4.2 Nonlinear Elasticity

Nonlinear elasticity sets a unique nonlinear relation between stress and strain. The behavior for loading and unloading is the same. A uniaxial nonlinear stress-strain diagram may be input for beam and truss elements. Application of nonlinear elasticity in combination with other material models is restricted by the following.

• Nonlinear elasticity cannot be applied in combination with cracking or temperature influence.

• Except for the Boyce and the Jardine model, the nonlinear elasticity models described in this section cannot be applied in combination with plasticity.

• Special nonlinear elasticity models are available that could be combined with the Egg Cam-clay [§5.1.4] and the Modified Mohr-Coulomb [§5.1.5] plasticity models.