ExpJ2

Exponential Isotropic Hardening J2 Model

The kinematic hardening is not defined in this model.

Theory

The backbone function is defined as

$$\sigma ={\sigma }_y((1+a)e^{-b{\epsilon }_p}-a{e}^{-2b{\epsilon }_p}),$$

where $a$ and $b$ are two constants that control the shape of the backbone. The initial stiffness ${\sigma }^{\prime }{|}_{{\epsilon }_p=0}={\sigma }_y(a-1)b$.

Syntax

material ExpJ2 (1) (2) (3) (4) (5) (6) [7]
# (1) int, unique material tag
# (2) double, elastic modulus
# (3) double, poissons ratio
# (4) double, yield stress
# (5) double, a
# (6) double, b
# [7] double, density, default: 0.0