Rollover Analysis of a Bus Using Beam and Nonlinear Spring Elements

摘要

In case of bus rollover, the body structure of a bus should be designed to ensure the survival space for passengers. So, this study focused on evaluating the rollover strength through a computer simulation using the commercial code, LS-DYNA3D at the initial stage of vehicle development. For this purpose, section structure of the bus frame was first modeled using simple beam elements, and the impact boundary conditions required by ECE regulation No. 66 were applied. In order to validate the beam element model, the simulation results were compared to those of shell element model. Since the analysis error with beam element model was mainly caused by the difference in strain energy at the T-shaped connecting joint, the joint connection was modified with nonlinear springs to account for the local buckling. With the improved beam model, the results were in a good agreement to shell element model, but the simulation times were much reduced.