CZone Crush Stress
The crush stress can be thought of as the stress of the crushing body at the crushing interface. The crush stress is specified as a material property but actually does not directly influence the constitutive calculations associated with element integration points; rather, the crush stress limits the contact pressure magnitude at an actively crushing interface as discussed in CZone Analysis.
The crush stress in the composite material can be a constant or can vary as a function of the angle, between the local x-direction of the crushable element and the contact normal direction projected to the plane of the element.
Crush Stress as a Function of a Field Variable
The crush stress in the composite material can vary as a function of a predefined field variable. This field variable can represent any physical or geometrical quantity that might affect the crush stress, such as curvature of the laminate.
Crush Stress as a Function of Velocity
The crush stress in the composite material can depend on the deformation rate at the crush front. The crush stress velocity factor is used to scale the crush stress based upon velocity. The scaling factor is calculated from a user-supplied table of scaling factor versus relative surface velocity.
The final crush stress is the velocity dependence factor multiplied by the original crush stress. No extrapolation of the supplied data is performed for velocities that lie outside the maximum or minimum value supplied, as shown in Figure 1.
