Evaluation of crashworthiness of a carbon-fibre-reinforced polymer (CFRP) ladder frame in a body-on-frame vehicle

This paper investigates the opportunities of lightweighting a steel ladder frame, which is a primary structural component in a body-on-frame vehicle, using a carbon-fibre-reinforced polymer (CFRP) composite. The finite element (FE) model of a 2007 Chevrolet Silverado, which is a body-on-frame pickup truck, is selected as a baseline. The steel ladder frame of the baseline vehicle is replaced with a CFRP ladder frame. A two-dimensional triaxial carbon-thermoset-braided composite is utilised as the substitute for steel. The structural performance of the CFRP ladder frame is evaluated by FE simulations of stiffness tests and frontal impact tests. The results show that the CFRP ladder frame with twice the thickness of the original frame rails can provide a similar performance to the original steel ladder frame in terms of its stiffness and impact energy absorbing capability. Consequently, the weight reduction of the original steel ladder frame reaches up to 32% in the CFRP ladder frame.