Accession Number : ADA295626

Title :   Developments in the Explicit Derivation of Hybrid Stress Finite Element Matrices.

Descriptive Note : Final rept. Jan-Mar 95,

Corporate Author : ARMY RESEARCH LAB WATERTOWN MA MATERIALS DIRECTORATE

Personal Author(s) : Saether, Erik

PDF Url : ADA295626

Report Date : MAR 1995

Pagination or Media Count : 29

Abstract : A general methodology for deriving explicit element stiffness matrices in hybrid stress 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)

Descriptors :   *STRESS ANALYSIS, *FINITE ELEMENT ANALYSIS, STRESS STRAIN RELATIONS, MATHEMATICAL MODELS, OPTIMIZATION, COMPUTATIONS, MATRICES(MATHEMATICS), STIFFNESS, ELASTIC PROPERTIES, CONTINUUM MECHANICS, NUMERICAL INTEGRATION, INTERPOLATION, HYBRID SYSTEMS, NONLINEAR ANALYSIS, FORMULAS(MATHEMATICS), CANTILEVER BEAMS, ALGEBRAIC FUNCTIONS.

Subject Categories : Numerical Mathematics
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE