UNIFIED FORMULA OF MATRIX H CORRESPONDING TO SEVERAL YIELD CRITERIA IN ELASTO-VISCOPLASTIC FINITE ELEMENT ANALYSIS

Reference 1 intruduced numerical method of elasto-viscoplastic finite element solution and presented expression of matrix H for the Mises criterion. In this paper, the author derives the unified formula of matrix H for the four yield criteria, i.e., Mises, Tresca, Mohr-Coulomb and Drucker-Prager which are often appeared in engineering, discusses method of eliminating singularity in Tresca or Mohr-Coulomb criterion, and obtains corresponing formula.