Questin about DispBeamColumn and ForceBeamColumn

[foadEng]

Hi
I want to ask a question about the differences between these 2 commands : "element nonlinearBeamColumn" and "element dispBeamColumn" ? I can't really understand how each of these commands can effect pushover analysis?
thanks!

[fmk]

the two commands generate two different nonlinear beam column elements .. one is force based and the other is displacement based .. i suggest you look at the papers given in the command manual as references for the nonlinearBeamColumn element (also known as forceBeamColumn) to learn more.

[fmk]

the displacement beam is just your standard beam element found in any nonlinear code .. it assumes linear curvature over length and constant axial strain .. standard finite element integration is used.

[linguan118]

I found from the source code that nonlinearbeamelement is just directed to the code of forcebeamelement. I don't know if there was any intended difference between the two?

[fmk]

there was no intended difference, the person who wrote the original forceBeamColumn used the name nonlinearBEamColumn in the element command .. when the displacement beam came along we redid the options in the ele command, one for dispBeamColumn and the other for forceBeamColumn .. the nonlinearBeamColumn stuck around for backward compatability, i.e. to keep old scripts running .. the command manual only has force or disp options.