Stress Waves in a Laminated Medium Generated by Transverse Forces

A laminated medium composed of alternating layers of two homogeneous isotropic elastic solids is suddenly subjected to a spatially uniform distribution of transverse forces, which are applied in a plane normal to the layering. The resulting two dimensional transient wave propagation problem is analyzed by means of modal analysis. The normal and shear stresses at the interfaces are expressed as infinite integrals that are integrated numerically for not too large values of time. For larger values of time, the integrals are approximated by the method of stationary phase. The predominant contribution to the interface shear stress comes from the head of the pulse approximation. The normal stress at the interface, which is composed of several contributions, is oscillatory, and the interface bonds may thus be subjected to tensile stresses.