PLASTIC STRESS-STRAIN MATRIX AND ITS APPLICATION FOR SOLUTION OF ELASTIC-PLASTIC PROBLEMS BY FINITE ELEMENT METHOD

A method is proposed for the solution of the continuum elastic-plastic problems by means of the finite element approach. The method is based on a plastic stress-strain matrix which is derivable by inverting the Prandtl-Reuss equations in plasticity theory. The matrix is of quite simple form and facilitates the incremental treatment of elastic-plastic problems. The present approach follows the indication of Marcal and King's work, but uses the small and varying increments of load sufficient to just cause yield in the successive elements, the continuum being divided into triangular elements. As examples of solutions notched tension specimens under conditions of plane stress are studied. © 1968.