Pipe pile response in soil

[mlw]

Hi all,

I have been comparing the OpenSees pile bending moments against case history data for seismic shaking table and centrifuge experiments. I have compared 4 case histories.
What I am finding is that OpenSees seems to underpredict pile bending moments of the thin walled pipe piles, but has no problem with thick walled pipe piles and solid piles.

I am using the elasticBeamColumn pile materaial, and have attached my pile to the surrounding soil elements by other elasticBeamColumnElements, similar to the pile and rigid-link combination employed in OpenSeesPL.

I have also been in contact with another postgrad student who is using OpenSees for his research, and he has found the same problem.

Has anyone else encountered this prolem - and how was it fixed?
Or could it be that the pile and rigid-link combination is not capturing the pile response during earthquake shaking?

mlw