Partial Seismic Analysis - 'greyed out' structure is not editable

[ALJohns]

Hi Guys

I am considering a bridge crossing 4 rail lines.

In addition to standard loading (Dead, Live, Wind, Earthquake, Thermal etc.), I am considering a derailment case. The bridge has 2 central piers, and during the derailment case, it is assumed the central supports are compromised and the bridge spans across the 4 rail lines (with reduced live loading).

To analyse this, I have set up 2 similar models: The first is for checking all of the standard loads, the second is for checking the case with reduced supports (considering vertical loads only). My problem occurs when I set up seismic loads and define stories. I want to exclude the second model from seismic loading, but when I do, the second model is 'greyed-out' and is not editable (even for the standard load cases).

I have attached a screenshot with more details.

Thanks for your help.

Aaron.

[Artur.Kosakowski]

I suggest defining the models in the separate files.

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

[ALJohns]

Thank for the response Artur.

I was hoping to keep the two models in one file so that I can group similar members and run the steel verification and design for both models at the same time.

Can you explain the purpose of 'stories - advanced options' if it isn't used to isolate the extent of the seismic analysis?

Also, why is the structure 'greyed-out' for the standard load cases? Is this a bug, or is it indicating a modelling error?

Thanks for your help

Aaron

[Artur.Kosakowski]

Can you explain the purpose of 'stories - advanced options' if it isn't used to isolate the extent of the seismic analysis?

Could you attach the file? I initially assumed that you defined the response spectra analysis but perhaps you actually used the Equivalent Lateral Force Method instead? 

Also, why is the structure 'greyed-out' for the standard load cases? Is this a bug, or is it indicating a modelling error?

I assume you just have the story filer applied.