Thank you for you note regarding to soil elements.
Your question about contact is so general! Could you please be more specific so I may help you. I have modeled a very few contact problems and I ran into many problems; some of them I worked them out and I am still working on the others.
I would to state my problem more clearly. I would like to do a pull-out analysis of suction caisson in clay to find the limit load; therefore, I need to do finite sliding analysis. I have tried to use surface to surface contact and apply surface friction coefficient equal to 0.6 (independent of contact pressure). However, when I compare with the result without using any interface contact (caisson and soil share same nodes). The results are almost the same. I'm not sure whether something wrong in my command or I choose wrong type of contact.
Hi,
I am working on as similar problem; determine the dynamic properties for soil nails by applying Impulse-Response technique. In order to model the contact between the soil and the nail, I started with a very simple case. I modelled the contact between the soil and a steel rod by itself using Gap element. The results were identical to the ones obtained by experimental procedures.
In the model, I did not define any kind of friction coefficient since I am not I applying a pullout force; the force I am using is very small in amplitude.
I have a doubt that using Gap element in a lateral direction sounds strange, but the results I am getting are promising.
So, as for your problem, I would say use Gap element as a contact element in the lateral direction with defining coefficient of friction and use Gap element as well to model the gap opening at the foot ending due to pull out load.
