I am working on a project with irregular loading on Etabs. It is just a simple model at the moment, with just gravity loading and seimic loading. I made a load combination of the two loading and run an analysis. I noticed that if I varied the loading it had no impact on the story drift, which makes me think that Etabs is not analysising the effect of the dead+seimic together. Any ideas in what I am doing wrong?
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Etabs: Irregular Loading Etbs
- Thread starter Meekis
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slickdeals
Structural
That's not possible. Do you have the right mass source chosen?
- Thread starter
- #3
jdgengineer
Structural
It's under define --> mass source. The mass source is what the program uses when calculating seismic forces.
johnbridge231
Civil/Environmental
If the a load that is included in the mass source is changed, the stiffness of the building is modified accordingly, so the drifts will change.
Otherwise, no effect on story drifts will take place.
Analysis and Design of arbitrary cross sections
Reinforcement design to all major codes
Moment Curvature analysis
Otherwise, no effect on story drifts will take place.
Analysis and Design of arbitrary cross sections
Reinforcement design to all major codes
Moment Curvature analysis
slickdeals
Structural
@john,
The stiffness of the building is independent from the mass. However, the building's time period depends on both mass and stiffness. Higher the time period - lower the seismic forces.
The stiffness of the building is independent from the mass. However, the building's time period depends on both mass and stiffness. Higher the time period - lower the seismic forces.
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