Effect of Barrier Type on Rail Deformation Pattern

Two barriers commonly used to evaluate the response of a vehicle in a frontal impact are the rigid barrier and the offset deformable barrier, each produces different deformation patterns. One possible cause of the difference is that an impact into a rigid barrier generates significantly greater stress waves than impacts in the real world resulting in final deformation patterns that are different from those seen in the field. To evaluate this hypothesis, models of two types of rails, one for a truck design and one for a passenger vehicle design undergoes two different types of impacts. Both rails are analyzed using an explicit dynamic finite element code. Results show that the energy perturbation along the rail depends on the barrier type and that the early phase of wave propagation has very little effect on the final deformation pattern of both rails. These results imply that in the real world conditions, the stress wave propagation along the rail has very little effect on the final deformed shape of the rail.