Description: User subroutine VUMULLINS can be used to define the damage variable associated with Mullins effect in Abaqus/Explicit. This feature provides functionality equivalent to user subroutine UMULLINS in Abaqus/Standard. The feature complements the two other available methods for defining damage; namely, direct specification of damage material parameters or specification of test data. The damage can be defined in terms of any number of user-defined constants. The subroutine also provides users with access to solution-dependent state variables as well as temperature and field variables. In addition to defining the damage variable, the user can also define the strain energy dissipation due to damage as well as a criterion for material failure.