Qatraneh Weighbridge: Rear Tandem Overload
At the Qatraneh weighbridge on the Desert Highway you are checking a three-axle rigid truck before the 180 km run to Amman. The manufacturer plate shows gross vehicle weight 26,000 kg, front axle limit 7,500 kg and rear tandem limit 19,000 kg. The operator’s road permit for this route allows a maximum gross weight of 25,500 kg. You are loaded with 18 pallets of ceramic tiles, each rated at 1,000 kg. The weighbridge reads front axle 5,100 kg, rear tandem 21,300 kg, gross 26,400 kg. Four pallets sit directly behind the cab; fourteen sit over the rear tandem. The dispatcher says the customer’s unloading slot closes in four hours and asks you to 'sort it out on the road.' The weighing officer is watching. You have a pallet truck, but no crane.
1. Calculate the gross and axle overloads, and state whether the truck may leave the weighbridge as loaded. Show your arithmetic.
Read the worked answer
Gross overload = 26,400 kg − 25,500 kg = 900 kg over the permit.
Rear tandem overload = 21,300 kg − 19,000 kg = 2,300 kg over the axle limit.
Front axle spare capacity = 7,500 kg − 5,100 kg = 2,400 kg available.
The truck may not leave as loaded. It exceeds both the permit gross weight and the rear tandem design limit. The front axle being under its limit does not cancel either problem: axle limits and gross weight are separate checks. Redistribution alone cannot fix the gross overload unless at least 900 kg is removed or the permit is varied. The weighing officer should see a corrected weigh ticket before the truck moves, not a promise to adjust later.
2. Propose a practical load adjustment using whole pallets, and verify the new axle and gross figures.
Read the worked answer
Remove one pallet from the rear group and move two pallets from the rear group to the front.
New front axle = 5,100 + 2,000 = 7,100 kg (limit 7,500 kg).
New rear tandem = 21,300 − 1,000 − 2,000 = 18,300 kg (limit 19,000 kg).
New gross = 25,400 kg (permit 25,500 kg).
All three checks pass. Do not move three pallets forward: the front axle would become 8,100 kg, which is 600 kg over. After adjustment, re-weigh and keep the ticket. If the pallets cannot be moved safely with the pallet truck, or cannot be re-secured on the deck, offload to another vehicle rather than improvising on the highway.
3. Explain the handling and braking risks of the original load, and what you would tell the dispatcher.
Read the worked answer
The original load puts 2.3 t too much on the rear tandem. That overloads tyres, suspension and rear brakes, raises tyre-burst risk in summer heat, and makes rear grip and brake balance less predictable. The front axle is light, so steering authority is reduced, especially in crosswind, on wet patches or over a diesel spill. Stopping distance can increase, and an emergency stop may produce uneven braking or loss of direction.
Tell the dispatcher: 'I cannot legally or safely move. The rear tandem is 2.3 t over its limit and the gross is 900 kg over the permit. I am adjusting the load and re-weighing; the ETA will move.' Send the weigh ticket. Do not accept 'sort it out on the road': once on the highway there may be no safe place to redistribute, and the driver remains responsible for the vehicle's condition.