from
American Electric Power Co. Inc. The specific gravity of fly ash was 2.1 (Modi,
personal communication). The chemical properties is physical properties of fly ash is
listed in Table 4.4.

63

Particle size (mm)

0.001-0.1

Compressibility (%)

1.8

Dry Density (lb/ft3)

40-90
10-6-10-1

Permeability
Shear strngth cohision (psi)

0-170

Angle of internal friction

24-45

Table 4.4. Physical Properties of fly ash66

4.2.1.5 Admixture
Admixtures including HRWR, MRWR, water retarder, viscosity modifying
admixtures, and fibers were provided by the Anderson Concrete Corp. and the Euclid
Chemical Company37. High efficiency polycarboxylate based HRWR PLASTOL
6200 EXT and MRWR EUCON MRX were used to maintain the low W/C ratio and
increase the workability. The addition of viscosity modifying admixture made
pervious concrete more manageable and improved the adhesion between cement and
aggregate, maintaining the air void structure integrity. Eucon W. O. water retarder
helped to prolong the hydration of cement. The typical dosages are indicated in Table
4.5. The dosage of water-reducer was based on total weight of cementitious material.

64

Admixtures

Name

Typical dosage

Polypropylene Micro-Fiber

Fiberstrand 100

High-Range Water Reduer

PLASTOL 6200 EXT

3-12fl.oz/100lb

Water Retarder

EUCON W.O

4-16fl.oz/100lb

Mid-Range Water Reducer

EUCON MRX

3-12fl.oz/100lb

Viscocity Modifying Admixture

Visctrol

1lb/yd3

1-20fl.oz/yd3

Table 4.5. Admixtures from Euclid Chemical Company37

4.2.2 Mix Design
A total of six batches of pervious concrete as indicated in Table 4.6 were
studied in this research. The mix design followed the phase-volume design procedure,
as introduced in ACI 211.167,68 . The A/C ratio and W/C ratio were calculated by
weight. The volume of each material was obtained from the division of weight and
density. The design volume of each batch was dependent on the volume of materials
and design void content. The amount of coarse aggregate was initialized as
2,400lb/yd3 to 2,700lb/yd3. This was used to calculate cement amount and void
content according to the design A/C and W/C ratios.

65

Mix
No.
#1
#2
#3**
#4
#5
#6

Cement
(lb/yd3)
430
325
484
334
620
381

Mix
No.
#1
#2
#3**
#4
#5
#6

Total
Aggreg
ates
(lb/yd3)
1965
2137
2520
2298
2698
2550

Coarse
Aggregate
(lb/yd3)
1862
2025
2520
2184
2563
2428

Sand
(lb/yd3)
103
112
0
114
135
122

Total
Cementitious
Materials
(lb/yd3)
430
464
530
477
632
561

Class F
Fly
Ash
(lb/yd3)
0
139
46
143
12
180

HRWR/
MRWR
(oz/cwt)
5*
5*
6
8
8
8

Sand/Total
Aggregate
(%)
5%
5%
0%
5%
5%
5%

Water
Retarder
(oz/cwt)
2*
2*
12
8
8
8

Class F Fly
Ash/Total
Cementitious
Material (%)
0%
30%
9%
30%
2%
32%

W/C
0.27
0.22
0.37
0.32
0.34
0.34

Visctrol
(oz/cwt)
2*
3*
1
10
10
10

Fiber
(oz/c
wt)
---1
1
1

A/C
4.6
4.6
4.8
4.8
4.3
4.5

Table 4.6. Pervious Concrete Mix Design
Note: * from Anderson Concrete Corp.
** from Buckeye Ready Mix Corp.

Mix ID as listed in Table 4.7 was assigned to each batch of mix so that the
mixing proportions could be easily told by the identification number.

66

Mix No.
#1
#2
#3
#4
#5
#6

Mix ID
AC46-FA00-WC27-5SD
AC46-FA30-WC22-5SD
AC48-FA09-WC37-0SD
AC48-FA30-WC32-5SD
AC43-FA02-WC34-5SD
AC45-FA32-WC34-5SD

Table 4.7. Mix No. Corresponding to Mix ID.
Example: AC48-FA32-WC32-5SD stands for the batch of mix with aggregate/cement
ratio 4.8; fly ash content 32%, water/cementitious material ratio is 0.32, and sand
content 5% by weight of total aggregates.

A program was developed to do pervious concrete mix design based on the
phase-volume design procedure, and is illustrated in Figure 4.2. The input data
include total cementitious materials, percentage of fly ash, A/C ratio, W/C ratio,
dosages of admixtures, specific gravities of materials, and expected mixed volume.
The calculated results are the amounts of various materials, void content, unit weight,
and maximum unit weight. The program can calculate the expected weight of freshly
cast specimens in different molds, and helps to inspect the mixing results. By
comparing the actual sample weight with the expected sample weight, one can tell if
the void content is higher or lower than the expected value. Since the mix volume
contains the volume of voids, a change in design total volume will change the void
content. Since the program set mix volume is an input, the desired void content is
obtained by adjusting the mix volume. Hence, this program can only give expected
values, which might be different with the actual results, which varied with
compaction method. Nonetheless, it provides a guidance of pervious concrete mix

67

design and helps to evaluate approximate void content immediately after sample
being cast.

Figure 4.2. Pervious Concrete Mix Calculation Program

Based on the previous studies, the main index of mix design such as void
content, W/C ratio, A/C ratio, amount of fly ash used in this research followed the
principles discussed below.

68

4.2.2.1 Void Content
Typically void content between 15% and 20% was the optimum range for
pervious concrete to have satisfied permeability and compressive strength23. Most
specimens in this research were compacted with void content in this optimum range.
Some samples were compacted to smaller void content.
4.2.2.2 Fine Aggregates
The amount of sand used in these experiments was 5% by weight of total
aggregate. This percentage was within the limit proposed by Wang et al.10, who
suggested that using a sand content less than 7% by weight improved the compressive
strength without affecting the permeability dramatically. The amount of fine
aggregate was finally decided after finalizing the A/C, W/C, cement amount and void
content.
4.2.2.3 Cement
Since less sand is used in the production of pervious concrete than in
conventional concrete, the surface area of the total aggregate is less than in
conventional concrete. Hence, the amount of cement could be decreased accordingly.
In addition, if a larger size aggregate is used, the amount of cement can also be
decreased because of the decrease of total aggregate surface area. Adjusting the
amount of cement made mix design more economic because of the efficient
utilization of cement. Moreover, the amount of cement was varied with the amount of
fly ash. Typically, the total cementitious material was designed to be between
69

450lb/yd3 to 700lb/yd3,36,37,38. In this research, the amount of total cementitious
material ranged between 430lb/yd3 to 630lb/yd3.
4.2.2.4 W/C Ratio and A/C Ratio
In general, A/C ratio can be calculated by either volume or weight. In this
study, the A/C ratio was calculated by weight. The optimum W/C and A/C ratio
should be determined for the mix so that cement past can cover all surface of
aggregate. The amount of paste should be in the range that provides not only enough
bond but also high void content, which can develop both high compressive strength
and permeability.
Even in conventional concrete, the precise W/C ratio is hard to obtain.
McIntosh (adapted from Kett68) explained the reason for this difficulty: “because the
water in the damp aggregate occurs partly on the surface of the particles and partly
absorbed into the pores where it is not readily available for affecting the properties of
the concrete.” Furthermore, “Even if the absorption characteristics of the aggregated
are known in some detail, it is still not possible to assess accurately the amount of
water absorbed by the aggregate in a mix: the absorption varies with time and it
depends one the degree of saturation of the aggregate before mixing and on whether
the particles are surrounded by water, as in the absorption test, or by a cement paste,
as in concrete” (McIntosh adapted from Kett68).
The difficulty in achieving a precise W/C ratio is increased in pervious
concrete because the “low W/C of these mixtures makes them very sensitive to
atmospheric conditions and small changes in moisture conditions, including the
70

moisture condition of aggregates before mixing”18. In the brochure published by
NRMCA32, a range of 0.35 to 0.45 of W/C ratio was given as a typical ratio for
pervious concrete. It also pointed out that since pervious concrete was very sensitive
to the water content, field adjustment of the freshly mixture was usually necessary.
The W/C ratio used in laboratory tests typically ranged from 0.22 to 0.356,9,10,12. By
reviewing the values stated above, a W/C ratio ranging from 0.32 to 0.37 was used in
this research because pervious concrete with W/C ratio in this range showed satisfied
permeability and compressive strength6,9,10,12.
Compared to W/C ratio, A/C ratio was easier to determine. The National
Concrete Ready Mixed Association recommends a typical A/C range of 4.0~4.5:1.
However, based on the laboratory research and actual project statistics, a range of
4.3~7.3:1 is normally used6,9,10,12. In this research, the A/C ratio was limited to a
range of 4.2~ 4.8:1.

4.2.3 Mixing Equipment
Two concrete mixers are introduced in this section and the selection of mixer
depended on the purpose and the quality of mixing pervious concrete. The first, a 20
quart Blakeslee Mixer, is shown in Figure 4.3. This mixer has advantage of mixing
small batches of conventional concrete, especially useful for laboratory purposes.
However, the mixer was not suitable for mixing consistent batches of pervious
concrete. The friction between blender and aggregates may decrease the strength of
bond between aggregates.

71

Figure 4.3. 20 quart Blakeslee Mixer

Uncovered
gravel

Balls formed
by sand and
cement

Figure 4.4. Specimen Mixed Using 20 Quart Blakeslee Mixer

72

A sample mixed by the Blakeslee Mixer is shown in Figure 4.4. As shown,
some gravel was not covered by cement, and small balls which were composed by
cement and sand were distributed through the sample. Although the usage of the
Blakeslee Mixer indicated worse quality than expected, one set of results were listed
and compared with those mixed by the other mixer.
The other mixer is a 3.4ft3 capacity Gilson 39555 (drum speed 22 ~ 25 RPM)
shown as Figure 4.5. According to the mixing process guidelines, the volume of
mixing material should fill in at least 1/3 of the volume of the container so that the
materials can be evenly mixed.

Figure 4.5. 3.4ft3 capacity Gilson 39555 (drum speed speed 22 ~ 25 RPM)

73

4.2.4 Specimen Mold
The freshly mixed pervious concrete was cast in 4in x 8in cylinders for
compressive strength tests and 3in x 6in cylinders for permeability tests.

4.3 Mixing Procedure
The mixing procedure for the pervious concrete is not specified as it is for
conventional concrete. However, researchers have modified some conventional
concrete mixing procedures to get high quality of pervious concrete. After reviewing
articles10,68 and ASTM standards C 19269, the following mixing steps are used in this
research:
(1) Mix a small amount of cement (<5% by mass) with coarse aggregate for about
1min;
(2) Add sand, admixtures (disolved in water), and the remaining cement and water;
(3) Mix for 3min, rest for 3min, and finally mix for another 2min;
Before adding the materials, small amount of water and cement with the
design W/C ratio was put into the mixer and mix for 5 seconds. In this way, the inside
surface of mixer was covered by a thin layer of cement, decreasing amount of
material lost during the mixing. The water content was adjusted by observing the
fluidity of the mix. The mix was accepted when the concrete could be formed into a
ball after being tightly squeezed by hand for 10 seconds, and the ball separated when
was thrown onto the mix, and the adhesive residues coated around 50% of the palm;
the concrete mix that achieved these two conditions indicated that the mix had
appropriate water content (Hunt70, personal communication]). These conditions were
74

important criteria for detecting the quality of pervious concrete mix. Either higher or
lower water content may cause worse quality and decrease the permeability or
compressive strength of pervious concrete. This method had been routinely used to
inspect the quality of pervious concrete mix (Hunt 70, personal communication).

4.4 Compaction Method
Different compaction methods as listed in Table 4.8 were used to obtain best
compaction results. Rodding, standard Proctor hammer, jigging and dropping
methods were all used and their effects were compared. The samples compacted by
different methods are shown in Table 4.9.

Compaction Method ID
Rod-10/3
Jig-25/2*
Proct-5/3
Drop-5/3
Drop-10/3
Drop-15/3

Note
Rodding 10 times/layer, 3 layers
Jigging 25times/layer, 2 layers*
Proctor hammer compacting 5times/layer, 3 layers
Dropping with 2~3in height 5times/layer, 3 layers
Dropping with 2~3in height 10times/layer, 3 layers
Dropping with 2~3in height 15times/layer, 3 layers

Table 4.8 Compaction Method ID Explanation
Note: *Buckeye Ready-mix Corp.

75

Mix ID
#1 AC46-FA00-WC27-5SD

Compaction Method ID
Rod-10/3

#2 AC46-FA30-WC22-5SD

Rod-10/3

#3 AC48-FA09-WC37-0SD*

Jig-25/3

#4 AC48-FA30-WC32-5SD

Drop-10/3
Proct-5/3

#5 AC43-FA02-WC34-5SD

Drop-5/3
Drop-10/3
Drop-15/3
Proct-5/3

#6 AC45-FA32-WC34-5SD

Drop-5/3
Drop-10/3
Drop-15/3

Table 4.9. Pervious Concrete Mixes Compacted Using Different Methods Mix
Note: *Samples Obtained from Buckeye Ready-mix Corp.

4.5 Curing Method
The curing of pervious concrete samples followed ASTM C 19269. The
samples were removed from their molds and cured in a water tank at 72.5 ± 3.5 oF
[23.0 ± 2.0 oC]. Two temperature bars and an electronic blower were immersed in
water tank to maintain the temperature and uniformed heat distribution. The molds
were removed after 7-day curing period (suggestion from Pardi71, personal contact).
In addition, 6 layers of polyethylene plastic sheets were used to cover the surface of
molds to prevent water from evaporating. The thickness of plastic coverage was
larger than 6mil (0.006in), which satisfies the requirement specified in ASTM C 31 /
C31M - 0972.
76

4.6 Laboratory Tests
Unit weight, void content, compressive strength test, and permeability test
were carried out in this study. All the tests followed ASTM standards28,73,74,75,76,77, 78,79.

4.6.1 Unit Weight and Void Content
The unit weight and void content were obtained following the ASTM C
1688/C 1688M35. The unit weight introduced in this study was freshly mixed
pervious concrete unit weight, which is obtained right after samples are cast. Equation
4-1 from ASTM C 1688/C 1688M - 0835 was used to calculate the unit weight.

D = (Mc – Mm)/Vm

(Equation 4-1)

Where:
D = density or unit weight of concrete, lb/ft3.
Mc = mass of mold filled with concrete, lb.
Mm = Mass of mold, lb.
Vm = Volume of mold, ft3.

77

The Void Content was calculated using Equation 4-2:
U = [(T – D)/T] * 100%

(Equation 4-2)

Where:
U = percentage of voids in the fresh pervious concrete.
T = theoretical density of the concrete computed on an airfree basis,
lb/ft3.
D = density or unit weight of concrete, lb/ft3.

The air free density was calculated from Equation 4-3
T = MS/VS

(Equation 4-3)

Where :
MS = total mass of all materials batched, lb.
VS = sum of the absolute volume of the component ingredients in the
batch, ft3.

78

Material

Specific Gravity

#8 River Gravel (SSD)

2.63

Sand

2.61

Cement type I

3.15

Class F Fly Ash

2.1

Fiberstrand 100

0.91

PLASTOL 6200 EXT

1.08

EUCON W.O

1.12

EUCON MRX

1.12

Visctrol

1.21

Table 4.10. Specific Gravities of Materials in Portland Cement Pervious Concrete
Mix

The theoretical density was constant for each batch of concrete mix and was
calculated in the pervious concrete mix calculation program (Figure 4.2). The total
absolute volume was the sum of each material volume, which was calculated by
multiplying the mass by the specific gravity. In this study Saturated Surface Dry
(SSD) specific gravity of coarse aggregate and specific gravities of sand, cement, and
fly ash listed in Table 4.10 were used.

4.6.2 Compressive Strength
Compressive strength testing followed ASTM C 3928. The testing machine
was INSTRON-5585 as shown in Figure 4.6 with maximum capacity of 300kN
(67,400lb).

79

Figure 4.6. INSTRON-5585 Compressive Strength Testing Machine

The specimens with curing period of 7, 21, and 28 days were tested for
compressive strength. For specimens with uneven surfaces, capping was used to
minimize the effect of stress concentration. In addition, two steel caps with rubber
cushion were placed on the top and the bottom of each specimen during the
compressive strength test.

4.6.3 Permeability
The permeability of pervious concrete was investigated using a modified
falling head permeability test. A simple permeameter system as illustrated in

80

Figure 4.7 was developed to measure the hydraulic conductivity of pervious concrete.
The specimen as shown in Figure 4.8 was tightly covered by two layers of side-sealed
plastic sheet to prohibit the water from flowing through the side voids. Layers of
rubber membranes were placed around the top of specimen to enclose the space
between specimen and PVC pipe. Ideally, the specimen was stuck in the pipe at some
location, where the bottom of specimen was untouched with the PVC joint 1 so that
the hydraulic conductivity was not affected by the change of cross section of PVC
joint 1. The rubber membranes and plastic sheets effectively ensured the water
flowed vertically through the specimen. The falling head Equation 4-4 was used in
the calculation of coefficient of permeability

k = (aL/At) * ln(∆h0/∆h1)

(Equation 4-4) (ASTM D 508479)

Where:
k = coefficient of permeability, in/sec.
a = cross sectional area of the standpipe, in2.
L = length of sample, in.
A = cross sectional area of specimen, in2.
t = time in seconds from ∆h0 to ∆h1.
∆h0 = initial water level, in.
∆h1 = final water level, in.

.

81

Inlet
Specimen Position
PVC joint 1
Outlet

PVC valve

Figure 4.7. Falling Head Permeability Test for Pervious Concrete Specimen

Rubber
Membranes

Figure 4.8. Pervious Concrete Specimen for Permeability Test
82

4.7 Summary of Test Procedure
The pervious concrete mix design and laboratory tests are introduced in this
chapter. The mixing materials used in this research were #8 river gravel, type I
cement, sand, HRWR, MRWR, water retarder, viscosity modifying admixture and
sand. To investigate the effect of substituting fly ash for cement on compressive
strength and permeability of pervious concrete, mixes #2 and #6 were designed to
contain 30% more fly ash and 30% less cement than mixes #5 and #1. Sand is used in
each batch to increase the compressive strength of pervious concrete, and weighted
5% of total aggregates. A pervious concrete mix calculation program was developed
to calculate the design values of unit weight and maximum weight of pervious
concrete mix.
A 3.4ft3 capacity drum mixer filled with approximate 1.2ft3 of pervious
concrete was used in the mix. When mixing process was finished, pervious concrete
was casted to 4in x 8in cylindrical samples for compressive strength test, and 3in x
6in cylindrical samples for permeability tests. The unit weight and void content were
calculated from the mass, volume, and air free density of each pervious concrete
sample, according to ASTM C 168835. Compressive strength tests on specimens with
7, 21, and 28 curing periods were carried out following ASTM C 3931. Capping was
used on specimens in the compressive strength test to help the compressive stress be
evenly distributed. A modified falling head permeability test was carried out on
specimens with various void contents from mixes #5 and #6 so that the relationship
between void content and permeability, and the effect of fly ash on permeability of
pervious concrete may be obtained from the test results.
83

64

QUIKRETE. (2010). “Sand and gravels material safety data sheet.”
QUIKRETE, http://www.quikrete.com/PDFs/MSDS-B1-SandAndGravel.pdf>
(June, 2010).
65

ASTM C 150. (2009). “Standard specification for Portland cement.” ASTM
international, DOI: 10.1520/C0150_C0150M-09,
<http://www.astm.org/Standards/C150.htm> (June 30, 2010).
66

Walker, H. W., Taerakul, P., Butalia, T. S., Wolfe, W. E., and Dick, W. A.
(2001). “Minimizaiton and use of Coal Combustion By-products (CCBs):
concepts and applications, adapted from “Handbook of pollution control and
waste minimization.” New Mexico State University, Marcel Dekker, Inc.,
Ghassemi ed., p. 426.
67

ACI Committee 211. (2002). “Standard Practice for Selecting Proportions for
Normal, Heavyweight, and Mass Concrete”, ACI 211.1-91, reapproved 2002.
68

Kett, I. (1999). “Engineered concrete mix design and test methods.” CRC Press,
1st edition, p. 5-10.
69

ASTM C 192. (2007). “Standard practice for making and curing concrete test
specimens in the laboratory.” ASTM international, DOI:
10.1520/C0192_C0192M-07, <http://www.astm.org/Standards/C192.htm> (June
30, 2010).
70

Hunt, D. (2009). “Pervious concrete yield test.” Buckeye Ready Mix, personal
communication.
71

Pardi, M. (2010). National Mix Concrete, personal communication.

72

ASTM C31 / C31M. (2008). “Standard practice for making and curing concrete
test specimens in the field.” ASTM international, DOI: 10.520/C0031_C0031M09, <http://www.astm.org/Standards/C31.htm> (June 30, 2010).
73

ASTM C 29. (2009). “Standard test method for bulk density (“unit weight”)
and voids in aggregate.” ASTM international, DOI: 10.1520/C0029_C0029M-09,
<http://www.astm.org/Standards/C29.htm> (June 30, 2010).
74

ASTM C 94. (2009). “Standard specification for Ready-Mix Concrete.” ASTM
international, DOI: 10. 1520/C0094_C0094M-09A,
<http://www.astm.org/Standards/C94.htm> (June 30, 2010).

84

75

ASTM C 125. (2009). “Standard terminology relating to concrete and concrete
aggregates.” ASTM international, DOI: 10.1520/C0125-09A,
<http://www.astm.org/Standards/C125.htm> (June 30, 2010).
76

ASTM C 127. (2007). “Standard test method for density, relative density
(specific gravity) and absorption of coarse aggregate.” ASTM international, DOI:
10.1520/C0127-07, <http://www.astm.org/Standards/C127.htm> (June 30, 2010).
77

ASTM C 138. (2009). “Standard test method for density (unity weight) yield,
and air content (gravimetric) of concrete.” ASTM international, DOI:
10.1520/C0138_C0138M-09, <http://www.astm.org/Standards/C138.htm> (June
30, 2010).
78

ASTM C 617. (2009). “Standard practice for capping cylindrical concrete
specimens.” ASTM international, DOI: 10.1520/C0617-09A,
<http://www.astm.org/Standards/C617.htm> (June 30, 2010).
79

ASTM D 5084-03 (2003). “Standard test methods for measurement of
hydraulic conductivity of saturated porous materials using a flexible wall
permeameter.” ASTM international, DOI: 10.1520/D5084-03,
<http://www.astm.org/Standards/D5084.htm> (June 30, 2010).

85

CHAPTER 5
DISCUSSION ON TEST RESULTS

5.1 Introduction
Test results are presented and discussed in this chapter. The compressive
strength test results on mixes #1, #2, #3, #4, #5, #6 and permeability test results on
mixes #5, #6 are discussed.

5.2 Void Content vs. Unit Weight
The relationship between void content and unit weight is shown in Figure 5.1.
For each batch of pervious concrete, the unit weight decreased with the increase of
void content up to 30%, after which it remained approximately stable. As shown in
Figure 5.1, the specimens from mix #1, #3, and #5 had higher predicted unit weight
than those from mix #2, #4, and #6 at the same void content. This can be explained by
various fly ash and cement content in the mixes. The fly ash in mix #2, #4, #6
substituted 30% amount of cement, while no or very little fly ash was used in mix #1,
#3, and #5. Since cement has higher specific gravity than fly ash, the weight of
specimens is correspondingly higher. Furthermore, at the same W/C ratio, mix #5 had
lower A/C ratio and higher unit weight than mix #6, indicating that low A/C ratio
may generate higher unit weight.

86

3

Void Content (%) vs. Unit Weight (lb/ft )
150

Unit Weight (lb/ft 3)

140

#1 AC46-FA00-WC27-5SD
#2 AC46-FA30-WC22-5SD

130

#3 AC48-FA09-WC37-0SD
#4 AC48-FA30-WC32-5SD

120

#5 AC43-FA02-WC34-5SD
#6 AC45-FA32-WC34-5SD

110

100
10%

15%

20%

25%

30%

35%

40%

45%

Void Content (%)

Figure 5.1. Relationship between Void Content (%) and Unit Weight (lb/ft3)

5.3 Effect of Compaction Energy
This section discusses the effect of various compaction methods. The average
void content of specimens compacted at different methods are illustrated in Figure 5.2.

87

Void Content vs. Compaction Method

Void Content (%)

Rod-10/3

Proct-5/3

Drop-5/3

Drop-10/3

Drop-15/3

45%
40%
35%
30%
25%
20%
15%
10%
5%
0%
#1 AC46FA00-WC275SD

#2 AC46FA30-WC225SD

#4 AC48FA30-WC325SD

#5 AC43FA02-WC345SD

#6 AC45FA32-WC345SD

Pervious Concrete Mix ID

Figure 5.2. Void Contents of Specimens Compacted by Different Methods

As shown in Figure 5.2, the specimens compacted by rodding method had
higher void content. This void content was out of the typical range of 15%~25%
specified by NRMCA2, and was too high for pervious concrete to reach acceptable
compressive strength. Hence, the rodding method Rod-10/3 is not recommended to
compact the pervious concrete test samples. Comparatively, the Proctor hammer and
the dropping methods generated good compaction results with void content ranges
from 12% to 25%. In addition, void contents of specimens from mix #5 and #6
indicated that void content was decreasing with the increase of compaction energy
generated by method of Drop-5/3, Drop-10/3 and Drop-15/3.
88

Compared to standard Proctor hammer compacting, the dropping method was
preferred because it caused less disturbance to the cement bond. Proctor hammer may
cause low strength of bonding interface between layers. As illustrated in Figure 5.3,
the specimen compacted by standard Proctor hammer showed apparent interface
between different layers. And at failure, aggregates at the interface popped out,
indicating the low strength of bond at the interfaces.

Compact
layer
interface

Figure 5.3. The Specimen Compacted by Proctor Hammer

89

5.4 Effect of W/C Ratio, A/C Ratio and Fly Ash on Void Content
As illustrated in Figure 5.2, specimens from mix #4, #5, and #6 had different
average void contents when using the same compaction method Drop-10/3.
Specimens from mix #5 had the lowest void content; while those from mix #4 had the
largest void content. This can be explained by different A/C ratio, W/C ratio and fly
ash content in these mixes. The mix #5 had lowest A/C ratio, lowest fly ash content
and higher W/C ratio, which could be expected to results in the lowest void content.
Mix #6 had A/C ratio that was greater than mix #5 and less than mix #4, fly ash
content that was less than mix #5 and similar to mix #4, and W/C ratio that was
higher than mix #4. These differences generated void content that was higher than in
#5 and lower than in #4 for specimens in #6. The results showed that lower A/C ratio,
lower fly ash content, and higher W/C ratio resulted in lower void contents.
Furthermore, the effects of A/C, W/C and fly ash content on void content were
consistent with those for unit weight as discussed in section 4.2.

5.5 Compressive Strength
This section discusses the effect of curing period, void content and mix design
on compressive strength of pervious concrete. The compressive strength results of
specimens from two sets of mix batches mix #5 and mix #6 are discussed and
compared in detail. The comparison helps to investigate the compressive property of
the pervious concrete that had large fly ash content which was 32% of the total
cementitious material.

90

5.5.1 Compressive Strength vs. Curing Period
The increasing compressive strengths with curing period of representative
specimens are shown in Figure 5.4. The specimens were from batches of mix #3, #4,
#5, #6, and had different void contents. The compressive strength of specimens from
each mix indicated similar trends. However, the strength increased slightly different
for specimens with different fly ash content. For the curing period of 7 and 21 days,
the compressive strength of specimens from mix #3 and #5 had higher rate of increase
than did those from mix #4 and #6. However, from 21-day curing period to 28-day
curing period, the compressive strength of specimens from mix #3 and #5 increased
more slowly than those from mixes #4 and #6, which had approximate 30% more
amount of fly ash than mix #3 and mix #5, respectively. This indicates that the
addition of fly ash improved the long-term strength of the pervious concrete mix. The
trendlines in Figure 5.4 are consistent with those illustrated in Figure 3.5.

91

Unconfined Compressive Strength (psi)

Compressive Strength vs. Curing Period at Different Void Content
3200
#3 AC48-FA09WC37-0SD (Buckeye
Readymix) e=31%

2800
2400

#4 AC48-FA30WC32-5SD e=27%

2000
1600

#5 AC43-FA02WC34-5SD e=14%

1200
800

#6 AC45-FA32WC34-5SD e=18%

400
0
0

7

14

21

28

Curing Period (Days)

Figure 5.4. Pervious Concrete Mix #3~#6 Compressive Strength vs. Curing Period

5.5.2 Compressive Strength vs. Void Content
The relationship between 28-day compressive strength and void content is
demonstrated in Figure 5.5. The compressive strength fell in a range between 800psi
and 3,200psi. The pervious concrete with 2% of fly ash reached the highest
compressive strength which was greater than 3,200psi; while the highest value that
the mix with 32% fly ash achieved was only 1700psi. The compressive strength of the
specimen with 2% fly ash exceeded the capacity of the load, from so the strength
reported is actually at lower bound number. However an earlier test on the same
modified indicated a compressive strength of 3,114 psi. So it was acceptable that the
specimen had compressive strength close to 3,200psi.
92

Although six batches had different mix designs, the compressive strength tests
on all specimens indicated the same trend that the compressive strength decreased
with increase in void content, as indicated in Figure 5.5. One reason that the
specimens from mix #5 had the higher compressive strength was they had the lower
void contents. By observing the trend of compressive strength, it was possible for
specimens from mix #6, in which fly ash content counted for 32% of total
cementitious material, to reach the compressive strength over 2,000psi with void
content around 15%. The tests do not indicate the void content at which the
compressive strength would reach 3,000psi. Although the compressive strength could
reach to 3,000psi, the void content might be too small to satisfy the requirement of
permeability.

28-day Compressive Strength (psi)

28-day Compressive Strength vs. Void Content
3500
3000
2500
#1 AC46-FA00-WC27-5SD
2000

#2 AC46-FA30-WC22-5SD
#3 AC48-FA09-WC37-0SD

1500

#4 AC48-FA30-WC32-5SD
1000

#5 AC43-FA02-WC34-5SD
#6 AC45-FA32-WC34-5SD

500
0
10%

15%

20%

25%

30%

35%

40%

45%

Void Content (%)

Figure 5.5. Relaiton between 28-day Compressive Strength and Void Content

93

5.5.3 Compressive Strength vs. Unit Weight

28-day Compressive Strength (psi)

28-day Compressive Strength vs. Unit Weight
3500
3000
2500
#3 AC48-FA09-WC37-0SD

2000

#4 AC48-FA30-WC32-5SD
#5 AC43-FA02-WC34-5SD

1500

#6 AC45-FA32-WC34-5SD

1000
500
0
100.0

120.0

140.0

Unit Weight (lb/ft3)

Figure 5.6. Relationship between 28-day Compressive Strength and Unit Weight

The relationship between 28-day compressive strength and unit weight is
shown in Figure 5.6. Apparently, the compressive strength increased with the
increment of unit weight, corresponding to the decrease of void content.

5.5.4 Compressive Stress-strain Curves vs. Void Content
Stress-strain curves of specimens from mix #5 and mix #6 are presented in
this section. However, the strains shown in curves were not actual values of the
strains of pervious concrete specimens. As introduced in Chapter 4, since two rubber
caps were used to decrease the effect of stress concentration, large strains were
developed due to the high elasticity of rubber during the process of compression,
94

especially at the initial status. In another word, the strains shown in stress-strain
curves were the total strains from both rubber and specimens. As illustrated in Figure
5.7 and Figure 5.8, the stress-strain curves showed dramatic increases after
experienced relatively large strains under low stresses. The large strains were
expected caused by the rubbers, which have lower elastic modulus than that of
pervious concrete. The strains caused by rubbers were expected to be the strain values
at the point, at which stress began to increase faster with smaller strains generated. As
shown in Figure 5.7 and Figure 5.8, the strains caused by rubbers were approximately
expected to be 1%~2%. Hence, the strains of concrete specimens were obtained by
subtracting the total strains by 1%~2%.

95

28-day Stress vs. Strain Curves, Mix #5
U=12%

U=12%

U=13%

U=14%

3500
U=12% Su=3114psi

U=12% Su>3183psi

3000
U=13% Su=2705psi

Stress (psi)

2500

U=14% Su=1989psi

2000
1500
1000
500
0
0.0%

1.0%

2.0%

3.0%

4.0%

5.0%

6.0%

7.0%

Strain (%)

Figure 5.7. Stress-strain Curves Tested on Specimens with Different Void Content at
28-day Curing Period, Mix #5

96

28-day Stress vs. Strain Curves, Mix #6
U=18%

U=20%

U=24%

2000
U=18% Su=1714psi
U=20% Su=1432psi

Stress (psi)

1500

U=24% Su=1296psi

1000

500

0
0.0%

1.0%

2.0%

3.0%

4.0%

5.0%

6.0%

7.0%

Strain (%)

Figure 5.8. Stress-strain Curves Tested on Specimens with Different Void Content at
28-day Curing Period, Mix #6

Figure 5.7 and Figure 5.8 demonstrate the different failure process of
specimens with 28-day cured period from mix #5 and mix #6, respectively. As shown,
for those results from the same batch of mix, brittle failures happened in specimens
with lower void contents; while the specimens that had greater void content behaved
in a plastic manner. The representative examples were specimen with U=12% from
mix #5, and the specimen with U=24% from mix #6. The specimen with U=12%
failed suddenly after it had reached to the strength; while the stress-strain curves of
the later one rebounded several times before and after reaching to the maximum stress.
This ductile failure mode might be explained by the rearrangement of particles during
97

compression. Since voids existed in pervious concrete specimens, the aggregates were
rearranged and filled some voids after initial peak. This helped specimens to sustain
higher loads after partial failure. Consequently, when load kept increasing, the
process occurred again. Therefore, these recycling processes formed serrated stressstrain curves. However, for specimens with low initial void content, specimen had
already experienced very high compressive load at initial peak. Although some stress
may be released by cracks, the load was still out of the capacity of rearranged
structure of the specimen. Hence, failure happened in brittle mode when loads
reached to the strength.

5.5.5 Compressive Failure vs. Curing Period
Figure 5.9 illustrates the failure modes of specimens with 18% void content at
7-day, 21-day, and 28-day curing periods. The compressive strength of specimens
with 7-day curing period showed more apparent rebounds than those with longer
curing periods. The difference in failure modes may be caused by the difference in
the strength of the cement bond. At the early age, the strength of cement bond had not
been fully developed due to the uncompleted cement hydration process. Hence,
breaks were easier to occur at the interface between aggregate, followed by the
release of stress and rearrangement of aggregates. Consequently, the compressive
capacity increased and rebound line occurred.

98

7-day, 21-day, and 28-day Stress vs. Strain Curves (U = 18%), Mix #6
7-day

21-day

28-day

2000
28-day Su = 1714psi

21-day Su = 1413psi

Stress (psi)

1500

7-day Su = 1323psi

1000

500

0
0.0%

1.0%

2.0%

3.0%

4.0%

5.0%

6.0%

7.0%

8.0%

Strain (%)

Figure 5.9. Stress-strain Curves Tested on Specimens with Void Content 18% at 7day, 21-day, and 28-day Curing Periods, Mix #6

5.5.6 Failure Modes

99

Figure 5.10. Failure Mode I of Pervious Concrete Samples

Figure 5.11. Failure Mode II of Pervious Concrete Samples

Figure 5.10 and Figure 5.11 illustrate the typical failure modes for the
pervious concrete specimens. Failure mode I and II matched the ASTM C 3928 well100

defined fracture patterns of Type 1 (reasonably well-formed cones on both ends, less
than 1 in. of cracking through caps) and Type 2 (well-formed cone on one end,
vertical cracks running through cracks running through caps, no well-defined cone on
the other end), respectively.

Figure 5.12. Failure of Specimen Compacted by Standard Proctor Hammer (Mix #6)

Figure 5.12 illustrates the unacceptable failure of specimen from mix #6. The
failure indicated the low strength of interface between compacted layers caused by
Proctor hammer.

101

Exposed
gravel
surface

Mix #5

Mix #6

Figure 5.13. Failure Surface Comparison between Specimen from Mix #5 and Mix #6

Figure 5.13 illustrates the difference of failure surfaces between the specimens
from mix #5 in which fly ash counted for 2% of total cementitous materials and the
one from mix #6 that had 32% of fly ash. As shown in mix #5, the failure surface
mainly passed through coarse aggregates instead of the interface between aggregate,
indicating the good bonding effect generated by cement. In contrast, the failure
surface of specimen from mix #6 showed more separation between aggregates, which
implied lower strength of bond than that in mix #5. This might be caused by two
reasons: firstly, the spherical shape of fly ash may cause poor bonding characteristics;
secondly, the cement content was not enough for fly ash to form more CSH bond.

102

5.6 Permeability
Permeability tests were conducted on specimens from mix #5 and mix #6. The
permeability fell in a range of 0.13~0.5cm/s for specimens with void content in a
range of 14.8% to 25.6%. The values satisfied the general minimum requirement for
pervious concrete permeability which is 0.1cm/s. In addition, the permeability was
proportional with the void content of specimens as shown in Figure 5.14. This agreed
with the studies from pervious studies as discussed in Chapter 2.

Void Content (% ) vs. Permeability (cm/s)
#5 AC43-FA02-WC34-5SD

#6 AC45-FA32-WC34-5SD

Permeability (cm/s)

0.60
0.50
0.40
0.30
0.20
0.10
0.00
10.0

15.0

20.0

25.0

30.0

Void Content (%)

Figure 5.14. Relationship between Void Content and Permeability of Pervious
Concrete Specimens

103

Figure 5.14 shows consistent relationship between void content and
permeability of specimens from mix #5 and #6. This indicated that except for fly ash
content, the permeability may be determined from the void content, regardless of
other differences in mix designs except fly ash content. The main difference between
mix #5 and mix #6 was the fly ash and cement content. Mix #6 had 30% more fly ash
and 30% less cement than mix #5. The permeability tests result indicated that the fly
ash content did not significantly affect the permeability of pervious concrete. This
was different with the effect of fly ash on conventional concrete. As discussed in
Chapter 3, fly ash decreases the permeability of concrete because it blocks the
capillaries when reacting with free lime to form CSH. However, this effect might be
minimal in pervious concrete because it has capillaries with large diameters. In
addition, the replacement of large portion of fly ash for cement may improve the
permeability of pervious concrete. Since large portion of cement has been replaced by
fly ash, not enough free lime could be developed during the process of the cement
hydration. Consequently, portions of fly ash can not react with free lime to form CSH
bond and block the capillaries in pervious concrete. The spherical shape of fly ash
may also contribute to the improvement of the permeability. This possibility was
demonstrated by the permeability test results on specimens with void content that
approximately equaled to 16%, as shown in Figure 5.14.
In order to further examine the permeability test, the results were compared
with those from pervious studies. As shown in Figure 5.15, the measured values were
in coordinating with the results from previous studies. Among these studies, Montes
and Haselbach25 proposed permeability as a function of void content as discussed in
104

Chapter 2. The calculated values are presented in Figure 5.15 and show relatively
good prediction of permeability for most specimens with void content in a range of
10% ~ 30%. Although the measured values of permeability in this research were
generally higher than the calculated results, they showed approximate agreement.
Hence, the formula presented by Montes and Haselbach25 can be used in this study.
Although Montes and Haselbach25 declared the application of the formula to be
limited to that specific research, in which the size of aggregate was 3/8 inches~5/8
inches and the porosity was in a range of 15%~32%, this study showed the formula
can also be used for the size of aggregate between 3/8 inches and ½ inches . Although
no existing standards are available to investigate the permeability test of pervious
concrete, the testing method used in this research generated reasonable values that fell
in the range of previous testing results. Figure 5.15 indicates the validity of the test
method.

105

Void Content (% ) vs. Permeability (cm/s)
Literature Review
#5 AC43-FA02-WC34-5SD
Power (Montes(2006) Ks = 18 *p3 / (1-p)2)

Montes(2006) Ks = 18 *p3 / (1-p)2
#6 AC45-FA32-WC34-5SD

Permeability (cm/s)

4.00

3.00

2.00

1.00

0.00
0

5

10

15

20

25

30

35

40

45

Void Content (%)

Figure 5.15. Comparison of Permeability Test Results with Previous Studies

106

CHAPTER 6
SUMMARY, CONCLUSION, AND RECOMMENDATIONS

6.1 Summary
The use of pervious concrete is encouraged by the NRMCA2 because of its
benefits in stormwater management, reduction of heat island effect, decreased traffic
noise, and potential for earning LEED credits. Furthermore, fly ash is used to replace
portion of Portland cement, enhancing the sustainability of pervious concrete. This
study was oriented by the large portion replacement of cement by fly ash, including
the investigation of the effects of factors on the bearing capacity and hydraulic
conductivity of the pervious concrete.
Several mix designs were proposed, containing different W/C ratios, A/C
ratios, and fly ash content. The mix design that contained 2% fly ash was carried out
to obtain the desirable mechanical properties and satisfied permeability. High
compressive strength was obtained, and the mix design was taken as the base for the
other batch of pervious concrete, in which 32% of cement by weight was replaced by
fly ash. Meanwhile, the W/C ratio and A/C ratio were remained constant or slightly
different. Moreover, specimens from two mix designs were compacted with the same
compaction energy. With all these restrictions, the test results from these two mix

107

batches were compared and the applicability of large portion of fly ash in pervious
concrete will be discussed.
Although the six batches of pervious concrete had different mix designs,
another reason that the compressive strength showed scattered values was because of
the limited knowledge and experience in pervious concrete mixing. The operation of
mixing pervious concrete is more challengeable than that of conventional concrete.
Crew should be trained with certified program to obtain the pervious concrete
acknowledge and minimize the failure of placement 80. In 2005, the NRMCA created
the pervious concrete Contractor Certification Program with three levels of
certification, including technician, installer and craftsman based on the level of
experience that the contractor has in pervious concrete installation81.
The correlations between compressive strength, permeability, and void
content are illustrated in Figure 6.1. The figure indicates that at permeability of
0.1cm/s, the void content of specimens from mix #6 is predicted to be approximate
12.5%, at which the compressive strength may reach to 2,500psi.

108

Figure 6.1. Permeability and 28-day Compressive Strength vs. Void Content

6.2 Conclusion
The following conclusions were drawn from this study.
(1) The compressive strength increased with the decrease of void content. The
compressive strength of specimens with 2% fly ash (mix #5) and those with
32% of fly ash (mix #6) increased at different rates. For specimens from mix
#5, compressive strength reached to 2,300psi at the void content of 15%, and
over 3,000psi at void content of 12%; while for specimens from mix #6,
pervious concrete only reached to compressive strength around 2,000psi at
void content of 15%. This indicated that pervious concrete that had large
portion of fly ash (≥ 32%) should be limited to use in low volume traffic road.

109

In this specific study, the mix with 32% fly ash in total cementitious material
was restricted for pavement that sustained load larger than 2000psi.
(2) The laboratory test results showed that less A/C ratio and less fly ash content
generated lower void content and higher unit weight.
(3) The existence of fly ash influenced the increase of compressive strength of
pervious concrete along curing period. Compared to the concrete mix with
2% fly ash, the mix in which 32% of cement was replaced by fly ash had
lower growth rate of compressive strength at the first 21-day curing period;
while had higher rate after that. This indicated that fly ash helped to increase
the late-age compressive strength of pervious concrete.
(4) The permeability decreased with the increase of void content. For specimens
from mix #5, the minimum permeability of 0.13cm/s corresponded to the
void content of 14.9% and the compressive strength of 2,300psi. The
measured permeability was slightly higher than the minimum requirement
which was 0.1cm/s for pervious concrete10. The minimum permeability of
specimen from mix #6 was 0.21cm/s at the void content of 15.8%, indicating
good permeability of pervious concrete that had large portion of fly ash.
(5) The unit weight of pervious concrete decreased with the increase of void
content; while remained constant or slightly changed when void content was
larger than 30%. At the same void content, higher W/C ratio and lower A/C
ratio may generate higher unit weight.
(6) The void content of pervious concrete decreases with the increment of
compaction energy. Compact rodding method was inappropriate to use for
110

pervious concrete. The compaction technique of using Proctor hammer
provided with most constant compaction results. However, the segregation
occurred at the interface of layers during compression. The compaction
method of drop-5/3, drop-10/3, and drop-15/3 method presented in this study
generated relatively consistent value of void contents for specimens, without
forming apparent separation between layers.

6.3 Recommendations for Future Work
As discussed before, due to the difficulty to obtain design void content in
pervious concrete, the compacted specimens may have actual void content that are
different from the design value. Compacted specimens used for compressive strength
test and permeability test may have different void contents. To obtain more precise
conclusions on void content, compressive strength, and permeability, more tests need
to be carried out. In addition, the mix with 32% fly ash had minimum permeability of
0.21cm/s at void content of 15.8%, which had more space to reach to the limit of
0.1cm/s for pervious concrete. A new batch of mix is recommended to perform, in
which the specimens could be compacted with void contents less than 15.8%.
Consequently, the greater compressive strength is expected to be obtained from
specimen that has lower void content and acceptable permeability.
The failure mode of specimens with 32% fly ash showed low strength of paste
bond due to large portion replacement of cement by fly ash. According to the
mechanism that fly ash reacts with free lime to form CSH, free lime is recommended
to use in pervious concrete with large portion of fly ash substitute for Portland cement.
111

Otherwise, extreme high cement content may be required to develop more free lime
during the process of hydration.
80

National Ready Mixed Concrete Association (NRMCA),
<http://www.nrmca.com/certifications/pervious/> (April 24, 2010).
81

Aggregate & Ready Mix Association of Minnesota,
<http://www.armofmn.com/displaycommon.cfm?an=1&subarticlenbr=29> (April
24, 2010).

112

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120

APPENDIX A
EXAMPLES OF PERVIOUS CONCRETE EXPERIMENTS
FROM LITERATURE REVIEW

121

122

Author
Crouch,
L. K.,
et al.
(2007)
Wang,
K. et al.
(2006)

Mix
ID
A
B
C
D
1
2
3
1A
1B
2A
2B
2C
2D
2E
2F
2G
2H
3A
3B

Cement
(lb/yd3)
450
450
375
375
600
600
600
571
520
571
520
520
542
485
600
600
571
571
571

Class C
Fly Ash
(lb/yd3)
131
131
109
109
-

Water
(lb/yd3
)
177
177
147
147
162
162
162
154
114
154
116
114
114
114
162
162
154
154
126

Aggregat
e (lb/yd3)
2,599
2,599
2,731
2,731
2700
2700
2700
2500
2500
2500
2500
2500
2500
2500
2700
2700
2500
2500
2500

W/C
0.3
0.3
0.3
0.3
0.27
0.27
0.27
0.27
0.22
0.27
0.27
0.22
0.22
0.22
0.27
0.27
0.27
0.27
0.22

Table A.1: Examples of Laboratory Tests on Pervious Concrete.

122

A/C
4.47
4.5
5.6
5.6
4.5
4.5
4.5
4.4
4.8
4.4
4.8
4.8
4.6
5.2
4.5
4.5
4.4
4.4
4.4

Unit
Weight
(lb/ft3)
116.9
117.5
104.1
130.9
127.7
126.8
120.3
232.2
120.4
119.4
122.5
119.8
-

Void
Content
(%)
12~33
23~37
27~39
26~37
28.8
25.3
33.6
20.5
18.3
19
26
14.1
18.9
22.1
19
23
-

28-day
Compressiv
e
Strength(ps
i)
1800~7500
1450~4600
1000~3500
870~2900
2506
1722
3661
2969
1307
2735
3106
3106
3849
-

Permea
bility
(in/sec)
0.1
0.57
0.19
0.04
0.07
0.02
0.11
0.27
0.12
0.09
Continued

123

Table A.1. continued
T1
T2
T3
T4
Yang
T5
and
T6
Jiang,
T7(+S
et al.
F)
(2003)
T8(+
VAE)
T9(+P
AF)
Fortes
1BT
510
(2008)
2BT
607
3BT
627
R2T
R3T
617
R4T
617

-

-

-

0.33
0.35
0.35
0.28
0.22
0.2

-

114.8
121.5
115.6
131.1
128
117.4

-

1030
1420
2000
2900
5150
3872

3.07
3.27
3.5
0.74
1.14
7.87

-

-

-

0.2

-

134.5

-

8200

0.67

-

-

-

0.28

-

144.5

-

8800

0.12

-

148
158
257
222
210

-

0.35
0.29
0.26
0.41
0.39
0.36
0.34

-

138
164
164
158
139
144
154

-

7550
1700
3870
3870
2550
3050
3280

0.9
0.01
0.39
0.43
1.14
-

123

124

Project
Informa
tion
Hein and
Schindle
r (2006),
Auburn
Universi
ty

Class C
Fly Ash
(lb/yd3)

Coarse
Coarse
Water Cement
Aggrega Aggregat
te
e (lb/yd3)
(lb/yd3) (lb/yd3)
No. 7
183
600
gravel
2391
No. 78
200
451
113
stone
2605
No. 7
183
600
gravel
2391
No. 78
150
508
56
stone
2410
Euclid
3/8''
Chemica
round
l
gravel or
Compan
limeston
y
160
600
e
2600
1997
172
400
2700
1991
167
300
2570
1993
167
300
2570
1994
167
300
2570
Table A.2. Examples of Field Projects of Pervious Concrete.

124

Fine
Aggreg
ate
(lb/yd3)

Fine
aggregate
(%)

A/C

W/C

28-day
Compressive
Strength
(psi)

170

7%

4.27

0.31

-

313

11%

6.47

0.44

-

170

7%

4.27

0.31

-

146

6%

5.03

0.30

-

0

0%
-

4.33
-

0.27
0.43
0.56
0.56
0.56

1970
1000
1000
1000
1000

-

APPENDIX B
PROPERTIES OF PERVIOUS CONCRETE COMPONENTS

125

Figure B.1. Properties of Coarse Aggregates

126

Figure B.2. Properties of Cement (St. Marys)

127

Continued
Figure B.3. Properties of High Range Water Reducer (Euclid Chemical Company)

128

Figure B.3. continued

129

Continued
Figure B.4. Properties of Mid-Range Water Reducer (Euclid Chemical Company)

130

Figure B.4. continued

131

Continued
Figure B.5. Properties of Mid-Range Water Reducer (Euclid Chemical Company)
Error! Reference source not found.. continued

132

133

Figure B.6. Properties of Viscosity Modifying Admixture (Euclid Chemical Company)

134

Continued
Figure B.7. Properties of Fiber (Euclid Chemical Company)

135

Figure B.7. continued

136

APPENDIX C
LABORATORY TEST RESULT (UNIT WEIGHT, VOID
CONTENT, UNCONFINED COMPRESSIVE STRENGTH,
PERMEABILITY)

137

Mix #1: AC46-FA00-WC27-5SD
Mixture Component
Cement, lb
Coarse Aggregate, SSD, lb
Fine Aggregate, SSD, lb
Water, lb
Poly fibers, 1#/cy
HRWR, oz/cwt.
Water Reducer, oz/cwt.
Viscosity oz/cwt.
Void
W/C Ratio
Total weight, lbs

Weight
7.01
30.34
1.67
1.88

Density/SG
3.15
2.63
2.61
1.00

4.43
1.86
2.06
41%
0.27
49.26

Total volume, ft3
Solids Volume, ft

Volume
0.04
0.18
0.01
0.03

0.44

3

0.26
3

Design Unit weight, lb/ft
Maximum Theoretical density,
lb/ft3
Table C.1. Mix Design of Pervious Concrete Mix #1

111.95
188.77

4in x 8in

Weight (lb)

Volume
(ft3)

Unit weight
(lb/ft3)

Void
Content

Sample (1)

6.6

0.058

112.8

40.2%

40.1%
Sample (2)
6.6
0.058
113.1
40.9%
Sample (3)
6.5
0.058
111.5
40.6%
Sample (4)
6.5
0.058
112.1
33.7%
Sample (5)
7.3
0.058
125.1
Table C.2. Unit Weight and Void Content of 4in x 8in Samples from Pervious
Concrete Mix #1
Note: compaction method: Rod-10/3 (rodding 10 times/layer, 3 layers )

138

Mix #2: AC46-FA30-WC22-5SD
Mixture Component
Cement, lb
Class F fly ash
Coarse Aggregate, SSD, lb
Fine Aggregate, SSD, lb
Water, lb
Poly fibers, 1#/cy
HRWR, oz/cwt.
Water Reducer, oz/cwt.
Viscosity oz/cwt.
Void
W/C Ratio
Total weight, lbs

Weight Density/SG
15.05
3.15
6.45
2.10
93.75
2.63
5.18
2.61
4.73
1.00
5.00
2.00
3.00

42%
0.22
135.16

Total volume, ft3

1.25

Solids Volume, ft3
Design Unit weight, lb/ft

Volume
0.08
0.05
0.57
0.03
0.08

0.73
3

108.13
3

Maximum Theoretical density, lb/ft
Table C.3. Mix Design of Pervious Concrete Mix #2

185.44

Volume
Unit weight
Void
3
3
4in x 8in
(ft )
(lb/ft )
content
Weight (lb)
6.1
0.058
105.2
43.3%
Sample (1)
6.2
0.058
106.7
42.5%
Sample (2)
6.2
0.058
105.8
43.0%
Sample (3)
6.2
0.058
106.5
42.6%
Sample (4)
6.2
0.058
106.2
42.7%
Sample (5)
6.1
0.058
105.2
43.3%
Sample (6)
6.2
0.058
106.8
42.4%
Sample (7)
6.2
0.058
107.3
42.2%
Sample (8)
6.2
0.058
106.1
42.8%
Sample (9)
6.2
0.058
106.7
42.5%
Sample (10)
6.1
0.058
105.6
43.1%
Sample (11)
6.2
0.058
106.0
42.8%
Sample (12)
Table C.4. Unit Weight and Void Content of 4in x 8in Samples from Pervious
Concrete Mix #2
Note: compaction method: Rod-10/3 (rodding 10 times/layer, 3 layers )
139

Mix #3: AC48-FA09-WC37-0SD
Mixture Component
Cement, lb
Class F fly ash
Coarse Aggregate, SSD, lb
Fine Aggregate, SSD, lb
Water, lb
Poly fibers, 1#/cy
Eucon WO, oz/cwt.
Eucon MRX, oz/cwt.
Visctrol oz/cwt.
Void
W/C Ratio
Total weight, lbs

Weight
29.40
2.80
152.99
0.00
11.79

Density/SG
3.15
2.10
2.63
2.61
1.00

Volume
0.15
0.02
0.93
0.00
0.19

6.00
12.00
1.00
26%
0.37
215.98

Total volume, ft3

1.74

Solids Volume, ft3

1.29
3

Design Unit weight, lb/ft
Maximum Theoretical density,
lb/ft3
Table C.5. Mix Design of Pervious Concrete Mix #3

124.27
167.15

Volume
Unit weight
Void
3
3
4in x 8in
Weight (lb)
(ft )
(lb/ft )
content
6.4
0.058
109.7
34.4%
Sample (1)
6.7
0.058
114.7
31.4%
Sample (2)
Table C.6. Unit Weight and Void Content of 4in x 8in Samples from Pervious
Concrete Mix #3
Note: this mix is from Buckeye Ready-mix Corp; compaction method: Jig-25/2 (jigging
25times/layer, 2 layers)

140

Mix #4: AC48-FA30-WC32-5SD
Mixture Component
Cement, lb
Fly Ash, lb
Coarse Aggregate, SSD, lb
Fine Aggregate, SSD, lb
Water, lb
Fiberstrand 100 (g)
PLASTOL 6200 EXT (g)
EUCON W.O, (g)
EUCON MRX, (g)
Visctrol oz/cwt. (g)
Void
W/C Ratio
Total weight, lbs
Total volume, ft

Weight
4.20
1.80
27.50
1.44
1.92
5.72
13.44
13.44
13.44
16.80

0.34

3

Design Unit weight, lb/ft

Volume
0.02
0.01
0.17
0.01
0.03
0.0002
0.0004
0.0004
0.0004
0.0005
27%
0.32

37.00

3

Solids Volume, ft

Density/SG
3.15
2.10
2.63
2.61
1.00
0.91
1.08
1.12
1.12
1.21

0.24
3

110.44

Maximum Theoretical density, lb/ft 3
Table C.7. Mix Design of Pervious Concrete Mix #4

151.42

Volume
Unit weight
Void
Weight (lb)
(ft3)
(lb/ft3)
content
6.991
0.058
120.2
20.6%
Sample (1)
6.398
0.058
110.0
27.4%
Sample (2)
6.372
0.058
109.5
27.7%
Sample (3)
6.648
0.058
114.3
24.5%
Sample (4)
Table C.8. Unit Weight and Void Content of 4in x 8in Samples from Pervious
Concrete Mix #4
Note: compaction method: Drop-10/3 (dropping with 2~3in height 5times/layer, 3
layers)

4in x 8in

141

Mix #5: AC43-FA02-WC34-5SD
Mixture Component
Cement, lb
Fly Ash, lb
Coarse Aggregate, SSD, lb
Fine Aggregate, SSD, lb
Water, lb
Fiberstrand 100 (g)
PLASTOL 6200 EXT (g)
EUCON W.O, (g)
EUCON MRX, (g)
Visctrol oz/cwt. (g)
Void
W/C Ratio
Total weight, lbs

Weight
26.40
0.50
109.14
5.74
9.00
20.18
55.90
56.30
55.50
69.40

1.15

3

Design Unit weight, lb/ft

Volume
0.13
0.00
0.67
0.04
0.14
0.0008
0.0019
0.0018
0.0018
0.0021
14%
0.34

151.35

Total volume, ft3
Solids Volume, ft

Density/SG
3.15
2.10
2.63
2.61
1.00
0.91
1.08
1.12
1.12
1.21

0.99
3

131.61
3

Maximum Theoretical density, lb/ft
Table C.9. Mix Design of Pervious Concrete Mix #5

152.74

Unit
Weight
Volume
Void
Compaction
weight
4in x 8in
(lb)
(ft3)
(lb/ft3)
content
Method
7.48
0.058
128.6
15.8%
Sample (1)
7.64
0.058
131.4
14.0%
Sample (2)
7.46
0.058
128.3
16.0%
Sample (3)
Drop-5/3
7.52
0.058
129.3
15.3%
Sample (4)
7.55
0.058
129.8
15.0%
Sample (5)
7.45
0.058
128.1
16.1%
Sample (6)
7.45
0.058
128.1
16.1%
Sample (7)
7.85
0.058
135.0
11.6%
Drop-10/3
Sample (8)
7.80
0.058
134.1
12.2%
Drop-15/3
Sample (9)
7.61
0.058
130.8
14.3%
Sample (10)
Proct-5/3
7.61
0.058
130.8
14.3%
Sample (11)
7.75
0.058
133.2
12.8%
Proct-10/3
Sample (12)
Table C.10. Unit Weight and Void Content of 4in x 8in Samples from Pervious
Concrete Mix #5
142

3in x 6in

Weight
(lb)

Volume
(ft3)

Unit
weight
(lb/ft3)

Void
content

Compaction
Method

3.09
0.025
125.9
17.6%
Sample (1)
3.02
0.025
123.0
19.4%
Sample (2)
Proct-5/3
3.11
0.025
126.7
17.0%
Sample (3)
3.15
0.025
128.3
16.0%
Sample (4)
3.19
0.025
130.0
14.9%
Proct-10/3
Sample (5)
Table C.11. Unit Weight and Void Content of 3in x 6in Samples from Pervious
Concrete Mix #5

Mix #6: AC45-FA32-WC34-5SD
Mixture Component
Cement, lb
Fly Ash, lb
Coarse Aggregate, SSD, lb
Fine Aggregate, SSD, lb
Water, lb
Fiberstrand 100 (g)
PLASTOL 6200 EXT (g)
EUCON W.O, (g)
EUCON MRX, (g)
Visctrol oz/cwt. (g)
Void
W/C Ratio
Total weight, lbs
Total volume, ft

Weight
16.22
7.65
103.40
5.20
8.11
20.18
52.47
52.47
52.47
65.59

18%

141.12

3

Solids Volume, ft

1.15

3

Design Unit weight, lb/ft

Density/SG Volume
3.15
0.08
2.10
0.06
2.63
0.63
2.61
0.03
1.00
0.13
0.91
0.0008
1.08
0.0017
1.12
0.0017
1.12
0.0017
1.21
0.0019

0.94
3

122.71
3

Maximum Theoretical density, lb/ft
Table C.12. Mix Design of Pervious Concrete Mix #6

143

150.01

Weight
Volume
Unit weight
Void
Compaction
3
3
(lb)
(ft )
(lb/ft )
content
Method
7.24
0.058
124.5
17.0%
Sample (1)
7.15
0.058
122.9
18.1%
Sample (2)
Proct-5/3
7.24
0.058
124.5
17.0%
Sample (3)
7.05
0.058
121.2
19.2%
Sample (4)
7.09
0.058
121.9
18.7%
Sample (5)
7.19
0.058
123.6
17.6%
Sample (6)
Drop-15/3
7.43
0.058
127.7
14.8%
Sample (7)
6.97
0.058
119.8
20.1%
Sample (8)
7.01
0.058
120.5
19.7%
Sample (9)
Drop-10/3
6.95
0.058
119.5
20.3%
Sample (10)
6.81
0.058
117.1
21.9%
Sample (11)
6.79
0.058
116.7
22.2%
Sample (12)
Drop-5/3
6.61
0.058
113.7
24.2%
Sample (13)
6.61
0.058
113.7
24.2%
Sample (14)
Table C.13. Unit Weight and Void Content of 4in x 8in Samples from Pervious
Concrete Mix #6

4in x 8in

Weight
Volume
Unit weight
Void
Compaction
3
3
3in x 6in
(lb)
(ft )
(lb/ft )
content
Method
2.68
0.025
109.2
27.2%
Sample (1)
Drop-5/3
2.76
0.025
112.4
25.0%
Sample (2)
2.91
0.025
118.6
21.0%
Sample (3)
Drop-10/3
2.89
0.025
117.7
21.5%
Sample (4)
3.10
0.025
126.3
15.8%
Proct-5/3
Sample (5)
Table C.14. Unit Weight and Void Content of 3in x 6in Samples from Pervious
Concrete Mix #6

144

Mix ID

Void
Content

#1 AC46-FA00-WC27-5SD

41%

#2 AC46-FA30-WC22-5SD

42%

#3 AC48-FA09-WC37-0SD

31%

#4 AC48-FA30-WC32-5SD

27%

#5 AC43-FA02-WC34-5SD

14%

#6 AC45-FA32-WC34-5SD

18%

Curing
Period
(days)
7
21
28
9
21
28
11

Compressive
Strength
(psi)
260.7
585.1
554.3
99.5
160.0
190.2
686.8

21
28
7
21
28
7
21
28
7
21
28

827.5
899.9
505.4
591.8
791.1
1947.7
2504.9
2705.0
1323.4
1413.0
1713.9

Table C.15. Compressive Strength of Specimens from Mix #1~#6 at 7, 21, and 28
Days Curing Periods

145

Mix ID
#1 AC46-FA00-WC27-5SD
#2 AC46-FA30-WC22-5SD
#3 AC48-FA09-WC37-0SD
#4 AC48-FA30-WC32-5SD

#5 AC43-FA02-WC34-5SD

#6 AC45-FA32-WC34-5SD

Unit
Weight
(lb/ft3)
111.5
106.7
114.7
109.5
128.3
129.3
135.0

Void
Content
41%
42%
31%
27%
16%
15%
12%

28-day
Compressive
Strength (psi)
554
190
900
791
2221
2258
3183

134.1
130.8
130.8
133.2
123.6
119.8
117.1
113.7
113.7

12%
14%
14%
13%
18%
20%
22%
24%
24%

3114
2206
1989
2705
1714
1432
1125
821
1296

Table C.16. 28-day Compressive Strength of Specimens from Mix #1~#6 with
Various Void Content

146

Mix #3: U=31%: 11-day curing period
800
700
600

Stress (psi)

500
400
Stress(psi)
300
200
100
0
0.0%

0.5%

1.0%

1.5%

2.0%

2.5%

3.0%

3.5%

Strain (%)

Figure C.1. 11-day Compressive Stress-strain Curve of Specimen with Void Contend
of 31% from Mix #3

Mix #3: U=31%: 21-day curing period
900
800
700

Stress (psi)

600
500
400

Stress(psi)

300
200
100
0
0.0%

0.5%

1.0%

1.5%

2.0%

2.5%

3.0%

3.5%

4.0%

4.5%

Strain (%)

Figure C.2. 21-day Compressive Stress-strain Curve of Specimen with Void Contend
of 31% from Mix #3

147

Mix #3: U=31%: 28-day curing period
1000
900
800

Stress (psi)

700
600
500
Stress(psi)
400
300
200
100
0
0.0%

0.5%

1.0%

1.5%

2.0%

2.5%

Strain (%)

Figure C.3. 28-day Compressive Stress-strain Curve of Specimen with Void Contend
of 31% from Mix #3
Mix #4: U= 27% 7-day curing period
600.

500.

Stress (psi)

400.

300.
Stress
200.

100.

0.
0.00%

0.50%

1.00%

1.50%

2.00%

2.50%

3.00%

3.50%

Strain (%)

Figure C.4. 7-day Compressive Stress-strain Curve of Specimen with Void Contend
of 27% from Mix #4

148

Mix #4: U= 27% 21-day curing period
700

600

Stress (psi)

500

400
Stress
300

200

100

0
0.0%

0.5%

1.0%

1.5%

2.0%

2.5%

3.0%

3.5%

4.0%

Strain (%)

Figure C.5. 21-day Compressive Stress-strain Curve of Specimen with Void Contend
of 27% from Mix #4
Mix #4: U= 27% 28-day curing period
900
800
700

Stress (psi)

600
500
Stress

400
300
200
100
0
0.0%

0.5%

1.0%

1.5%

2.0%

2.5%

3.0%

Strain (%)

Figure C.6. 28-day Compressive Stress-strain Curve of Specimen with Void Contend
of 27% from Mix #4

149

Mix #5: U= 12%: 7-days curing period
2000
1800
1600

Stress (psi)

1400
1200
Stress

1000
800
600
400
200
0
0.0%

0.5%

1.0%

1.5%

2.0%

2.5%

3.0%

3.5%

4.0%

Strain (%)

Figure C.7. 7-day Compressive Stress-strain Curve of Specimen with Void Contend
of 12% from Mix #5

Mix #5: U= 12%: 21-days curing period
3000

2500

Stress (psi)

2000

1500

Stress 21days(psi)

1000

500

0
0.0%

1.0%

2.0%

3.0%

4.0%

5.0%

6.0%

7.0%

Strain (%)

Figure C.8. 21-day Compressive Stress-strain Curve of Specimen with Void Contend
of 12% from Mix #5

150

Mix #5: U= 13%: 28-days curing period
3000

2500

Stress (psi)

2000

1500

Stress 28days(psi)

1000

500

0
0.0%

1.0%

2.0%

3.0%

4.0%

5.0%

6.0%

Strain (%)

Figure C.9. 28-day Compressive Stress-strain Curve of Specimen with Void Contend
of 13% from Mix #5

Mix #4: U= 27% 7-day curing period
1400
1200

Stress (psi)

1000
Stress

800
600
400
200
0
0.0%

1.0%

2.0%

3.0%

4.0%

5.0%

6.0%

7.0%

8.0%

Strain (%)

Figure C.10. 7-day Compressive Stress-strain Curve of Specimen with Void Contend
of 17% from Mix #6
151

Mix #6: U=18% 21-day curing period
1600
1400

Stress (psi)

1200
1000
Stress
21days(psi)

800
600
400
200
0
0.0%

0.5%

1.0%

1.5%

2.0%

2.5%

3.0%

3.5%

4.0%

Strain (%)

Figure C.11. 21-day Compressive Stress-strain Curve of Specimen with Void
Contend of 18% from Mix #6

Mix #6: U=18% 28-day curing period
2000

Stress (psi)

1500

1000
Stress
28days(psi)
500

0
0.0%

1.0%

2.0%

3.0%

4.0%

5.0%

6.0%

7.0%

Strain (%)

Figure C.12. 28-day Compressive Stress-strain Curve of Specimen with Void
Contend of 18% from Mix #6

152

28-day Stress vs. Strain Curve (U = 16%), Mix #5
2500
2000
1500
1000
500
0
0.0%

2.0%

4.0%

6.0%

Figure C.13. 28-day Compressive Stress-strain Curve of Specimen with Void
Contend of 16% from Mix #5

Compressive Stress (psi)

28-day Stress vs. Strain Curve (U = 15%), Mix #5
2500
2000
1500
1000
500
0
0.0%

2.0%

4.0%

6.0%

8.0%

Strain (%)

Figure C.14. 28-day Compressive Stress-strain Curve of Specimen with Void
Contend of 15% from Mix #5

153

28-day Stress vs. Strain Curve (U = 12%), Mix #5
Compressive Stress (psi)

3500
3000
2500
2000
1500
1000
500
0
0.0%

1.0%

2.0%

3.0%

Strain (%)

Figure C.15. 28-day Compressive Stress-strain Curve of Specimen with Void
Contend of 12% from Mix #5

Compressive Stress (psi)

28-day Stress vs. Strain Curve (U = 12%), Mix #5
3500
3000
2500
2000
1500
1000
500
0
0.0%

1.0%

2.0%

3.0%

4.0%

Strain (%)

Figure C.16. 28-day Compressive Stress-strain Curve of Specimen with Void
Contend of 12% from Mix #5

154

Compressive Stress (psi)

28-day Stress vs. Strain Curve (U = 14%), Mix #5
2500
2000
1500
1000
500
0
0.0%

2.0%

4.0%

6.0%

Strain (%)

Figure C.17. 28-day Compressive Stress-strain Curve of Specimen with Void
Contend of 14% from Mix #5

Compressive Stress (psi)

28-day Stress vs. Strain Curve (U = 14%), Mix #5
2500
2000
1500
1000
500
0
0.0%

2.0%

4.0%

6.0%

8.0%

Strain (%)

Figure C.18. 28-day Compressive Stress-strain Curve of Specimen with Void
Contend of 14% from Mix #5

155

Compressive Stress (psi)

28-day Stress vs. Strain Curve (U = 13%), Mix #5
3000
2500
2000
1500
1000
500
0
0.0%

2.0%

4.0%

6.0%

Strain (%)

Figure C.19. 28-day Compressive Stress-strain Curve of Specimen with Void
Contend of 13% from Mix #5

28-day Stress vs. Strain Curve (U = 18%), Mix #6

2000

Stress (psi)

1500
1000
500
0
0.0%

1.0%

2.0%

3.0%

4.0%

5.0%

6.0%

7.0%

Strain (%)

Figure C.20. 28-day Compressive Stress-strain Curve of Specimen with Void
Contend of 18% from Mix #6

156

28-day Stress vs. Strain Curve (U = 20%), Mix #6
2000

Stress (psi)

1500

1000

500

0
0.0%

1.0%

2.0%

3.0%

4.0%

Strain (%)

Figure C.21. 28-day Compressive Stress-strain Curve of Specimen with Void
Contend of 20% from Mix #6

28-day Stress vs. Strain Curve (U = 22%), Mix #6

Stress (psi)

1500
1000
500
0
0.0%

1.0%

2.0%

3.0%

4.0%

5.0%

Strain (%)

Figure C.22. 28-day Compressive Stress-strain Curve of Specimen with Void
Contend of 22% from Mix #6

157

28-day Stress vs. Strain Curve (U = 24%), Mix #6

Stress (psi)

1500

1000

500

0
0.0%

1.0%

2.0%

3.0%

4.0%

5.0%

Strain (%)

Figure C.23. 28-day Compressive Stress-strain Curve of Specimen with Void
Contend of 24% from Mix #6

28-day Stress vs. Strain Curve (U = 24%), Mix #6

Stress (psi)

1500

1000

500

0
0.0%

1.0%

2.0%

3.0%

4.0%

5.0%

6.0%

Strain (%)

Figure C.24. 28-day Compressive Stress-strain Curve of Specimen with Void
Contend of 24% from Mix #6

158

Measured
Calculated
Water
Permeability (Montes
Void
Permeability
(2006): ks = 18 *p3 /
Author
Contend
(cm/sec)
(1-p)2)
14.1
0.04
0.05
18.3
0.10
0.11
18.9
0.27
0.13
19
0.18
0.13
19
0.30
0.13
Wang, K.,
Schaelfer, V. R.,
20.2
0.24
0.15
Kevern, J. T., and
20.5
0.49
0.16
Suleiman, M. T
22.1
0.68
0.20
23
0.23
0.23
25.3
0.254
0.31
25.7
0.47
0.33
33.6
1.45
0.77
11
0.03
0.02
Kajio et al. 2003
15
0.18
0.06
15
0.20
0.06
Tennis et al. 2004
25
0.53
0.30
15.8
0.014
0.07
16.1
0.025
0.08
17.7
0.132
0.10
18.5
0.237
0.12
15.6
0.18
0.07
24.4
0.272
0.28
17.7
0.145
0.10
Montes, F., and
Haselbach,
22.4
0.154
0.21
L.(2006)
24.9
0.404
0.30
25.5
0.457
0.32
29.9
0.783
0.53
26.8
0.869
0.37
29.5
0.941
0.51
32
1.317
0.66
30.1
1.19
0.54
Continued
Table C.17. Measured and Calculated Permeability of Pervious Concrete
Specimens from Literature Review

159

Table C.17 continued
Crouch, L. K., et
al.

Suleiman, M. T

Crouch, L. K.,
Smith, N., Walker,
A. C., Dunn, T. R.,
and Sparkman, A.
(2006)

27.8
25.2
24.4
27.3
19
23.2
23
33.2
25.7
28.8
34.8
36.1
35.5
32.3
39.8
31.9
33.3
33.4
28.9
34.1
25.5
27.6
26.3
24.6
30.2
22.8
25.4
19.3
31.1
18.3
24.3
29.9
13.2
18.1
21.2
27.4

0.46
0.14
0.07
0.3
0.18
0.66
0.23
1.50
0.48
0.64
1.20
3.32
6.03
0.43
3.10
0.73
1.15
1.88
0.13
1.80
0.15
0.17
0.44
0.04
0.01
0.08
0.07
0.01
0.06
0.01
0.07
0.07
0.00
2.12
0.01
0.03

160

0.42
0.31
0.28
0.40
0.13
0.24
0.23
0.74
0.33
0.47
0.86
0.97
0.92
0.68
1.35
0.65
0.75
0.75
0.47
0.81
0.32
0.41
0.35
0.29
0.55
0.23
0.32
0.13
0.60
0.11
0.27
0.53
0.04
0.11
0.18
0.40

Falling head test
Height of top surface of water level:
Height of bottom surface of water level:
Difference height of water level:
a=
L=
A=
∆h0
∆h1 =

7.07
6.00
7.07
810.00
∆h0 - Q/A

in =
in =
in2 =
mm =

1220 mm
410 mm
810 mm
4560.37
152.40
4560.37
810.00

mm2
mm
mm2
mm

kS = 18 p3 / (1-p)2
k = (aL/At) * ln(∆h0/∆h1)
Table C.18. Permeability Calculation Parameters in Falling Head Permeability Test

161

Mix No.
Smaple No.

#5
2

Time (s)
4.48
3.26
5.29
5.52
6.15
6.78
4.54
5.36
6.2
5.91

Q (ml)
330
255
370
380
420
460
330
370
420
400

Testing date
Void content

3/13/2010
19.4%

k (in/hour)
451.2
473.9
431.0
424.8
423.9
423.7
445.2
425.3
420.5
418.9

k(cm/s)
0.32
0.33
0.30
0.30
0.30
0.30
0.31
0.30
0.30
0.30
0.30
0.20

∆h1 (mm)
738
754
729
727
718
709
738
729
718
722

ks =

Table C.19. Permeability Test Data for Specimen with Void Content of 19.5% from
Mix #5

Mix No.

#5

Smaple No.

1

Time (s)
6.4
5.33
7.4
8.45
7.2
7.98
7.61
4.99
9.54
10.61
8.92

Q (ml)
330
280
360
405
350
390
320
250
440
495
420

∆h1 (mm)
738
749
731
721
733
724
740
755
714
701
718

Testing date
Void
content

3/13/2010

k (in/hour)
315.8
319.5
299.3
296.9
298.6
302.0
257.2
303.3
287.2
292.9
292.3

k(cm/s)
0.22
0.23
0.21
0.21
0.21
0.21
0.18
0.21
0.20
0.21
0.21
0.21
0.14

ks =

17.6%

Table C.20. Permeability Test Data for Specimen with Void Content of 19.5% from
Mix #5

162

Mix No.
Smaple No.

#5
3

Time (s)
6.74
9.33
6.11
5.34
6.5
7.93
6.92
6.89
8.6
6.1

Q (ml)
295
405
270
240
290
340
310
310
380
275

Testing date
Void content

3/13/2010
17.0%

k (in/hour)
266.7
268.9
268.3
271.7
271.7
263.0
273.6
274.8
272.7
273.9

k(cm/s)
0.19
0.19
0.19
0.19
0.19
0.19
0.19
0.19
0.19
0.19
0.19
0.13

∆h1 (mm)
745
721
751
757
746
735
742
742
727
750

ks =

Table C.21. Permeability Test Data for Specimen with Void Content of 17.0% from
Mix #5

Mix No.
Smaple No.

#5
4

Time (s)
5.48
7.23
7.27
9.39
9.14
7.1
4.17
7.04
9.78
5.86

Q (ml)
240
305
310
390
380
300
190
290
400
260

Testing date
Void content

3/13/2010
16.0%

k (in/hour)
264.8
257.5
260.4
256.7
256.5
257.7
273.5
250.9
253.1
269.0

k(cm/s)
0.19
0.18
0.18
0.18
0.18
0.18
0.19
0.18
0.18
0.19
0.18
0.10

∆h1 (mm)
757
743
742
724
727
744
768
746
722
753

ks =

Table C.22. Permeability Test Data for Specimen with Void Content of 16.0% from
Mix #5

163

Mix No.

#5

Smaple No.

5

Time (s)
8.71
8.22
6.46
8.93
14.48
11.34
12.24
4.16
4.98
10.5
9.45

Q (ml)
250
265
210
280
430
350
380
130
180
310
338

∆h1 (mm)
755
752
764
749
716
733
727
781
771
742
736

Casting date
Void
content

2/26/2010

k (in/hour)
173.8
188.5
190.1
183.3
173.6
180.5
181.5
182.7
211.4
172.6
209.1

k(cm/s)
0.12
0.14
0.14
0.13
0.13
0.13
0.14
0.13
0.15
0.13
0.15
0.13
0.08

ks =

14.9%

Table C.23. Permeability Test Data for Specimen with Void Content of 14.9% from
Mix #5

Mix No.
Smaple No.

#6
1

Time (s)
2.83
2.86
3.78
4.98
1.93
3.05
3.92
2.61
3.36
2.2
3.17

Q (ml)
370
340
430
545
280
350
440
300
375
270
360

∆h1 (mm)
729
735
716
690
749
733
714
744
728
751
731

Testing date
Void content

4/19/2010
27.2%

k (in/hour)
805.6
729.3
707.2
692.4
882.2
705.0
698.9
701.0
688.2
745.2
698.7

k(cm/s)
0.57
0.51
0.50
0.49
0.62
0.50
0.49
0.49
0.49
0.53
0.49
0.50
0.69

ks =

Table C.24. Permeability Test Data for Specimen with Void Content of 27.2% from
Mix #6

164

Mix No.
Smaple No.

#6
2

Time (s)
3.28
3.17
3.21
3.27
4.69
4.2
5.61
4.17
3.98
4.63
3.62

Q (ml)
320
375
325
380
510
450
580
425
360
395
330

∆h1 (mm)
740
728
739
727
698
711
683
717
731
723
738

Testing date
Void content

4/19/2010
25.0%

k (in/hour)
596.7
729.4
619.7
717.1
684.3
668.1
657.7
633.1
556.5
527.6
558.4

k(cm/s)
0.42
0.51
0.44
0.51
0.48
0.47
0.46
0.45
0.39
0.37
0.39
0.45
0.50

ks =

Table C.25. Permeability Test Data for Specimen with Void Content of 25.0% from
Mix #6

Mix No.

#6

Smaple No.

3

Time (s)
2.35
3.01
2.78
3.23
4.79
3.83
3.46
3.08
4.45
4.04

Q (ml)
225
240
220
255
365
300
270
240
332
310

Testing
date
Void
content
∆h1 (mm)
761
757
762
754
730
744
751
757
737
742

k (in/hour)
577.6
482.1
477.1
478.4
469.2
477.7
473.8
471.1
457.1
468.6
ks =

4/19/2010
21.0%
k(cm/s)
0.41
0.34
0.34
0.34
0.33
0.34
0.33
0.33
0.32
0.33
0.34
0.27

Table C.26. Permeability Test Data for Specimen with Void Content of 21.0% from
Mix #6
165

Mix No.
Smaple No.

#6
4

Time (s)
3.41
3.05
3.16
4.05
3.21
3.69
3.72
3.22
3.08
3.45

Q (ml)
270
255
320
325
205
310
330
260
200
286

∆h1 (mm)
751
754
740
739
765
742
738
753
766
747

Testing date
Void content

4/19/2010
21.5%

k (in/hour)
480.8
506.6
619.4
491.2
384.2
513.1
543.4
489.6
390.4
504.5

k(cm/s)
0.34
0.36
0.44
0.35
0.27
0.36
0.38
0.35
0.28
0.36
0.35
0.29

ks =

Table C.27. Permeability Test Data for Specimen with Void Content of 21.5% from
Mix #6

Mix No.

#6

Smaple No.

5

Time (s)
4.6
4.01
4.33
6.86
1.87
3.8
9.84
9.56
4.04
4.73

Q (ml)
300
200
210
315
110
190
430
420
200
220

∆h1 (mm)
744
766
764
741
786
768
716
718
766
762

Testing date
Void
content

4/19/2010

k (in/hour)
397.7
299.8
292.0
280.7
349.2
300.2
271.7
272.7
297.6
280.4

k(cm/s)
0.28
0.21
0.21
0.20
0.25
0.21
0.19
0.19
0.21
0.20
0.21
0.10

ks =

15.8%

Table C.28. Permeability Test Data for Specimen with Void Content of 15.8% from
Mix #6

166

Void content vs. compaction methods on all samples
Compaction
Method

Rod-10/3

Proct-5/3

Mix ID

Void Content

#1 AC46-FA00-WC27-5SD
#2 AC46-FA30-WC22-5SD
#5 AC43-FA02-WC34-5SD

41%
42%
14%
17%
18%
17%
19%
19%
14%
16%
15%
15%
16%
16%
22%
22%
27%
12%
20%
20%
20%
12%
18%
15%

#6 AC45-FA32-WC34-5SD

#5 AC43-FA02-WC34-5SD
Drop-5/3

#6 AC45-FA32-WC34-5SD
#4 AC48-FA30-WC32-5SD
#5 AC43-FA02-WC34-5SD
Drop-10/3
#6 AC45-FA32-WC34-5SD
#5 AC43-FA02-WC34-5SD
Drop-15/3

#6 AC45-FA32-WC34-5SD

Average
Void
Content

41%
42%
14%

18%

15%

22%
27%
12%
20%
12%
16%

Table C.29. Void Contents of Specimens Compacted at Different Compaction
Methods

167

APPENDIX D
PERVIOUS CONCRETE MIX DESIGN PROGRAM CODE
using
using
using
using
using
using
using
using

System;
System.Collections.Generic;
System.ComponentModel;
System.Data;
System.Drawing;
System.Linq;
System.Text;
System.Windows.Forms;

namespace concrete_mix_design
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
double Cementitious, HRWR_cwt, WR_cwt, Viscosity_cwt, A_C, W_C, Volume;
double CASG, SandSG, FASG, CementSG;
double Cement, FA, TA, CA,Sand, Water, HRWR, WR, Viscosity, FApercent;
double Cement_f, FA_f, CA_f, Sand_f, Water_f;
double CAVol, SandVol, FAVol, CementVol, WaterVol, ARVol, SolVol, SolW;
double AR, UnitW, UnitW_f, UnitW_Max, UnitW_Max_f;
double MoldW, SamplW,SamplWMax, MandSampl, MandSamplMax;
string output = " ";
private void button1_Click(object sender, EventArgs e)
{
Cementitious = Convert.ToDouble(textBox_cement.Text);
HRWR_cwt = Convert.ToDouble(textBox_HRWR.Text);
WR_cwt = Convert.ToDouble(textBox_WR.Text);
Viscosity_cwt = Convert.ToDouble(textBox_Viscosity.Text);
A_C = Convert.ToDouble(textBox_A_C.Text);
W_C = Convert.ToDouble(textBox_W_C.Text);
FApercent = Convert.ToDouble(textBox_FApercent.Text);
CASG = Convert.ToDouble(textBox_CASG.Text);

168

SandSG = Convert.ToDouble(textBox_SandSG.Text);
FASG = Convert.ToDouble(textBox_FASG.Text);
CementSG = Convert.ToDouble(textBox_CementSG.Text);
Volume = Convert.ToDouble(textBox_Volume.Text);

HRWR = HRWR_cwt * Cementitious *28.35*Volume/ 100;
WR = WR_cwt * Cementitious *28.35*Volume/ 100;
Viscosity = Viscosity_cwt * Cementitious*28.35*Volume/ 100;
HRWR = Math .Round (HRWR ,2);
WR = Math .Round (WR,2);
Viscosity = Math .Round (Viscosity ,2);
label_HRWR.Text = output + HRWR;
label_WR.Text = output + WR;
label_Viscosity.Text = output + Viscosity;

FA = Cementitious * FApercent /100;
Cement = Cementitious *(100-FApercent)/100;

TA = Cementitious * A_C;
Sand = TA * 0.05;
CA = TA * 0.95;
//Water = W_C * Cementitious - CA * Moisture / 100;
Water = W_C * Cementitious;
//CA = CA + CA * Moisture / 100;
SolW = CA + Sand + Cementitious + Water + HRWR/453.6 +WR/453.6 +Viscosity/453.6 ;
CAVol = CA / CASG / 62.4;
SandVol = Sand / SandSG / 62.4;
FAVol = FA / FASG / 62.4;
CementVol = Cement / CementSG / 62.4;
WaterVol = Water / 62.4;
SolVol = CAVol + SandVol + FAVol + CementVol + WaterVol;
ARVol = Volume - SolVol;

AR = ARVol*100/Volume;
UnitW = SolW;
UnitW_Max = SolW / SolVol;
AR = Math.Round(AR, 1);
label_VR.Text = output + AR;
}
private void comboBox_Unit_SelectedIndexChanged_1(object sender, EventArgs e)
{
if (comboBox_Unit.Text == "lb")
{

169

CA_f = CA;
Sand_f = Sand;
Cement_f = Cement;
FA_f = FA;
Water_f = Water;
}
else if (comboBox_Unit.Text == "g")
{
CA_f = CA * 453.6;
Sand_f = Sand * 453.6;
Cement_f = Cement * 453.6;
FA_f = FA * 453.6;
Water_f = Water * 453.6;
}
CA_f = Math.Round(CA_f, 1);
Cement_f = Math.Round(Cement_f, 1);
Sand_f = Math.Round(Sand_f, 1);
FA_f = Math.Round(FA_f, 1);
Water_f = Math.Round(Water_f, 1);

label_Cement.Text = output + Cement_f;
label1_CA.Text = output + CA_f;
label1_Sand.Text = output + Sand_f;
label_FA.Text = output + FA_f;
label1_water.Text = output + Water_f;
}
private void comboBox_Unit2_SelectedIndexChanged(object sender, EventArgs e)
{
if (comboBox_Unit2.Text == "lb/ft3")
{
UnitW_f = UnitW;
UnitW_Max_f = UnitW_Max;
}
else if (comboBox_Unit2.Text == "kN/m3")
{
UnitW_f = UnitW / 6.37;
UnitW_Max_f = UnitW_Max / 6.37;
}
UnitW_f = Math.Round(UnitW_f, 1);
UnitW_Max_f = Math.Round(UnitW_Max_f, 1);
SolVol = Math.Round(SolVol, 1);

label_UnitW.Text = output + UnitW_f;
label_UnitW_Max.Text = output + UnitW_Max_f;
label_SolidVol.Text = output + SolVol;

170

}
private void button2_Click(object sender, EventArgs e)
{
MoldW = Convert.ToDouble(textBox_Mold.Text);
if (comboBox_Mold.Text == "3 x 6 in")
{
SamplW = 453.6 * UnitW_f * Math.PI * 9 * 6 / 4/12/12/12;
SamplWMax = 453.6 * UnitW_Max_f * Math.PI * 9 * 6 / 4 / 12 / 12 / 12;
}
if (comboBox_Mold.Text == "4 x 8 in")
{
SamplW = 453.6 * UnitW_f * Math.PI * 16 * 8 / 4 / 12 / 12 / 12;
SamplWMax = 453.6 * UnitW_Max_f * Math.PI * 16 * 8 / 4 / 12 / 12 / 12;
}
if (comboBox_Mold.Text == "4 x 4 x 16 in")
{
SamplW = 453.6 * UnitW_f * 4 * 4 * 16 / 12 / 12 / 12;
SamplWMax = 453.6 * UnitW_Max_f * 4 * 4 * 16 / 12 / 12 / 12;
}
MandSampl = MoldW + SamplW;
MandSamplMax = MoldW + SamplWMax;
MandSampl = Math.Round(MandSampl, 1);
MandSamplMax = Math.Round(MandSamplMax, 1);
label_SamplW.Text = output + MandSampl;
label_SamplMW.Text = output + MandSamplMax;
}
}
}

171