Hello All,
I am currently working on modifications of a tower structure with existing deep piles. The modifications require new drilled shafts to be added to the foundation to support the additional loads.
To account for the dead load already in the existing piles, I have made the new shafts INACTIVE MEMBERS with a CHANGE command after the dead loads are run.
Currently, I have the shafts modeled as COMPRESSION MEMBERS with supports at the bottom as FIXED BUT without moment about the Y and KFY as the estimated stiffness. Along with this I also have a SPRING COMPRESSION command at these supports in the KFY. Both of these commands directly follow the CHANGE command.
The issue I am having is that once I run the analysis and check the Beam End Force Summary, I am still seeing large tension magnitudes.
I have a feeling it has something to do with my change command but I am not sure. I have checked other relevant threads but the advice did not work for my model. Any advice on how to get the tension in these piles to significantly reduce would be greatly appreciated. Thank you.