Impact Analysis of Composite Sandwich I-Lam System

Due to increased traffic volumes and damaged bridge structures, there is a pressing need to develop a collision protection system for highway bridges against over-height truck impact. In this study, a linear elastic model for impact response of bottom face sheet-rigidly supported sandwich structures including shear-off effect is developed. The solutions of discrete model, concentrated and distributed loading cases for collision protection I-Lam system are obtained, of which the contact force history and maximum deflection are predicted. Compared to the LS-DYNA finite element analysis (FEA), the proposed analytical methods show their accuracy and simplicity in predicting the impact response. The discrete model shows a better correlation with FEA predictions; while the model with distributed forces overestimates the deflection of the top face sheet but under-evaluates the peak contact force. The relatively simple and accurate models developed can be used to approximate the impact response of rigidly supported sandwich structures.