A new elastoplastic shell element formulation for DYNA3D

The analysis of shell structures undergoing dynamic elastoplastic deformation is an important capability of DYNA3D. This paper presents an improved formulation for a 4-node quadrilateral shell element for explicit dynamic analysis. The proposed element is derived from a three-field weak form, and incorporates recently developed assumed strain methods for improved accuracy. In addition, the element is formulated in a large-displacement small-strain setting for minimum cost. Complex nonlinear constitutive models are easily incorporated into this formulation. Numerical examples illustrating the accuracy, robustness, and speed of the new element are shown. 13 refs., 3 tabs.