Obtaining stress invariants, principal stress/strain values and directions, and rotating tensors in an Abaqus/Standard analysis

Utility routines are available for calculating stress invariants, principal stress/strain values, and principal stress/strain directions from the relevant tensors, as well as for transforming tensors to a new basis.

These utility routines are available for Abaqus/Standard user subroutines that store stress and strain components according to the convention presented in Conventions. They are most commonly called from user subroutine UMAT.

The following topics are discussed:

Related Topics
In Other Guides
Calculation of principal stresses and strains and their directions: FPRIN