Finite element investigation of the influence of material properties on the crushing characteristics of in-plane loaded composite sandwich panels

In the present paper, the explicit finite element code LS-DYNA3D was used to investigate the influence of selected material properties in the crash energy absorption characteristics of composite sandwich panels subjected to in-plane compressive loading. The first step in this investigation was to simulate as accurate as possible representative tests corresponding to the collapse modes that occurred in a series of static edgewise compression tests performed in the National Technical University of Athens (NTUA) using various types of composite sandwich panels. These sandwich panels were candidate materials for use in the new type of composite front-end bumper of a transportation vehicle. Subsequent to the precise reproduction of the collapse modes, a step-by-step approach was followed in order to examine the influence of selected faceplate and foam core material properties on the crash energy absorption characteristics of the in-plane loaded sandwich panels. More specifically, several series of finite element models were created, by altering the value of only one material parameter per time of the initial FEA models used for the simulation of the sandwich panels collapse modes. The results from the processing of these series of FEA models were used to create figures that graphically depict the influence of the material properties on the energy characteristics. More over the simulation results were analysed in order to express by means of simple linear or polynomial functions the dependence of the crash energy absorption characteristics on the sandwich material parameters. The findings of this series of investigations were recorded aiming to be used as reference to the design of composite sandwich panels in various crashworthiness applications.