Fundamental investigation of structural design optimization of guardrails based on collision simulation

Abstract

Guardrails are essential structures for protecting vehicles and saving human lives when traffic accidents occurred. When a vehicle collides with a guardrail in the traffic accident, some kinetic energy of the moving vehicle can be absorbed or reduced by the guardrail according to its energy absorption capacity. In the present work, we aim to investigate structural design optimization of guardrails based on collision simulation to enhance their energy absorption capacities. To reproduce a real collision condition for structural design optimization of guardrails, in the collision simulation of a vehicle collides with guardrails, we construct the finite element model of the guardrail considering details of the shape of the guardrail, the bolts connecting the guardrail and the post, and the efficient model of soil. A verified finite element model of vehicle is adopted for real collision simulation. According to the results of collision simulation, we perform structural design optimization of the guardrail using the optimization method of central composite designs, where three design variables representing its cross-section shape are chosen. For the results, collision simulations using the constructed finite element models of the guardrail and the vehicle were smoothly performed. At last, based on the optimization method of central composite designs, the optimal cross-section shape of the guardrail was determined, which could absorb the most kinetic energy of the moving vehicle.