Stress wave propagation in composite materials

The linear constitutive relations and the failure criteria of composite mat erials made of thermoviscoelastic solids are presented. The post-failure ma terial behavior is proposed and the dynamic finite element equations are fo rmulated. However, a nonlinear term is kept in the energy equation because it represents the effect of the second law of thermodynamics. A general pur pose nonlinear three-dimensional dynamic finite element program COMPASS is upgraded and employed in this work to investigate the interdependence among stress wave propagation, stress concentration, failure progression and tem perature elevation in composite materials. The consequence of truthfully in corporating the second law of thermodynamics is clearly observed: it will a lways cause temperature rise if there exists a dynamic mechanical process.