ComputeLagrangianStressPK1

Overview

This class provides an interface to define a constitutive model in terms of the 1st Piola-Kirchhoff stress and the associated algorithmic tangent See here for a complete description of the Lagrangian kernel material system and for detailed instructions on how to implement a new material model.

Conversion

This class converts the 1st Piola Kirchhoff stress and the algorithmic tangent to provide the Cauchy stress, where needed by the Lagrangian kernel system. The conversion formula are and