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Trucks and Hauling Equipment
1. TRUCKS AND HAULING EQUIPMENT
CONSTRUCTION EQUIPMENTS AND METHODS
By- VARUN Y.S.
RACHANA AGUTALE
CONSTRUCTION TECHNOLOGY AND MANAGEMENT
VNIT
2. TRUCKS
๏ด Trucks are hauling units that provide relatively low hauling costs
because of their high travel speeds.
๏ด Trucks provide a high degree of flexibility permitting modifications
in the total hauling capacity of a fleet and adjustments for
changing haul distances.
3. ๏ด Most trucks may be operated over
any haul road for which the surface
is sufficiently firm and smooth and
on which the grades are not
excessively steep.
๏ด Some trucks now in use are
designated as off-highway trucks
because their size and total load are
larger than that permitted on public
highways. These trucks are used for
hauling materials on large project
sites, where their size and costs are
justified.
4. TRUCKS CLASSIFICATION
๏ดTrucks may be classified according to a number of factors
including:
1. The method of dumping the load.
a) Rear dump trucks
6. 2. The size and type of engine
-gasoline, diesel, butane or propane
3. The kind of drive
-two wheel, four wheel or six wheel
4. The no. of wheels and axles, and the arrangement of driving wheels
5.The class of material hauled
-earth, rock, coal or ore
6. The capacity
-gravimetric (tons) or volumetric (cubic yards)
7. The type of frame
- rigid frame or articulated
7. RIGID FRAME REAR DUMP TRUCKS
๏ They are suitable for use in hauling many types of materials.
๏ The shape of the body, such as the extent of sharp angles &
corners,& contour of the rear, through which the materials
must flow during dumping, will affect the ease or difficulty of
loading & dumping.
๏ Continuous use under severe conditions requires a heavy-duty rock body made of high-tensile
strength steel.
๏ They can navigate grades of 20% for short distances.
8. ARTICULATED REAR-DUMP TRUCKS
๏ They operate through high rolling resistance material and in
confined working locations.
๏ The wheel drive, high clearance and low pressure radial
tires combine to produce a truck capable of moving
through soft or sticky ground.
๏ They can operate on grades up to about 35%.
๏ Most common are the 4x4 models but there are larger 6x6 models. They usually have high
hydraulic system pressure (dumping cylinder hoists the bed faster) and the bed achieves a
steeper dump angle.
9. CAPACITIES OF TRUCKS AND HAULING EQUIPMENT
๏ด Three methods of rating the capacities of trucks:
1) Gravimetric: the load it will carry, expressed as a weight.
2)Stuck volume: the volumetric amount it will carry, if the load is water level in
the body.
3)Heaped volume: the volumetric amount it will carry, if the load is heaped on a
2:1 slope above the body.
10. TRUCK SIZE AFFECTS PRODUCTIVITY
Small Trucks
Advantages:
1. Maneuvering flexibility, which may be an advantage on restricted work sites.
2. Speed, can achieve higher haul and return speeds
3. Production, little impact if one truck breaks down
4. Balance of fleet, easy to match number of trucks to excavator production
11. Disadvantages of Small Trucks:
1.Number, more trucks increases operational dangers in the pit, along the haul road and at the
dump.
2.More drivers required, more needed for a given output.
3. Loading impediment, small target for excavator bucket.
4. Positioning time, total spotting time greater because of the number required.
12. Large Trucks
Advantages:
1.Number, fewer needed for a given output.
2.Drivers required, fewer needed for a given output.
3. Loading advantage, larger target for the excavator bucket.
4. Positioning time, frequency of spotting trucks is reduced.
13. Disadvantages of Large Trucks
1.Cost of truck time at loading is greater, especially with small excavators.
2.Loads heavier, possible damage to the haul roads thus increasing the cost of maintenance of
the haul road.
3. Balance of fleet, difficult to match no. of trucks to excavator production.
4.Size, may not be permitted to haul on highways.
15. 1) Number of bucket load:-
Balanced number of bucket load = Truck
capacity/bucket capacity
2)Load time and Truck load volume:-
3) Haul Time:-
Haul time = haul distance
haul speed
16.
17. 4)Return time:-
Return Time = Return distance
Haul speed
5) Dump Time:-
*Type of hauling unit
*Congestion in the dump area
6) Truck cycle time
7) Number of trucks required:-
=Truck cycle time
Excavator cycle time
18. 8) Production:-
= truck load*no of trucks*60min*Efficiency
Truck cycle time
Production Issues:-
1) Reach of the excavator
2) Dumping height of the bucket
3) Width of the bucket
19. Tyres:-
1)Proper tyre size
2)maintaining correct air pressure
3)Based on resistance, which surface of the
road offers to penetration
rigid road surface- small dia high pressure
yielding road surfaces- large dia low pressure
TMPH(tonmilesperhour)=Avg tyre load x Avg
speed during a dayโs operation
20. Truck safety:-
1) Conduct hazard assessment of the work
everyday, and ensure operators and drivers are
aware of hazards
2) Ensure berms are adequately built
3) operator should follow all operating signals
4) Use of spotter while backing with blind spot
5) Should stay out of vehicle travel path
6) wear high visibility safety clothing