Formulation of Stiffness Equation for a Three-Dimensional Isoparametric Element with Elastic-Plastic Material and Large Deformation.

摘要

The formulation of the stiffness equation for an 8to 21node isoparametric element with elastic-plastic material and large deformation is presented. The formulation has been implemented in a nonlinear finite element program for the analysis of three-dimensional continuums. To demonstrate the utility of the formulation, a thick-walled cylinder was analyzed and the results are compared favorably with a known solution. The element type presented can be applied not only to 3-D continuums,but also to plate or shell structures,for which degenerated isoparametric elements may be used.