Learning Forum

[BenjaminStarling]

nThe yes is currently in the MSUPkey position. this is the position that is required for future analysis that requires modal superposition. You can use Yes in the position you previously quoted, Elcalc, and this location, MSUPkey, defaults to yes. You will need to keep Elcalc set to yes, which I missed in my command.nIn regards to how this behaves when a subsequent analysis is run, I am not sure/familiar. An MSUP analysis uses the expansion results that are in the .mode file. This would imply that by limiting the modes that are expanded, that the MSUP analysis would use only these modes. I have never done this myself as I have never had a need to limit modes in such a way. I am not sure if a response spectrum analysis behaves the same way. My instinct is yes, that it will only use the modes written to the .mode file, which is controlled by the mxpand command, but I am not that familiar with response spectrum analysis. A quick test would be to run a simplified model, see if the mxpand command has an effect, and whether the spectrum response analysis uses the .mode file (try deleting the .mode file and see if it errors out).nIf this does not work, you will need to revisit the importance of acheiving high effective modal mass percentage.nn