Because the maximum gross weight on the road is fixed by law, every kilogram saved from the trailer's tare weight is added directly to the transportable payload. Lightweight trailer prototypes in the academic literature show that a tare weight reduction of up to 2.5 tonnes is technically feasible with composite-intensive designs.
Which Composites, and Where?
Glass fibre reinforced polymer (GFRP) panels are used in body walls, foam- or balsa-cored sandwich structures in the floor, and carbon fibre in the beam zones exposed to the highest stresses. Steel remains only in areas where point loads concentrate, such as the king pin and axle connections — resulting in a hybrid structure.
Gains and Points to Watch
- More payload per trip or lower fuel consumption
- Longer service life thanks to natural corrosion resistance
- Fatigue design is critical at metal-composite joint details
- Repair procedures and damage detection require different expertise than steel
- The initial investment cost must be calculated together with fuel and payload gains
When the right application area is chosen, composite lightweighting is a proven engineering strategy that lowers the vehicle's whole-life cost and improves fleet efficiency.
References
- Madhusudhanan, A. K., Na, X., Boies, A. & Cebon, D. (2021). Effects of semi-trailer modifications on HGV fuel consumption. Transportation Research Part D: Transport and Environment, 92, 102717. DOI: 10.1016/j.trd.2021.102717