Finite Element Approach to Stress Wave Problems

The description of a computer code is presented for application to two-dimensional stress wave propagation problems through layered elastic materials. The code is based on the finite element method as opposed to the more usual finite difference methods usually applied to this class of problem, so as to be able to treat the more complex boundary and interface conditions usually encountered in problems of interest. The code can treat either the axisymmetric or plane (stress or strain) problem. Numerical results are presented for two one-dimensional (plane and spherically symmetric) problems, and comparisons made with known analytic solutions. The results for a two-dimensional problem are also presented and compared with a solution obtained by finite difference methods. These results generally indicate that displacement computations are quite satisfactory. However, for problems with sharp stress fronts, oscillations in the stress computations in the vicinity of the front are induced.