IBC/UBC Warning in My Canadian Seismic Load Model

Re: IBC/UBC Warning in My Canadian Seismic Load Model

Jack Xiao — Fri, 25 Oct 2013 03:28:15 GMT

Sorry, I opened another model which has PERFORM & CHANGE command and I mixed up the two similar models. Thank you very much!

Re: IBC/UBC Warning in My Canadian Seismic Load Model

Sye — Fri, 25 Oct 2013 02:26:27 GMT

I do get the warning message when I analyze the second file that you attached. Are you not getting the same ?

Re: IBC/UBC Warning in My Canadian Seismic Load Model

Jack Xiao — Thu, 24 Oct 2013 23:48:52 GMT

Thank you for your reply.

Before I posted this question, I tried to add PERFORM ANALYSIS & CHANGE after each seismic case in the last model and then the warning has gone. But, in another model (see attached) using NBCC generated seismic loads, even thought I don't have PERFORM ANALYSIS & CHANGE after seismic cases, that IBC/UBC warning does not appear. Does it make sense?

Re: IBC/UBC Warning in My Canadian Seismic Load Model

Sye — Thu, 24 Oct 2013 23:19:41 GMT

Although the warning message mentions UBC/IBC, it is applicable to seismic load generation as per any of the codes including the NBC of Canada. It is a generic warning and is provided whenever the software finds that an automatic seismic load generation has been used, irrespective of whether member tension/compression/REPEAT LOAD/MEMBER SELECTION has been used or not. In your case, since neither of these exist, you may simply ignore the warning. Else you may simply get rid of these warnings by adding the PERFORM ANALYSIS and CHANGE after each seismic case as shown next

LOAD 1 SEISMIC LOAD +X

************************************************************************************

NRC LOAD X 1

PERFORM ANALYSIS

CHANGE

************************************************************************************

LOAD 2 SEISMIC LOAD +Z

************************************************************************************

NRC LOAD Z 1

PERFORM ANALYSIS

CHANGE