A consistent approach for mixed stress finite element formulations in linear elastodynamics

In this paper, a mixed stress formulation for linear elastodynamic analysis based on a modified Hellinger–Reissner functional and a consistent approach for selecting finite element approximations are presented. The key idea in this new approach is to choose stress approximations by taking into account for suitable modes to equilibrate inertia forces. Feasibility and effectiveness of the proposed approach are numerically verified through three benchmark tests.