Gravity Analysis of Soil Column
Posted: Thu Feb 05, 2026 7:47 pm
Dear STKO Team,
I am attempting to run an analysis on a soil column by applying seismic waves. But firstly, I need to run a gravity analysis (both plastic and elastic). However, my simulation only converges when the value in the z-direction for volume force (self weight of the soil) is very low, otherwise the soil column starts falling.
I am fixing the base of the soil column vertically and using equal DOF for nodes that are at the same height vertically. I am using the volume force as the soil self weight. I am using the updateMaterialStage command to update the soil from elastic to plastic. I am using the PIMY soil material model. I am using a total of 10 soil layers stacked on top of each other.
Please may you advise on what is wrong with my model, which I have attached.
Thanks,
Matthew
I am attempting to run an analysis on a soil column by applying seismic waves. But firstly, I need to run a gravity analysis (both plastic and elastic). However, my simulation only converges when the value in the z-direction for volume force (self weight of the soil) is very low, otherwise the soil column starts falling.
I am fixing the base of the soil column vertically and using equal DOF for nodes that are at the same height vertically. I am using the volume force as the soil self weight. I am using the updateMaterialStage command to update the soil from elastic to plastic. I am using the PIMY soil material model. I am using a total of 10 soil layers stacked on top of each other.
Please may you advise on what is wrong with my model, which I have attached.
Thanks,
Matthew