Orthotropic Plastic Softening Material
Constitutive Law
This MPM softening material is an orthotropic, elastic-plastic material that can also develop anisotropic damage. In the absence of damage, this material is identical to a Anisotropic, Elastic-Plastic Material. In the absence of plasticity, this material is identical to an Orthotropic Softening Material. If conditions allow, the material can develop both plasticity and damage with softening. Note that if plastic yield properties are below damage initiation stress, the material may never reach stress to cause damage. But, if the plastic properties allow hardening, the material can yield first and then start damage after hardening allows stresses to reach stress for initiation of damage.
Material Properties
For material properties, combine all options available for an Anisotropic, Elastic-Plastic Material and for an Orthotropic Softening Material. This material must, however, use large rotation mode.
| Property | Description | Units | Default |
|---|---|---|---|
| (Orthotropic Properties) | Enter all properties needed to define the underlying orthotropic material response | varies | varies |
| (Orthotropic, Plastic Properties) | Enter orthotropic yield properties | varies | varies |
| (Orthotropic Softening Properties) | Enter properties for initiation of damage and for two softening laws | varies | varies |
| (other) | Properties common to all materials and must use the large rotation option | varies | varies |
History Variables
The plasticity modeling for this material uses one history variable and will start with history variable number 1. After that variable, the remaining variables will be for the Orthotropic Softening Material material. Because plastic strain is used for plasticity, three additional history variables (compared to Orthotropic Softening Material) track the three components of cracking strains in the crack axis system corresponding to normal and shear crack opening displacements.
Let S be number of history variables for damage needed by an Orthotropic Softening Material, respectively. The history variables for this material are then:
- 1: Plastic law history variable
- 2 to 1+S: Orthotropic Softening Material history variable S
- 2+S: εc,xx or x direction cracking strain normal to crack in the crack axis system
- 3+S: γc,xy or x-y direction shear cracking strain in the crack axis system
- 4+S: γc,xz or x-z direction shear cracking strain in the crack axis system
This material also tracks plastic strain which can be saved by using the plasticstrain archiving option. The total plastic is archived in the global axis system.
If you also archive the damagenormal, you will be able to plot a vector along the crack-opening displacement vector in the crack axis system.