Crash analysis of thin-walled structures with an elasto-plastic explicit finite element method

Abstract

To evaluate the crash-worthiness of a car, the dynamic response of auto-body components has to be correctly simulated for various loading conditions. Simulation of thin-walled structures has been carried out by an elasto-plastic explicit finite element method with shell elements. The present algorithm adopts the plastic-predictor elastic-corrector (PPEC) scheme in stress integration in order to keep track of the stress-strain relation for the rate-dependent model accurately. Experimental results from both static and dynamic tests with the tension split Hopkinson bar apparatus are interpolated to construct the Johnson-Cook and a modified Johnson-Cook equation as a constitutive relation, that should be applied to simulation of the dynamic behavior of auto-body structures. Numerical simulations show remarkable difference in the reaction force and impact energy absorption between the static model and the dynamic model.