# Damage properties

User material models can be combined with the `*PROP_DAMAGE_[XXXX]` commands, enabling the use of the build-in damage failure criterion models. This feature is ideal if one want to use well known and defined damage models.

When a damage ID is specified, our software automatically uses the built-in implementation. The only requirements are that the positions of certain properties are defined. Some the variables, such as `pos_epsp` and `pos_temp` are overlapping with "Material properties". They are used for multiple purposes.

## Class member variables

     int pos_epsp
     int pos_depsp
     int pos_rate
     int pos_temp
     int pos_evol
     int pos_damage1
     int pos_damage2

## Description

    int pos_epsp

Location of `epsp` in the state variables array.

    int pos_depsp

Location of `depsp` in the state variables array.

    int pos_rate

Location of `rate` in the state variables array.

    int pos_temp

Location of `temp` in the state variables array.

    int pos_evol

Location of `evol` in the state variables array.

    int pos_damage1

Location of `damage1` in the state variables array.

    int pos_damage2

Location of `damage2` in the state variables array.