I want to calculate the Story Drift corresponding to a Response Spectrum Load Case. But I encounter the following error message.
WARNING: THE LOAD# 11 IS AN 1893 RESPONSE SPECTRUM LOAD CASE. STORY DRIFT IS NOT CALCULATED. THE STORY DRIFT WILL BE CALCULATED FOR INDIVIDUAL MODAL RESPONSE LOAD CASES.

You have used the “PRINT STOREY DRIFT” command, which does not work with the Response Spectrum Load Cases (or Time History Load cases). This will work for all other load cases including the static seismic load cases.

For Response Spectrum Cases, this command will only work if you apply it on individual modal load cases.

However, currently you can use the CHECK STOREY DRIFT command after the Response Spectrum Load Cases which will calculate the Storey Drift for the Response Spectrum Load Cases. For more details on this command, please refer to section AD.2007-09.2.4 Check Story Drift of the help file.