ETABS_Seismic Load pattern

[melsawaf]

Dears

I`m using ETABS 16 and defining EQ load pattern as shown in attached photo (6 steps), My question is how ETABS deal with this MULTI STEPS - load pattern in combination like ( 0.9D + 1.0 E).

 

[Agent666]

Do it and see? The E case defined like that will create 6 separate cases. Can't remember what happens when you use that case in a load combination. Just try it and you'll see what it does.

You're often better defining two separate cases for X and Y directions because you might need to have X and Y combined in a single combination like 100%X + 30%Y.

 

[Trenno]

I think ETABS creates various 'steps' within that particular load case.

Agree with Agent666 - it's best to break seismic cases down to their basic minimum. Makes it much easier to debug, visualise and combine the loads down the line.

 

[melsawaf]

thanks all for your replies