Pile lateral loading in SANISANDS

[jiangtaolei]

Dear stkoteam,
I am trying to model pile lateral loading using sanisand soil.
Both soil and pile are modelled as SPP brick elements. Pile material was set as elastic with the physical parameter of steel. pile inner diameter was connected to the central node at mudline through elastic beams, pile upper structure was modelled as Timoshenko beam and connected to the central node.

I found the shape of simulated pile lateral loading curve is different from that simulated in Plaxis (also the one calibrated for a centrifuge tests), which is quite similar to the problem raised in this post: viewtopic.php?t=3312&start=10

and the plastic effect of the sanisand model seems quite limit in opensees simulations.

I attach the scd files and some figures here, could you help to check if I implement some thing wrong in the model?/

[STKO Team]

Try this and see what I changed

[jiangtaolei]

Very many thanks for checking the model, but when I am trying to run it, the following errors appeared see attached.

I use opensees (0) and the version of opensees is 3.7.2 64 bit.


could u please tell me whats wrong with it?
Thanks!!!!

[jiangtaolei]

By the way, our STKO version is 4.0.0

[jiangtaolei]

I found the reason is because the shear modulus of rigid link and pile beam was set as zero in the modified model. so I change it to that of steel and the model can be run properly.

I noticed the node force was set as a target lateral displacement, but for analysis step: pile lateral loading, it is still force control, not sure if it is proper.

I checked the simulation results(attached1) using reaction force at mudline, it seems the curve still quite linear, I then set the target displacement as 2m, but the curve still looks linear and not like the sanisand model curve （attached2）. would it be possible to check again whats wrong with the model? Also, how can I plot force-disp curve at pile top if displacement control is used?

Regards

[jiangtaolei]

Dear STKO team,

I have not received any updates on this issue.

would it be possible to follow up the issue I encountered?

Thank you so much!

[STKO Team]

you should attach your updated file for us to check