# Vertical Irregularity



## MOOK (Jul 25, 2010)

If you have 4 story building, the building has shear walls in the upper 3 stories but it does not have one i the first story. Do you consider this Vertical Irregularity Type (4) or not?


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## parthurvt (Jul 26, 2010)

MOOK said:


> If you have 4 story building, the building has shear walls in the upper 3 stories but it does not have one i the first story. Do you consider this Vertical Irregularity Type (4) or not?


I think I would consider that a Type 1b Vertical Irregularity - Extreme Soft Story. Type 4 would be if there was a shear wall in the first story but located in a different place.


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## MOOK (Jul 26, 2010)

parthurvt said:


> MOOK said:
> 
> 
> > If you have 4 story building, the building has shear walls in the upper 3 stories but it does not have one i the first story. Do you consider this Vertical Irregularity Type (4) or not?
> ...


Well, Vertical Irregularity type (4) also exists if there is change in stiffness between stories. Can not we consider that the stiffness in the first story became = zero and as a result, consider it vertical irregularity type (4).

I am saying this because I am trying to figure out why some text books consider it vertical irregularity type (4).

Thanks


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## parthurvt (Jul 27, 2010)

MOOK said:


> parthurvt said:
> 
> 
> > MOOK said:
> ...


That's strange about the textbooks, I guess you could consider it a type (4) since there is a reduction in stiffness. However I do still maintain that 1b fits this particular situation more closely.


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## greatjohn (Aug 1, 2010)

Irregularity 4 may apply. since Type 1 and 5 actually are judged based on the contribution of the whole story.


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## MOOK (Aug 1, 2010)

Good point


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