How empty cans could make Thailand’s roads safer

Nearly 12,000 cans packed into re-usable ‘crash boxes’ could protect drivers and passengers on Thailand’s roads. The innovation developed by Cranfield University focuses on addressing the devastating outcomes of high-speed collisions involving highway maintenance trucks, which each year kills around 70 people in the country.

Dr Hessam Ghasemnejad, Reader in Aerospace Structures, is leading the work at Cranfield which is supported by the Royal Academy of Engineering and Thai partners.

In 2021, 28% of all vehicle accidents in Thailand were rear-end collisions. These types of collisions often happen at high speeds (60mph+) and the fatality rate increases when one of the vehicles involved is significantly more rigid than the other – for example a car hitting a heavy truck or a motorway maintenance vehicle.

Dr Ghasemnejad is developing an innovative new way to protect drivers and passengers in these types of accidents using things we throw away every day: aluminium cans.

Researchers are creating re-useable crash boxes full of aluminium cans that fit on the back of road maintenance vehicles. Each box will contain 11,776 cans arranged in four ‘stacks’ of 2,944, and all the cans will be filled with natural waste like coconut fibres. When a crash happens, the cans will crush, absorbing a significant amount of the energy from the collision and lowering the chance of injury for both drivers and passengers.

As well as keeping people safe, the boxes are all designed to be reusable with the cans simply replaced after a crash and the crushed cans recycled.

Initial simulations were based on numerical modelling and analytical calculations, but physical tests have already taken place at Cranfield Impact Centre.

Dr Hessam Ghasemnejad said: “Accidents on roads happen all around the globe every day. Adding crash boxes like these onto road maintenance vehicles will keep both drivers and road workers safe by absorbing much of the energy that makes high speed road collisions so dangerous.

“Using recycled materials for these boxes makes sense because crashes are inherently destructive. By using things have been recycled – and can be recycled again in future - it means there is little to no waste compared to using non-recyclable materials that would have to be thrown away after a single impact.”

The project is aiming to design two different waste-filled crash boxes for road service vehicles, with a goal to implement waste-filled portable crash boxes for at least three different road service vehicles from different operators.