These are engaged only for hauling or conveyance of excavated earth or
materials, holding capacity and speed of movement are essential
Engine of adequate hauling power will have to be fitted.
They include, Tractors, Trucks, Dumpers, Trolleys, Wagons and
TRUCKS AND DUMPERS
These help in conveyance of material excavated by shovels and loaded
Trucks only carry the material, while the dumpers have also the facility
for self dumping of the material at a specified place, relatively low
hauling costs because of their high travel speeds.
Very broadly, dump trucks may be said to be general-purpose vehicles,
used to haul earth, gravel, sand, relatively small rock or ore, and mixed
The weight capacity of a truck may limit the volume of the load that a
unit may haul.
The productive capacity of a truck depends on the size of its load and
the number of trips it can make in an hour.
The number of trips completed per hour is a function of cycle time.
Truck cycle time has four components:
The varieties are:
Dumper trucks-with rear dump facility.
Dumper trucks with side dump facilities.
Bottom-dump tractor-trailer units.
Side dump tractor-trailer unit.
Rear dump tractor-trailer unit. Hydraulically operated rear-dump truck.
100-cu-yd struck capacity rear dump truck
Dragline, loading a bottom-dump wagon
The capacity of a dump truck (or similar hauling equipment) may be expressed
in at least three ways:
The rated capacity, expressed in tons
The truck volume, expressed in cubic yards
The heaped capacity, expressed in cubic yards.
The ranges of sizes and capacities:
Widths-2.44 m to 4.20 m (8'.0" to 13'.8")
Axle weight (loaded}-18,000 - 22,000 lbs (8167 to 9982 kg)
Gross vehicle weight-Normal 13600 - 20400 kg (30,000 - 45,000 Lbs)
Modified designs 31800 to 40,800 kg (70,000 - 90,000 Lbs)
Loading capacities 2.833 to 15 cum (100 to 530 cuft)
(Higher capacities are also coming into use now-a-days)
Side dump trucks-dump angle 55° (In some 90° can also be achieved)
The activities and conditions which control the efficiency and capacity of
the trucks and dumpers may be listed as :
Loading: Size and type of loading frame.
Type and condition of material to be loaded.
Capacity of hauling unit.
Skill of operator.
Forward Haul: Performance of haul unit; Haul distance; Haul-Road
condition, grades ,other conditions which affect haul speed.
Dumping: Destination, maneuverability of unit, type and condition of
material, moving facilities in dumping area.
Return Haul: Ability of hauling unit.
Condition of haul road; grades, other affecting conditions.
Loading equipment type and place or location of loading equipments.
Truck capacity (tons) Body size
10 6.6 cu yds
These are the trucks which are fitted with automatic unloading devices. The
loading is normally done by loading shovels or loaders. These trucks have
capacities as high as 53 tonnes. These trucks can be rear dump trucks, bottom
dump trucks and side dump tucks.
These are most versatile, labour saving hauling equipment for horizontal
movement of materials such as bricks, aggregates, sanitary fittings, scalffolding
and fluids such as wet concrete. These are usually diesel-powered vehicles
requiring only the driver, and can traverse the rough terrain on many building
sites. They are available in different sizes and varieties giving many options
such as two or four -wheel drive, hydraulic or gravity-operated container, side
or high level discharge, self-loading facilities and specially equipped dumpers
for collecting and transporting crane skips.