Wood shear wall supported by transfer beam 1

[jacky89]

Does anyone know how to calculate:

1) Deflection of the shear wall supported by a beam? What equation to use?

2) adequacy of beam to support shear wall? Do you just compare the shear wall moment (V * h) to the moment capacity of the beam?

Thanks!

 

[JoshPlumSE]

There are a number of aspects of design here:
1) Gravity load from shear wall to beam. Usually, I just look at this as a distributed load on the beam.
2) Shear transfer between wall and beam. I have to make sure the sheathing / nailing to the beam can handle this. I tend to design with Omega level forces for this as it is a point of discontinuity in the load path.
3) Hold down forces into the beam. You need to have to have some kind of mechanical strap or hold down to ensure this force transfer.
4) Overturning moment. I suppose if you've designed the hold downs to the beam then you could say that the moment transfer is handled. I think you also need to ensure that the beam-post connection can handle the uplift from the strap / hold down. You certainly don't want to use a pure hanger for cases where uplift due to overturning will be anticipated.

 

[jacky89]

Thanks for the response. I know how to connect the shear wall to the beam but just looking for the equations for calculation purpose per my OP.

 

[jayrod12]

I think that if you can't perform the analysis from Josh's description, you're likely not qualified to perform the analysis to begin with.

Perhaps talk to a senior designer in your office first?

 

[JoshPlumSE]

I think it's the additional deflection / drift at the top of the wall caused by beam rotation that is the main point of the original question. That is certainly a trickier concept.

I'd convert the wall moment into compression and tension at the post and hold down. Apply those as point loads to the beam. And, calculate the beam deflection from that. Then for the drift at the top of the wall due to this beam deflection, extrapolate that from the point load deflections at those two points.

Note: this would be pretty conservative. Because to a large degree, the shear wall will reduce the deflection in the beam.... That's just not something that we traditionally rely upon.