Developments in the Explicit Derivation of Hybrid Stress Finite Element Matrices

摘要

A general methodology for deriving explicit element stiffness matrices in hybridstress formulations has recently been developed by the author. The technique utilizes special stress field transformations to eliminate the complementary energy matrix inherent to hybrid formulations, thus simplifying the constituent matrices such that an explicit evaluation can be accomplished. The elimination of numerical integration and matrix inversions result in a substantial decrease in computational cost. The methodology is demonstrated by deriving explicit algebraic expressions for the Pian-Tong hexahedral element stiffness matrix and in the development of an explicit form of the Pian-Sumihara quadrilateral element incorporating nonconstant material properties for nonlinear-elastic analyses. (AN).