**process evcum_sum

Description

This post-processing computes the equivalent plastic strain of two plastic strain tensors \(\ten \varepsilon^{v_1}\) and \(\ten \varepsilon^{v_2}\), e.g., for a material with two visco-plastic potentials.

\[\varepsilon_{eq} = \sqrt{\dfrac{2}{3}\left(\ten \varepsilon^{v_1}+\ten \varepsilon^{v_2}\right):\left( \ten \varepsilon^{v_1}+\ten \varepsilon^{v_2}\right)}\]

Syntax

**process evcum_sum \(~\,\) *strain_tensor_1 strain1 \(~\,\) *strain_tensor_2 strain2

where strain1 and strain2 are strain tensors.

Output: equivalent plastic strain ev_eq.

Example

***local_post_processing
 **file integ
 **elset ALL_ELEMENT
 **process evcum_sum
  *strain_tensor_1 epi
  *strain_tensor_2 evi