Dodd and Restrepo steel model - stl_dr

This is a uniaxial steel model initially programmed by Dodd and Restrepo [1995]. It considers the reduction of the unloading modulus with the plastic strain, whilst the reduction of the ultimate tensile strain is taken solely as a function of the maximum compressive strain, when the number of cycles is small enough to ignore the effects of low-cycle fatigue.

Eight model calibrating parameters must be defined in order to fully describe the mechanical characteristics of the material:

Modulus of elasticity - E
This is the initial elastic stiffness of the material. Its value usually oscillates between 200 and 210 GPa. The default value is 210 GPa.

Yield strength - fy
This is the stress at yield. Its value typically varies from 230 MPa up to 650 MPa. The default value is 295.4 MPa.

Stress at peak load
The default value is 479.5 MPa.

Strain at initiation of strain hardening curve
The default value is 0.016.

Strain at peak load
The default value is 0.207.

Strain of the intermediate point of the strain hardening curve
The default value is 0.053.

Stress of the intermediate point of the strain hardening curve
The default value is 420 MPa.

Specific weight -
This is the specific weight of the material. The default value is 78 kN/m3.