Quadrilinear asymmetric curve - quad_asm

This is a curve employed to model idealised quadrilinear behaviour. An isotropic hardening rule is adopted and ten parameters need to be defined in order to fully characterise this response curve:

Yielding strength for positive loading direction (F_y(+))
The default value is 500

Yielding displacement for positive loading direction (d_y(+))
The default value is 0.005

Ultimate strength for positive loading direction (Fu₍₊₎)
The default value is 550

Ultimate displacement for positive loading direction (du₍₊₎)
The default value is 0.02

Residual strength for positive loading direction (+)
The default value is 200

Yielding strength for negative loading direction (F_y(-))
The default value is 400(-)

Yielding displacement for negative loading direction (d_y(-))
The default value is 0.005(-)

Ultimate strength for negative loading direction (Fu_(-))
The default value is 450(-)

Ultimate displacement for negative loading direction (du_(-))
The default value is 0.02(-)

Residual strength for negative loading direction (-)
The default value is 200(-)