4.13.1.1. Steel01¶

uniaxialMaterial('Steel01', matTag, Fy, E0, b, a1, a2, a3, a4)

This command is used to construct a uniaxial bilinear steel material object with kinematic hardening and optional isotropic hardening described by a non-linear evolution equation (REF: Fedeas).

`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)
`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)

Note

If strain-hardening ratio is zero and you do not expect softening of your system use BandSPD solver.