This law is only used with solid brick and quadrilateral elements.
It models the elastic and plastic regions, similar to LAW2, with a nonlinear behavior of
pressure and without strain rate effect. The law is designed to simulate materials in
compression.
The stress-strain relationship for the material under tension is:
The pressure and energy values are obtained by solving equation of state related to the material (/EOS).
Input requires Young's or the elastic modulus, , and Poisson's ratio, . These quantities are used only for the deviatoric part. The
plasticity material parameters are:
Yield stress
Hardening modulus
Hardening exponent
Maximum flow stress
Plastic strain at rupture
A pressure cut off, Pmin, can be given to limit the pressure in tension. The pressure cut off must be lower or
equal to zero. Figure 1 shows a typical curve of the
hydrodynamic pressure.Figure 1. Hydrodynamic Pressure Relationship