Hi Mr. Peterrozenewman,

Thanks  a million for your answers.

First of all of if the max. penetration in a really small point is 0,066, is it acceptable?

1) Updating Normal Stiffness:

As you said Updating Stiffness is the recommended option. But I want to know what does Ansys do exactly in this option? Because of convergence problem I selected Normal Stiffness=0,1, then by activating Updating Normal Stiffness in each iteration, how does Ansys solve problem?

And as I understood Updating Stiffness increases solution time to reduce penetrations as much as possible, but if it is inactive the model could be solved but with some penetrations (if K value is small). Then we need to check the final penetration contour to see whether penetration values are acceptable or not. am I right?

2) About contact detection method:

I checked all options to see the effect of them on the results. As you can see in the picture the left side of load applicator has edge-surface contact with the structure because of a fracture plane which slices the contact surface in two parts with an offset. So, when I selected Nodal-Normal-Target Method, displacement of loading center is close to the experimental values. However, selecting one of 4 other options results 20% error in estimating displacement of loading center. So, I do not know why should it happen, and how can I select the best contact detection method?

3) Regarding Interface Treatment:

If I select adjust to touch or add offset (no ramp), displacement of loading point is different. Adjust to touch options results in an accurate value which is close to experimental one. However, the result of add offset option is really far from the experiment. So, because of that I do not know which option could be more accurate and reasonable to select.

I really would be grateful for your advice in advance.

Best regards