hookeai.miscellaneous.materials.plot_yield_surface.yf_lou_zhang_yoon

yf_lou_zhang_yoon(s1, s2, s3, sy, model_parameters)[source]

Yield function: Lou-Zhang-Yoon model with isotropic strain hardening.

Parameters:

  • s1 (float) – First principal stress.

  • s2 (float) – Second principal stress.

  • s3 (float) – Third principal stress.

  • sy (float) – Yield stress.

  • model_parameters (dict) – Constitutive model parameters required to compute yield function.

Returns:

phi – Yield function value.

Return type:

float