THE MODEL DEFORMS LATERALLY UNDER DEAD CASE !

[amghma]

Hi all
I have modeled a building of 4 stories and before defining load combinations and lateral load patterns ,the model behave normally under dead load, after defining earthquake patterns it deforms excessively in x and y...
I have attached a shot of deformed shape under Dead case, I would appreciate your opinions

 

[Agent666]

Can't really tell from the screenshot. What does the structural form look like and the deformed shape in 3d.

Are you missing a support perhaps?

 

[271828]

Are you sure the X and Y displacements, due to dead load, are changing when you add the earthquake pattern? ETABS might be changing the scale for drawing the displaced shape on the screen.

I'd try this:
1. Delete the earthquake load pattern.
2. Run the dead load case and write down the X and Y displacements at the center of the roof.
3. Add the earthquake load pattern.
4. Repeat #2.

 

[JasonMcKee71]

What is the value of discplacements?

Jason McKee
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