https://opensees.berkeley.edu/wiki/inde ... _Material)
How to calibrate them?
Well, there is no specific rule. First, you have to understand what they mean in the numerical model (see the link above). Finally, you have to calibrate them according to what you want to simulate.
In your case, the shear behavior of an RC column.
They define the pinching of the hysteresis loop. You need some cyclic experimental tests to calibrate them. Otherwise use the values we used in our webinar.$FprPos (You have considered 0.4 in your e-learning tutorial)
$A_Pinch (You have considered 0.1 in your e-learning tutorial)
They are necessary to define cyclic deterioration. In our tutorial we did not have any data to calibrate them, so we did not consider cyclic deterioration.$Lamda_S (You have considered 0 in your e-learning tutorial)
$Lamda_C (You have considered 0 in your e-learning tutorial)
$Lamda_A (You have considered 0 in your e-learning tutorial)
$Lamda_K (You have considered 0 in your e-learning tutorial)
$D_Plus (You have considered 0 in your e-learning tutorial)
It defines how large is the final residual strength$Res_Pos (You have considered 1.05 in your e-learning tutorial)
It defines at what abscissa your residual strength drops to zero. In our case we did not want it to drop to zero, that's why we used a very large value$theta_u_Plus (You have considered 100 in your e-learning tutorial)