4.14.1.2. Steel02ΒΆ

uniaxialMaterial('Steel02', matTag, Fy, E0, b, *params, a1=a2*Fy/E0, a2=1.0, a3=a4*Fy/E0, a4=1.0, sigInit=0.0)

This command is used to construct a uniaxial Giuffre-Menegotto-Pinto steel material object with isotropic strain hardening.

matTag (int) integer tag identifying material
Fy (float) yield strength
E0 (float) initial elastic tangent
b (float) strain-hardening ratio (ratio between post-yield tangent and initial elastic tangent)
params (list (float)) parameters to control the transition from elastic to plastic branches. params=[R0,cR1,cR2]. Recommended values: R0=between 10 and 20, cR1=0.925, cR2=0.15
a1 (float) isotropic hardening parameter, increase of compression yield envelope as proportion of yield strength after a plastic strain of \(a_2*(F_y/E_0)\) (optional)
a2 (float) isotropic hardening parameter (see explanation under a1). (optional).
a3 (float) isotropic hardening parameter, increase of tension yield envelope as proportion of yield strength after a plastic strain of \(a_4*(F_y/E_0)\). (optional)
a4 (float) isotropic hardening parameter (see explanation under a3). (optional)
sigInit (float)

Initial Stress Value (optional, default: 0.0) the strain is calculated from epsP=sigInit/E

if (sigInit!= 0.0) {
  double epsInit = sigInit/E;
  eps = trialStrain+epsInit;
} else {
  eps = trialStrain;
}

See also

Steel02