# Stress Strain Relationships
The relationship between stress and strain depends on the type of problem
| Problem | Displacements | Strain | Stress |
|---|---|---|---|
| Plane stress | |||
| Plane strain | |||
| Axisymmetric | |||
| Plate Bending | |||
| General |
Where for beam and plate bending problems the relationship is between moment and curvature
The stress-strain matrices for isotropic materials are
| Problem | Stress-strain matrix |
|---|---|
| Plane stress | |
| Plane strain | |
| Axisymmetric | |
| Plate bending | |
| General |
The stress-strain matrices for orthotropic materials:
| Problem | Stress-strain matrix |
|---|---|
| Plane stress | |
| Plane strain | |
| Axisymmetric | |
| Plate bending | |
| General |