# Isotropic3D

## General description

Constitutive law, that calculates the stresses from given strains according to Hooke's law.

## Constitutive Matrix

$\boldsymbol{C}=\left[\begin{array}{cccccc}2G+\lambda&\lambda&\lambda&0&0&0\\\lambda&2G+\lambda&\lambda&0&0&0\\\lambda&\lambda&2G+\lambda&0&0&0\\0&0&0&G&0&0\\0&0&0&0&G&0\\0&0&0&0&0&G\end{array}\right]$ with: $\lambda=\frac{E\nu}{\left(1+\nu\right)\left(1-2\nu\right)}$ and $G=\frac{E}{2\left(1+\nu\right)}$

## How to use this constitutive law

Assign for Isotropic3D to the constitutive law in the respective properties (self.model_part.Properties[1].SetValue(CONSTITUTIVE_LAW, Isotropic3D() )).