Wave propagation in a weak viscoelastic layer produced by prescribed velocity on the boundary

Four models are employed to analyze wave propagation from impact on a weak viscoelastic layer. Each model is exploited on the basis of its particular strength and all four are used co-operatively in a study that overcomes the limitations of each. These models are: a numerical finite volume model serving as reference which couples motions of projectile and layer, a two-dimensional viscoelastic model with prescribed pressure on the boundary, and two versions of a three-dimensional axisymmetric elastic model; one with prescribed pressure at the boundary, and one with prescribed velocity at the boundary. This last model superimposes the responses from several external annular pressure segments of unit intensity with time-dependent weights yielding a combined response equal to the prescribed instantaneous velocity. Stress histories from all models are comparable with greatest difference near the excited boundary.