Load restraint and axle limits on a tipper
A tipper truck has a gross vehicle mass of 24,000 kg and a tare of 11,000 kg. Its front axle limit is 6,500 kg and its rear axle group limit is 17,000 kg. The driver loads 13,500 kg of wet sand, placing most of it toward the rear of the bin to speed up tipping. Before departure the driver checks that the tailgate is latched and the load is level with the top of the bin. The truck has a load restraint system of rated straps, but the driver uses only two straps across the rear because the sand 'won't move'. The trip is 40 km on sealed roads with one roundabout.
1. Calculate whether the truck is within its GVM and discuss the axle-load risk of loading toward the rear.
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GVM check: tare 11,000 kg plus load 13,500 kg equals 24,500 kg, which exceeds the 24,000 kg GVM by 500 kg. The truck is overloaded and must not depart until 500 kg or more is removed. Axle risk: loading toward the rear shifts mass onto the rear axle group. Even if the total were corrected, concentrating load at the rear could push the rear group over 17,000 kg while leaving the front axle under 6,500 kg. The front axle also needs enough load for steering grip. The driver should redistribute the load forward to balance the axles and re-check axle masses, not just total mass, before departure.
2. Is two straps across the rear of a level sand load adequate restraint? Explain the principle that applies.
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No. Load restraint must prevent the load from moving in any direction under forces likely to be encountered, including braking, acceleration, cornering, and the roundabout on the route. Sand is a loose aggregate that can shift and spill; a level load with a latched tailgate is not by itself a restraint system. The driver should use the rated restraint system as designed, with enough straps or a tarpaulin and restraint arrangement to contain the load, and should check that the tailgate is secure. Relying on two straps because 'sand won't move' ignores the forces at a roundabout and during braking. The correct approach is to follow the vehicle's load restraint guide and use the rated equipment to secure the load against movement in all directions.