A computer program developed to predict the behaviour of an automobile striking a protective barrier is described. The barrier is idealised as a structural framework of arbitrary configuration and the automobile as a body surrounded by a cushion of springs. Large displacements and inelastic behaviour, including hysteresis effects on unloading, are considered in the barrier structure. The automobile slides along the barrier, and the effects of normal forces, friction forces, and wheel drag forces are considered in determining its motion. Input data to the program consist of the configuration of the barrier, the properties of the barrier members and automobile and the trajectory of the automobile before impact. Output consists of time histories of automobile positions, velocities and accelerations, barrier deflections, and barrier member forces. The procedure used to solve the problem is described. The capabilities and limitations of the program are discussed and results for two example barriers are presented. (Author/publisher)
Abstract