The physics of loading a truck

The physics of loading a truck

Securing cargo onto a truck is very much a question of good knowledge and understanding of the basic physics of the situation that can help avoid accidents down the road.

Cargo that is inadequately secured on a truck can potentially be life threatening for the driver, pedestrians as well as drivers of other vehicles.

Scania sees highlighting the importance of correct cargo-loading and securing as an effective way of improving road safety. That’s why cargo securing is one of the six major categories in Scania Driver Competitions – the world’s biggest competition for testing drivers’ skills.

The basic physical principle is that when a vehicle brakes, the load will strive to continue in its original direction independently of the vehicle, unless of course it is properly secured.

Securing cargo

“Securing cargo on a truck is about taking into account four very important parameters – the friction between the cargo and the truck bed, the cargo’s dimensions, its weight and center of gravity,” says Peter Andersson, one of the owners of Mariterm, a Swedish company that conducts cargo securing courses for the trucking and maritime industries. “Cargo should never tip or slide. That is when accidents happen.”

According to Andersson, the most dangerous instances for a truck loaded with cargo occur during hard and sudden braking, strong acceleration, hard cornering on roundabouts and rapidly changing lanes. Without appropriate restraints, these are the moments when the physical forces on the cargo are the strongest and potentially most catastrophic.

Drive calmly

“Many say that the best advice is to drive calmly, which is true. At the same time, you never know when something unforeseen is going to happen,” says Andersson.
According to international rules, cargo restraints in the forms of blocking and lashing should be able to withstand 0.8 times the weight of the cargo during heavy braking, and 0.5 times the weight during a turn.

Besides center of gravity, friction, and weight, some other things to consider when loading a truck include the rigidity of the cargo, the load distribution, and the choice of an appropriate vehicle.

Combined rail transport

Another important point when securing cargo on a truck is that maybe it will continue its journey on a combined rail transport or on a ship, both of which pose different force scenarios on the cargo than road transport.

“In our training, we urge people to think one step ahead and do it right from the beginning,” says Andersson.

The driver’s responsibility

So who is ultimately responsible?

“That is a complicated question and it differs from country to country,” says Andersson. “Many drivers often go to pick-up a pre-loaded trailer and expect it to be fine. In Sweden, the driver is ultimately responsible whereas in Germany it is the driver, the sender, and the trucking company that share responsibility. But ultimately the driver should always make sure that his rig is secured correctly.”

Facts

The brand new revised European Best Practice Guidelines on Cargo Securing for Road Transport, which is published by The European Commission and available on all European languages, contains basic principles for cargo securing as well as detailed instructions for some types of cargo. It also contains a handy Quick Lashing Guide with practical advice and instructions to all persons involved in securing cargo on vehicles. including carriers and shippers.