<CRITERION> tensile_mises

Description

This is a criterion which acts as a von Mises yield if the trace of the effective stress (e.g. \(\ten \sigma-\sum\ten X_i\)) is greater than zero. If it is less than zero, the criterion will never yield.

(368)\[\begin{split}\begin{aligned} &f_{cr} = \left[\frac{3}{2}\hat{\ten \sigma}:\hat{\ten \sigma}\right]^{0.5} - R\qquad &\trace{\ten \sigma}\ge 0 \\ &f_{cr} = 0 &\text{otherwise} \\ \end{aligned}\end{split}\]