One shear wall for entire building?

[faromic80]

I have a building about 100 feet wide and 80 long. It's one story steel frame with masonry wall running down center in short direction. i don't have masonry at edges and want to use just the center masonry wall to resist shear. how would the shear from the diaphragm transfer into the wall? would the diaphragm act as a cantilever from the wall to the edge of the building in both directions?

 

[NKT]

You need at least three lines of shearwalls (or other lateral-force-resisting elements) to provide resistance against torsion...

 

[msquared48]

I have seen this done, but my preofessional opinion is that it leaves no redundancy for the structure should that element fail. Consequently, I would neverdo it.

Mike McCann
MMC Engineering

 

[jike]

I agree with NKT. Provide a minimum of 3 lines of bracing, frames or shear walls.

 

[faromic80]

That's what I thought. one shearwall doesn't seem like a smart idea

 

[DaveAtkins]

This reminds me of the mini storage buildings I have designed. In the long direction, there is one shear wall down the middle. But you have lots of transverse shear walls to take care on any accidental torsion.

On your building, you must have some lateral resisting elements in the short direction, so what are you concerned about?

DaveAtkins

 

[csd72]

faromic80,

As noted above, this can be done, but there needs to be at least 2 in the perpendicualr direction to take out torsion.

As noted, having only one shear wall means no redundancy, so I would make sure that you have considerably more capacity in that wall than you need (say 150%).


also note that the maximum moment in the diaphragm is at the shear wall, so make sure this is adequate.

 

[tngolfer]

I assume you are using 1.5" B-type roof deck. I don't believe this can be considered rigid. Make sure the diaphragm values are sufficient since all of the shear load will be going through one connection.

Another option, since you have a steel frame, can you run the beams over the columns and count on some frame action in addition to the shear wall - like a dual system? If the members are there anyways, why not use them?

 

[tngolfer]

One last thing, IBC refers to 9.5.2.4 of ASCE 7. It has to do with REDUNDANCY. If you are under IBC, make sure you meet all of the requirements. If not, it is a good reference.