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For the building contractor, time and costs are decisive factors in the economic success or failure of a construction project. To carry out various jobs most efficiently, contractors make use of specially selected construction machines which operate both quickly and economically. Manufacturers brochures and special handbooks are available to assist the contractor in selecting equipment and calculating costs. Construction machinery at the site represents a considerable capital investment. The costs of loss or damage due to unforeseen events cannot be calculated in advance by the contractor, since neither brochures nor cost calculation handbooks can provide the required information. The contractor can, however, insure his machinery against the consequences

Perils of Construction Machinery
In general, the causes of damages to construction machinery can be divided into three categories :  Acts of God ( natural hazards )  Operating Errors  Material Failure Acts of God are unforeseeable. Typical Acts of God are flood, inundation, storm, earthquake, rockslide, landslide, lightning. An expanded definition could also include other events over which the policyholder has little influence, such

Perils of Construction Machinery…..
Damage resulting from operator error and human negligence can in principle be reduced by adequate training of personnel. For the Contractor, however, employee error is unforeseeable, so that property damage resulting from such causes is covered by construction machinery insurance. Typical examples here are collision of vehicles on the construction site and tipping of cranes. Theft or vandalism can also be included in this category. The age and condition of a machine, as well as the regular maintenance, all effect the probability of loss occurrence. Material failure,

Insurance of Construction Machinery

General
• Construction machinery insurance protects contractors against losses which he cannot calculate in advance. The intent is to reimburse him for losses resulting from a direct, sudden and unforeseen external event.. • Construction machines are not as a rule utilized at a single construction site for the entire duration of their service life. Once work is completed, or as otherwise required, the machinery is transported to other sited for further use. • In order to deal with this situation and the special needs of the policyholder, two policy

Types of Insurance
• Insurance for a Project
– Under this type of scheme the machinery is insured within the scope of a CAR / EAR policy for a specific project. During its utilization at this particular site, the equipment is insured. This type of insurance is suitable primarily for long-term projects and for construction sites where several contractors contribute machinery for the project. This policy has the advantage of uniform insurance coverage for all machinery used on the site, and the insurance premium can be shared by all participating contractors. Insurance of this type is for a specific location and a predetermined policy duration

• Annual Policy
– A contractor’s entire fleet of machines can be insured with an annual policy. This type of insurance covers all machinery, regardless of the location of the construction sites. An annual policy is the most suitable type of insurance if the contractor is working at several smaller

Insured Property
• In both forms of insurance stationary and mobile machinery of all types may be insured. Floating equipment and equipment registered for general road use, should not be insured as construction machinery. • As a rule, all the machinery utilized at a construction site or the whole machinery fleet of a contractor should be insured. All the machines insured must be included in a machinery

Insured Perils
• Comprehensive coverage is provided for in construction machinery insurance ie all damages are covered resulting from hazards which are not specifically excluded • The most important exclusion is machinery breakdown, which regardless of the cause (operational influences, wear, deficiency of water, oil or lubricant), should not be covered. Damage as a consequence of such machinery breakdown is, however, covered. Further exclusions are the consequences of war, strike, riot, nuclear reaction, willful negligence on the part of the insured, design defects for which the manufacturer is contractually liable and consequential losses. • As an exception to this general rule it is, in some countries, possible to insure against

Sum Insured
• The sum insured must be based on the new replacement value including freight, customs duties and assembly costs. Changes in the agreed value during the course of the policy period ie changes due to inflation, must be compensated for by continuous adjustment of the sum insured. • The current value ie the price which would be realized if the machine were sold on the open market, may

Scope of Compensation
• The purpose of construction machinery insurance is to reimburse the policyholder the losses resulting from unforeseeable events. In the case of total loss (repair costs higher than the current value), the insurer reimburses at current market value. • In the case of a partial loss (repair costs lower than the current value) the insurer reimburses the cost of the required replacement parts and the lobour costs for repairing the machine, without deducting for wear and age ( the exception being the parts which must be replaced regularly several times during the service of a machine ) • Since construction machinery insurance is a

Deductibles
• The claims history in construction machinery insurance is influenced by a number of factors, amongst which are training of the personnel, the age, condition and utilization of the machines as well as the organisation of construction site operations. Since all these factors are within the policyholder’s control, he has certain influence on the loss frequency. In order to encourage the policyholder to prevent losses, he is requested to participate with a percentage of each claim. • Minor losses which occur at intervals due to the nature of operations often involve administrative costs, both for insurer and

Characteristic Data
• Maximum New Values are applicable to large standard units and are based on prices of 1979. Actual values may be calculated by applying indices. • Rates of Depreciation and Interest may assist determining the approximate book value for equipment, when dealing with used machinery or in the case of a loss. 10% was taken as the interest rate for purposes of calculation. The book value does not necessarily correspond to the current market

Characteristic Data……
• The Repair Cost Rates represent the monthly amount which a contractor must on average spend for regular maintenance and repair (replacement parts and labour costs ). • The Hazard Class is intended to give the insurer a feeling for the degree of risk to which a certain unit is exposed in normal operations. The degree of hazard is divided into four risk categories : • A = Low • B = Low – Medium

Material Preparation • Solid aggregate for concrete must be available in grains of graduated size. Coarsely broken rock is crushed further in several steps. Coarse crushing is with ‘brute force’ in crushers (jaw-type crushers, gyratory crushers, hammer crushers) with subsequent size reduction in mills, down to the size of sand grains. Between the individual reduction steps the material is washed and stored according to grain size: Coarse grain are classified with stationary or vibrating sieves; water is added to fine grains, which are then separated by size in classification tanks, cyclones or slurry separators. • The size reduction and grading machines are often located in a single building, either one

Material Preparation • PARAMETER : • Engine Power : • Weight : • Carrying Capacity : • Load Moment : • Throughput : to 850 t/h • Nominal Fill : • Max. New Value : 500,000 • Service Life : • Depreciation and Interest per month • Repair Cost :

Crushers up

US$ 10 Years : 1.3% 0.7% per

Material Preparation

• Processing systems such as these are subject to extremely hard operating conditions and high wear rates, resulting in correspondingly high repair costs. Bearings and suspension elements are subject to extreme mechanical forces; the moist atmosphere results in corrosion. Varying size and harness of the rock can lead to interruption in operations; deposits and clogging can cause damage with very fine grain sand. • The systems are exposed to acts of God such as earthquake, flooding

Manufacturing Concrete
• Cement, aggregate and water must be mixed to manufacture concrete. Systems for concrete mixing range from a bucket and shovel to large-scale plants in which the aggregates and cement are stored in silos and conveyed to the metering station by conveyor belts, vibration troughs or pneumatic pumps. In smaller systems feed is from open storage (star stockpiles) using a cable-drawn bucket. • At the metering station the aggregates and cement are weighed, water added and fed to the mixer. Various types of mixers are used, depending on the required throughput capacity. • Automatic concrete mixer plants usually exhibit a tower-like configuration and are

Manufacturing Concrete
• PARAMETER : • Engine Power : • Weight : • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : • Max. New Value : • Service Life : • Depreciation and Interest per month • Repair Cost : month • Hazard Class : A

6 Years : 1.8% 1.1% per

Manufacturing Concrete

• Being a part of site equipment, concrete mixing plants are exposed primarily to external perils. The location of the plant must be inspected in respect of flooding, rockslides etc. Due to the high level of wear and tear and the extreme dependency on maintenance and care, machinery breakdown should be included

Tower Cranes
• Rotary Tower Cranes are used in highrise construction for vertical transportation of all types of loads. Stationary cranes, mounted on foundations, can cover only a limited radius and are therefore often used in groups on large construction sites. Cranes mounted on undercarriage, travelling on rails, are more mobile and more economical for sites which have one long axis, while smaller cranes often operate on tyres or crawler-type chassis. • The height of mobile cranes can be regulated by adding inserts; stationary cranes may be equipped with climbing features, usually hydraulic, with which the crane can ‘grow’ with the structure. • A special type of stationary rotary tower

Tower Cranes
• PARAMETER : • Engine Power : • Weight : • Carrying Capacity : • Load Moment : 1250 tm • Throughput : • Nominal Fill : • Max. New Value : US$ 1.2 M • Service Life : 8 Years • Depreciation and Interest : 1.5% per month • Repair Cost : 0.7% per month • Hazard Class : D

Tower Cranes
• Due to their geometry, the hazard of tipping is high for rotary tower cranes. The factors which may trigger a fall are overloading, yielding of the foundation, negligent laying of the tracks or wind load. Carelessness and negligence result in operational hazard : overload kickouts and limit switches are disconnected, the cranes collide with the track bumpers and tip, track clamps are used incorrectly. With increasing age hoist and holding ropes wear, connecting components encounter

Special Cranes
• Due to their limited range of movement rotary tower cranes are unsuitable to certain construction projects and tasks. For this reason special type of cranes have been developed which are adapted to the particular job to be handled. Sites with one long axis, such as in dam construction, are served by cable cranes. A crab, carrying the load hook, moves along a steel cable which spans the site. In order to allow for lateral movement as well, the support points for the carrying cable can be shifted correspondingly. In other cases the cable is attached to guyed lattice masts which can be tilted to the side. • Facilities with larger surface areas, such

Special Cranes…..
• Typical characteristics of special design cranes are exceptional carrying capacity, span width, mobility or other parameters. Hereby new values and service lives vary. Therefore it is not possible to make general statements.

Special Cranes…..
• Main hazards are acts of God, such as earthquake, storm and flooding, as well as rock and landslide. Loose guy wires and frayed cables can be detected during regular inspections and subsequently corrected. Consequential losses usually result from serious crane damage. • Individual design and application make for widely varying risk characteristics, which must be examined and evaluated from case to case. In addition to the influence of external dangers, the experience

Telescopic Truck Cranes
• Telescopic truck cranes are mobile lifting units which are not usually assigned continuously to one construction site, but which are moved from site to site as required. The undercarriage is, or corresponds to, a heavy duty lorry chassis, on which the telescopic boom is mounted in a slewable configuration. Upon arrival at the construction site a location suitable for the lifting assignment is selected. Stabilization is created with hydraulic outriggers extending at sides. The lift height is achieved by extending the telescopic boom hydraulically.

Telescopic Truck Cranes
• PARAMETER : • Engine Power : • Weight : • Carrying Capacity : • Load Moment : 900 • Throughput : • Nominal Fill : • Max. New Value : M • Service Life : • Depreciation and Interest 1.8% per month • Repair Cost :

225 t tm

US$ 1.0 6 Years : 1.0%

Telescopic Truck Cranes
• Changing locations, difficult lifting assignments and high rental charges can lead toChanging locations, difficult lifting assignments and high rental charges can lead to hectic operations in which insufficient attention is paid to stability and safety. Overload kickouts can be neutralized, which can lead tots can be neutralized, which can lead to tipping • Telescopic truck cranes represent a difficult rint a difficult risk from the insurer’s point of view. Losses caused by neutralizing the overload kickout shoud be excluded by endorsement. Extremely high risk in cases of simultaneous use of several truck cranes for a lift; therefore control equipment must be prescribed for

Lattice Mast Truck Crane
• Truck cranes with lattice mast booms are the typical lifting equipment found on erection sites since they are highly mobile and can handle even extremely heavy loads. A slewable crane is mounted on a heavy lorry chassis; the load is suspended on a steel cable. The boom can be extended with inserts. The method of slewing and of vertical boom movement is mechanical or hydraulic. In addition to continuous use on a large construction site, lattice mast truck cranes are used intermittently for special jobs at smaller sites. • Large and bulky objects, such as components for offshore drd

Lattice Mast Truck Crane
• PARAMETER : • Engine Power : • Weight : 80 Mp • Carrying Capacity : 360 t • Load Moment : 2200 tm • Throughput : • Nominal Fill : • Max. New Value : US$ 1.1 M • Service Life : 8 Years • Depreciation and Interest : 1.5% per month • Repair Cost : 0.9% per month •

Lattice Mast Truck Crane
• In addition to the ground stability, which differs according to location, the major problem encountered with truck cranes is the object to be lifted, the weight of which is often not known exactly. Switching off the overload kickout can result in overloading, and in turn to be lifted, the weight of which is often not known exactly. Switching off the overload kickout can result in overloading, and in turn to the cranes tipping over. Several cranes lifting in unison is particularly

Forklift Truck
• Forklift trucks are used primarily in storage facilities for lifting and transport requirements. Their specialty is loading and unloading vehicles and stacking goods. They have forks at the front, which can be raised and lowered with a chain drive. Rear axle steering makes for extreme maneuverability. The forklift may be powered by internal combustion engines, by a dieselelectril-electric configuration, or battery. Rough terrain forklift trucks are used for site work and

Forklift Truck
• PARAMETER : • Engine Power : • Weight : • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : • Max. New Value : • Service Life : • Depreciation and Interest per month • Repair Cost : month

5t

US$ 50,000 8 Years : 1.5% 0.9% per

Forklift Truck
• In case of overloading or when travelling over uneven surfaces forklift trucks have a tendency to uneven surfaces forklift trucks have a tendency to tip to the front. The danger of damage to the unit by a falling load must be taken into consideration. • In general a relatively low-risk item, since the truck can be evacuated in case of danger

Transportation Equipment

Lorries
• Material transportation at construction sites is generally effected by lorries, which will differ according to their dumping mechanism. The smallest units are the dumpers, which are built for payloads of up to 5 tons and are generally equipped with fourwheel drive and center-pivot steering. Rear or side dump trucks up to 20 tons payloads are used for transporting sand, gravel etc. Coarse material is transported in off-highway haulers, the capacity of which can be up to 200 tons. The type of drive used for the wheels will differ according to the various models.

• PARAMETER : • Engine Power : • Weight : • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : • Max. New Value : • Service Life : • Depreciation and Interest per month • Repair Cost : month • Hazard Class : C

200 t

US$ 1.6 m 4 Years : 2.5% 2.0% per

• Large off-highway haulers are highly exposed to perils at earthmoving sites, since they are often driven fast and close together (collision danger). Particularly during unfavourable weather conditions the danger of skidding off the road is high. Road ways must therefore be constantly maintained by graders. • The insurance risk depends on the nature of the transportation route and on the training and experience

Low-bed Trailers
• Crawler-type equipment is moved from one jobsite to the next with low-bed trailers, which can also be used to transport heavy, prefabricated components, transformers, etc. The larger models are usually constructed as semitrailers and may run on as many as 36 wheels. Considerably larger models are

• PARAMETER : • Engine Power : • Weight : • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : • Max. New Value : • Service Life : • Depreciation and Interest per month • Repair Cost : month • Hazard Class : B

40 t

US$ 70,000 8 Years : 1.5% 1.3% per

• A ramp can be used for loading and unloading self-propelled vehicles (bulldozers, excavators, etc) on and off the low-bed trailer; otherwise a crane may be used. • Relatively low risk. Major risks are AOG and leaving the roadway.

Mixer Lorries
• When pouring small volumes of concrete or on construction sites where space does not allow the installation of a concrete mixing unit, concrete can be brought to the site from an outside source. A mixer is mounted on a lorry chassis and rotates during the drive to the site, mixing the concrete. Normally, the ready-mix concrete is discharged trough a chute into a bucket, which is then moved by a crane. Instead of a bucket and crane, concrete pumps may be

• PARAMETER : • Engine Power : • Weight : • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : • Max. New Value : • Service Life : • Depreciation and Interest per month • Repair Cost : month •

10 M3 US$ 50,000 6Years : 1.8% 1.1% per

• If there are delays, for example due to heavy traffic, the concrete may set in the mixer. • Low insurance risk, with the normal hazards on public roads and construction sites.

Transportation on Rails
• Due to the great amount of time involved in laying the rails, transportation equipment running on rails is used only on construction projects of several year’s duration. The gauges are as a rule 600 mm, 900 mm or standard gauge (1,435 mm) and drive is either by diesel engine or battery power ( for tunnel construction) Single-

• PARAMETER : • Engine Power : 120 kW • Weight : 22 Mp • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : • Max. New Value : US$ 220,000 • Service Life : 10 Years • Depreciation and Interest : 1.3% per month • Repair Cost : 0.8% per month • Hazard Class : A, tunnel

• With the danger of cave-ins and flooding, the rail systems in tunnel construction or exposed to considerably greater perils than those installed in the open. The position and condition of the rails must be inspected regularly in order to reduce the risk of derailing

Conveyor Belts
• Conveyor belts allow continuous material transportation in quarrying gravel and mining raw materials as well as when constructing dams. The endless belts are driven and supported by rollers, the overall length is often divided into segments to reduce starting inertia. Conveyor belts are assembled from individual segments, including the drive and tensioning stations, the roll way, the rubber belt and a stripper. The efficiency and economy of transportation is determined by the width and running speed of the belt. • In addition to land-based conveyor belts there are also belt systems which float on pontoons, designed for use with dredgers.

• PARAMETER : • Engine Power : • Weight : • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : 3m • Max. New Value : per M • Service Life : • Depreciation and Interest per month • Repair Cost : month

Width upto US$ 1,000 – 7 Years : 1.6% 0.7% per

• While belts themselves are subjected to greatest wear where the material is loaded onto the belt, the rollers are subjected to extreme wear when handling coarse material (rock). Operational interruptions will be frequent when handling sticky material (clay, loam). Flooding should be mentioned as a particular hazard. The belt itself is a

Transport by Pipeline
• Liquids or slurries of solids and water are commonly transported by pipeline. Typical application areas for pipeline transport are in lowering the water table, whereby the ground water which is extracted must often be pumped over great distances to a disposal point; or suction dredging operations in which a mixture of water and soil is trasported; or transporting concrete through pipelines. There is a distinction between suction and pressure pumps on the basis of their location. The pumping capacity required is dependent on the height differential, the composition of the slurry and coefficients of friction. Either

• PARAMETER : • Engine Power : • Weight : • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : • Max. New Value : 60,000 • Service Life : • Depreciation and Interest per month • Repair Cost : month

Pumps US$ 7 Years : 1.6% 1.1% per

• Pumps for slurries of solids and water are subject to extreme wear due to abrasion. Underwater pumps are by nature difficult to inspect and correspondingly high breakdown rates. • If machinery breakdown is excluded, pumps represents low insurance risks, since they are usually in stationary

Digging
and

Loading

Bulldozers
• The bulldozers blade which is mounted at the front can be raised and lowered hydraulically. Bulldozers remove soil material, push it to the dumping area and spread it out. The unit is powered by an air- or water-cooled engine. For heavy material, dozers on crawler tracks are used; in lighter material rubber-tyred models may be used, which have greater mobility. Crawler dozers are also used on large earthworks as pushers for scrapers, as towing

• PARAMETER : • Engine Power : 550 kW • Weight : 80 Mp • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : • Max. New Value : US$ 700,000 • Service Life : 4 Years • Depreciation and Interest : 2.5% per month • Repair Cost : 2.1% per month • Hazard Class : C

• Bulldozers are used primarily for heavy earth-moving work. There is a high degree of abrasion at the tracks and the shanks of the rearmounted ripper. Heavy loading of gearing and hydraulic systems are common. Machinery breakdown should not be covered and all parts subject to wear should be excluded. The danger of slides and falls in mountainous terrain and of bogging down in swampy ground should be taken into consideration. Just as with other machinery it is

Scrapers
• Scrapers are rubber-tyred combined loading and transport units. The scarper is filled by lowering the bowl into the ground while the unit travels forwards, thus cutting the material and collecting it. Since great power is required for this operation, a crawler dozer is often used as an aid to push the scarper. • A towed scraper is pulled by a bulldozer, the motor-scraper is self-propelled and may be equipped with one or two engines. To facilitate the loading procedure the elevator scraper is equipped with a conveyor covering the entire width of the bowl. The bowl is also emptied while in motion, with an ejector

• PARAMETER : • Engine Power : 700kW • Weight : • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : 30 m3 • Max. New Value : US$ 700,000 • Service Life : 4 Years • Depreciation and Interest : 2.5% per month • Repair Cost : 1.9% per month • Hazard Class : C

• The economics of the scraper depend upon the speed during loading and transport.. When operating on roadways which are inadequately maintained, the risks of collision and tipping play a major role. Risk during operation depends mainly on the training and experience of the operator and the nature of the haul road, which must be continuously maintained by grades, particularly during bad

Loaders
• Wheeled and crawler loaders are equipped with hydraulically controlled front loading buckets and are particularly well suited for loading vehicles with material. The wheeled loaders, if provided with center-pivot steering, are fast highly maneuverable, and are used primarily for shovel-like pickup of loosely piled material. Crawler loaders are typical units for digging building excavations, since they can use the loading bucket to dig. • Listing the accessories is hardly possible, since wheeled loaders in particular are universal machines which can be adapted with specially designed grabs, forks, buckets, cranes etc. and can thus be

• PARAMETER : • Engine Power : 520kW • Weight : • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : • Max. New Value : US$ 750,000 • Service Life : 4 Years • Depreciation and Interest : 2.5% per month • Repair Cost : 1.9% per month

• The external hazard resulting from operations is dependent on the type of use and the conditions in the immediate surroundings. • In the case of crawler loaders a survey should be made to determine to what extent these will be used as dozers. For wheeled loaders there is the hazard of collision with other vehicles and, depending on soil conditions, the danger of sinking into boggy ground.

Hydraulic Excavators
• Hydraulic excavators are used for digging and loading. Mounted on a crawler or wheeled chassis, the super-structure is attached to a slewing ring. The usual equipment consists of the boom, the dipper stick and a bucket or a face shovel; in both cases the dipper stick is attached to the boom. A diesel engine provides power and drives one or several hydraulic pumps. All operations are carried out hydraulically. Electric drive is also used for large units in quarry operations. • A multitude of interchangeable accessories makes the hydraulic excavator a universal piece of

• PARAMETER : • Engine Power : 350kW • Weight : 9 Mp • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : • Max. New Value : US$ 600,000 • Service Life : 8 Years • Depreciation and Interest : 1.5% per month • Repair Cost : 1.0% per month • Hazard Class : B

• Operating conditions and the surroundings determine the perils for the equipment. • In general the risk is dependent on the skill and care of the operator.

Cable Operated Excavators
• In contrast to hydraulic excavators, lattice booms may be used in cableoperated excavators where the tools are suspended on cables. Cable-operated excavators can be used for excavating vertically, with a dragline bucket for stripping away earth layer by layer, as lattice mast crane for lifting tasks, or as a carrier unit for driving and drilling. They are constructed with a mobile undercarriage on crawlers or wheels. The smaller, mobile models may also be approved for operation

• PARAMETER : • Engine Power : 700kW • Weight : 250 Mp • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : • Max. New Value : US$ 1.3 m • Service Life : 6 - 10 Years • Depreciation and Interest : 1.8% 1.3% per month • Repair Cost : 1.3% - 0.7% per month • Hazard Class : C

• While cable operated excavators represent relatively low risks in excavation work, there is a high risk of tipping during crane operations, due to overloading or on unstable ground. Particularly endangered are lattice mast cranes where several units are lifting a load simultaneously. In addition to regular maintenance, the training of the operator is of prime significance. Since earth removal

Bucket Excavators
• The typical method of operation for chain bucket wheel excavators is continuous digging and conveyance of the material: buckets which are attached to a chain or wheel dig into the earth, load it, and empty the material onto a conveyor belt. From this belt the earth is transferred to a second conveyor belt or moved to a stockpile. The excavation components are usually mounted on tracks, occasionally on rails, and have electrical or diesel-electric drives. Large stackers, themselves mobile and mounted on a tracked chassis, serve as the connecting link between the mobile excavator unit and the stationary conveyor belt, or between the belt and the stockpile.

• PARAMETER : • Engine Power : • Weight : 10,000 Mp • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : • Max. New Value : US$ 25 m • Service Life : 20 Years • Depreciation and Interest : • Repair Cost : • Hazard Class : A

• These heavy units exert high ground pressures, which not all soils will withstand. Tilting and possible tipping may result. In terraced extraction of the material there is the additional danger of a bench collapsing, with the resulting fall of the excavator. • Low risk, since the equipment is very slow moving. Due to

Drilling and Driving

Pile Driving
• Pile drivers are used to drive piles into the ground. The impact is generated by the hammer, which is dropped on the top of the pile. The hammer may be raised with a cable winch, but steam or compressed air may be used. A leader is used to guide the hammer and the upright pile; the leader is either part of the pile driver frame or may be held by a lattice mast crane. Occasionally the hammer falls free on the head of the pile. • In addition to impact hammers there are also vibratory pile hammers, which do not strike the pile, but which by means of unbalanced weights generate vibrations

• PARAMETER : • Engine Power : • Weight : • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : • Max. New Value : 800,000 • Service Life : • Depreciation and Interest per month • Repair Cost : month • Hazard Class : B

63 t

US$ 12 Years : 1.1% 0.6% per

• Hazards in operation depend in most cases on the location; pile-driving in water, from a scaffolding, etc. The angular pull when setting up the pile can cause tipping.

Drilling Equipment
• Holes of considerable diameter are drilled for positioning steel beams, for laying pile foundations and for positioning concrete piles. Here selfpropelled, universal driving units are used or suitable attachments are utilized in conjunction with cable-operated or hydraulic excavators. The drilling process selected depends on the nature of the ground, the diameter and depth of the hole. • For smaller diameters and in soft ground auger may be sufficient; for larger holes, the sides of which must be protected against cave-ins with steel casings, loose material is drawn inside the casing by a

• PARAMETER : • Engine Power : 150kW • Weight : • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : • Max. New Value : US$ 700,000 • Service Life : 8 Years • Depreciation and Interest : 1.5% per month • Repair Cost : 1.0% per month • Hazard Class : B

• The degree of risk is dependent on the location. The main risk factors are acts of God. Parts subject to wear should not be covered. Relatively low risk. Drill bits, drill rods and casings are normally excluded from coverage.

Rock Drills
• Blasting will be required when, in the course of quarrying or excavation operations, rock is encountered which cannot be ripped with dozers. The explosive is placed in narrow, shallow holes, closely spaced. Holes will also have to be drilled for back anchors for retaining walls, to obtain soil samples, or for injection work. The rock drills used here are usually mounted on crawler track chassis, driven hydraulically, powered by a diesel engine, and operate on the rotating drill or rotary impact principle. In exceptional cases drilling units are also supplied as accessories for mobile hydraulic excavators.

• PARAMETER : • Engine Power : 200kW • Weight : 30Mp • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : • Max. New Value : US$ 280,000 • Service Life : 6 Years • Depreciation and Interest : 1.8% per month • Repair Cost : 1.0% per month • Hazard Class : B

• The degree of risk determined by local conditions : drilling on a slope involves the danger of tipping when shifting position; there is also the danger of rockfalls in the mountains and in quarries. Drill bits and rods must be excluded from coverage.

Road Construction

Compacting Equipment
• To consolidate material so that it will carry a load, it must be compacted by weight or vibration. This is normally done with a heavy roller. To improve compaction performance, rotating, unbalanced weights are often located in the roller drums; these generate vibrations which are transferred to the earth. Backfill material in small excavations is normally consolidated with surface vibrators; to compact earth and rock, simple towed rollers are drawn by dozers or crawler-loaders. In road construction, dieselpowered, self-propelled rollers are primarily used. The type of roller is selected according to the material to be compacted: smoothsurface rollers are used for granular material ( rock, sand, gravel ), while sheepsfoot

• PARAMETER : • Engine Power : • Weight : 32 Mp • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : • Max. New Value : US$ 120,000 • Service Life : static 10, vibro 4 Years • Depreciation and Interest : static 1.3%, vibro 2.5% • Repair Cost : static 0.8%, vibro 1.5%

• Small surface vibrators can easily be stolen; otherwise all types of rollers are very robust in design and are subject to only minimal hazards.

Preparation Plants (bituminous)
• For major road building projects the site equipment includes portable or stationary plants for preparation of the bituminous mixture for the base, binder and surface courses. Such a system, usually in a tower-like configuration, consists of metering devices, drying drums, dedusting system, mixer, mixed material storage hopper, binder storage tanks, filler silo and control center. The finished mixture is conveyed

• PARAMETER : • Engine Power : • Weight : • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : • Max. New Value : • Service Life : • Depreciation and Interest per month • Repair Cost : month • Hazard Class : B

350 t / h US$ 1.0 m 8 Years : 1.5% 0.7% per

• The erection site for the system should be checked for the influences of natural hazards such as earthquakes, flooding and storm. • The insurance risk is dependent solely upon the location and can generally be regarded as low. Machinery

Fineshers
• Road finishers are combination units for fabricating the bituminous base, binder and surface courses as well as for the laying of concrete pavements. In the case of asphalt pavements the mixture is delivered by lorry, transported and distributed in the finisher, perhaps heated and agitated, and then placed and at the same time pre-compacted by a screeding beam, which is hydraulically controlled and often heated. The height of the beam is controlled electronically with a levelling unit installed in the finisher or by means of laser beam. The machines advance on tracked or tyred chassis in phase with the progress of the construction work; concrete pavements finishers may also run on rails. The effective width can be adjusted in steps by adding extensions. Special equipment has been developed for the sealing of dam surfaces; these travel along the crown of the dam and cover the face down to the foot.

• PARAMETER : • Engine Power : • Weight : 28 Mp • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : • Max. New Value : US$ 350,000 • Service Life : 6 Years • Depreciation and Interest : 1.8% per month • Repair Cost : 1.5% per month • Hazard Class : A

• Since this is very slow moving equipment which travels on a prepared base, pavement finishers are endangered primarily by external influences. The fire hazard is considerably higher for asphalt finishers than for concrete finishers. All types, however, are endangered by construction traffic, and in

Driving Shields
• Using driving shields it is possible to head sewage conduits and tunnel tubes economically, particularly in built-up areas, without influencing existing buildings or interrupting the traffic flow. The heading shield is made of steel and protects the forward area of the tunnel tube against material as it breaks out. The shield is advanced hydraulically as construction progresses, the hydraulic presses are supported on sections of tunnel already finished. In order to reduce the high driving forces the shield is often divided into segments which are then advanced individually (blade shield). To facilitate removal of the rock and to protect the working place, the shields are often

• Values are high and depend on the equipment used.

• When rock is encountered the cutters on the shield may be damaged or the entire shield may be thrown off course. Damage resulting from the operations themselves should be excluded, as well as loss of shield when it is later determined that heading cannot be carried out to completion. Recovery of a shield after damage may be very difficult

Partial-cut Machines
• The material at the face can be loosened during tunnel construction with partial cut machines, which are especially suited for rock which is not too hard and for asymmetrical cross-sections. A slewing arm is attached to a mobile undercarriage (usually tracked); this arm carries a milling head which loosens material at various points on the face. The slewing arm can be fitted with various types of cutting heads matching the type of rock. To stabilize the cutting face and the tunnel tube until the lining is completed, this work is normally carried out under the protection of a shield, which is advanced hydraulically, following the progress of the work.

• PARAMETER : • Engine Power : • Weight : • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : • Max. New Value : • Service Life : • Depreciation and Interest per month • Repair Cost : month • Hazard Class : D

6 Years : 1.8% 1.2% per

• Cave-in of the tunnel tube, ingress of water, fire and explosion are the potential dangers to which partial-cut machines are exposed and which often result in a total loss.

Full-cut Machines
• The pre-requisite for the utilization of full-cut machines for heading the complete tunnel cross section at one time is, apart from rock which is not too hard, a symmetrical tunnel cross-section. Full-cut machines are generally designed as comprehensive units for tunnel heading and lining, and may reach a length of 50 m. underneath a protective shield at the face, which is advanced hydraulically and which may be divided into individual blades to reduce wall friction, a cutting head rotates, which is equipped with cone bits or constructed as a cutting disk. Behind the cutting head are holding and follower shields to support the tunnel walls and roof, as well as the laying equipment for the tunnel lining elements, the so-called tubbings. The

• PARAMETER : • Engine Power : • Weight : • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : • Max. New Value : • Service Life : • Depreciation and Interest per month • Repair Cost : month • Hazard Class : D

6 Years : 1.8% 1.2% per

• As factors in underground operation, tunnel tube caveins, ingress of water, fire and explosion are typical hazards, which may result in a total loss. In case of partial losses there are usually problems in effecting repairs, since the machines fill the entire crosssection of the tunnel and are accessible with difficulty. High

Drilling Jumbos
• Hard, stable rock must be blasted, since it cannot be removed economically with machinery. Shot holes are drilled in the working face in preparation for the blasting. Specially drilling cradles, so-called drilling jumbos, have been developed for this purpose; these operate several rock drills simultaneously. These drilling jumbos must be removed to a rear tunnel area prior to blasting.

• PARAMETER : • Engine Power : • Weight : • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : • Max. New Value : 500,000 • Service Life : • Depreciation and Interest per month • Repair Cost : month

US$ 6 Years : 1.8% 1.0% per

• In addition to the dangers of tunnel tube cave-ins, ingress of water, fire and explosion, the primary peril is the collision with transport vehicles, which move quickly in restricted space. An effective ventilation system must be provided to improve visibility within the tunnel.

Chain-Bucket Dredgers
• Floating dredgers are used for underwater excavation work, such as deepening channels or harbour basins. The most familiar is the chain-bucket dredger, in which a ladder chain carrying the buckets is mounted in a rotating configuration at the center of a ship which is cut through longitudinally. The buckets dig into the material, convey it upwards and empty it into a chute, from which the material slides into an adjacent bottom-dump barge (scow) or onto a floating convneyor

• PARAMETER : • Engine Power : • Weight : • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : 1000 lt • Max. New Value : • Service Life : • Depreciation and Interest per month • Repair Cost : month

Bucket US$ 7.4 mi 20 Years : 0.8% 0.5% per

• The main peril to all floating dredgers is sinking. In particular for work at sea attention must be paid to setting up satisfactory emergency plans for imminent storms. • Like all floating equipment, the floating dredger should not be

Suction Dredgers
• Suction dredgers are used for underwater excavations when the bed is composed of gravel or soft material. They consist essentially of a centrifugal pump, a power supply unit, a suction tube, and a transportation pipeline. Everything is located on a floating operations platform. The pump draws a mixture of water and material through the suction port and moves this through a floating pipeline or a pipeline on the channel bed to the deposit area. In the case of a suction dredger with cutting head, which is used where the ground is difficult to loosen,

• PARAMETER : • Engine Power : Pump 3800 kW • Weight : • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : • Max. New Value : US$ 14 mi • Service Life : 20 Years • Depreciation and Interest : 0.8% per month • Repair Cost : 0.5% per month • Hazard Class : D

• Storms and subsequent sinking are the major perils to all floating equipment, ie the dredging equipment and the floating dredging pipeline. A suitable plan must be worked out to deal with storms. The slurry causes extreme abrasion at the suction port, pipelines and pumps. This equipment,

Ocean-going Rigs
• A floating ocean going rig consists of a pontoon and usually four caissons which pass through the pontoon at its conrners. With the caissons raised, the platform to towed to the intended site, where caissons are lowered to contact the seabed; the platform then lifts itself out of the water, climbing up the caissons by hydraulics. The advantage of using the ocean going rigs for construction is that it is exposed to wave action only during the relatively short transfer period to the next location. It is for this reason that it is normally used as the base for large equipment such as pile drivers and cranes, but can itself be utilised as a transportation and lifting unit. All the

• The design and equipment of ocean-going rigs are adapted to suit the particular construction site and can in no way be standardized . It is for this reason that new values fluctuate widely. • Service life : 20 years • Hazard Class ; D

• Ocean-going rigs are normally used for special construction assignments at sea. They usually cannot be towed to a safe port in case of a storm. In addition to taking storms and wave action into consideration, the organisation of the work must be examined for hazardous features, such as dropping large, pre-fabricated elements. • Whether the units are considered

Compressed Air and Injections
• Large volumes of compressed air may be required and produced at construction site powering pneumatic tools (such as pneumatic rock hammers), for ventilation of tunnel tubes, to hold back water with over pressure in underwater operations, and for tunnel and casing advancing. Diesel or electric power compressors are used to compress the air into air reservoirs. Differentiation must be made between tool-operating air and ventilation for personnel. The air for personnel must be cleaned in oil and air separators prior to use. Auxiliary

• PARAMETER : • Engine Power : • Weight : • Carrying Capacity : • Load Moment : • Throughput : • Nominal Fill : • Max. New Value : • Service Life : Years • Depreciation and Interest compressors 1.5% per month • Repair Cost : 0.8% per month

US$ 110,000 Compressors 8 : compressors

• As part of the general site facilities, compressors are exposed only to minimal operational hazards. The main dangers are posed by external perils such as flooding, fire and rock fall. A special assessment must be made in cases where systems are mounted on pontoons, which

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