DYNAMIC BEHAVIOUR OF INTERFACIAL CRACK TIPS IN A WEDGE-SHAPED BIMATERIAL SPECIMEN UNDER IMPACT

摘要

A specimen partially bonded by two wedge-shaped plates of dissimilar materials is impulsively loaded. Tip response of a crack along the interface is investigated to the action of stress wave with transmission and reflection. A hybrid technique of combining dynamic photoelasticity with dynamic caustics is used to analyze the wave propagation in media and the singular behavior of crack tips. Based on some characteristic dimensions of the caustic curves belonging to each medium, the complex stress intensity factors of the interfacial crack tips are computed, showing an oscillation history of the modulus with the passing of the compressive wave and the intersection of the reflected tensile pulse.