Lateral resistance of cold formed steel holddowns 1

[milkshakelake]

If I use a holddown with cold formed steel diagonal straps, there will be uplift and shear. The holddown schedules from Simpson only show tension/uplift capacity, not shear. How do I know if the shear is okay?

Wood is different because the plywood shear wall will take the shear and transfer it into the bottom plate, which can transfer it into the foundation with anchor bolts. I called Simpson about this but got bounced around between different "experts" so I'd rather ask here.

 

[XR250]

This is how I feel the gusset plate method plays out....

 

[milkshakelake]

@XR250 If it's stretching out like that, with weak axis and all, it doesn't really do anything in tension! Thanks for the tip.

 

[XR250]

I'd like to see to some testing to determine ho the loads are distributed.

 

[phamENG]

XR - this may be what you want...Link

Haven't read it myself, but I'm going to tuck it away for the next time I have some spare time...

 

[XR250]

Thanks Pham. Lots of stuff in there to make my brain hurt. Did not see the failure mode that I was anticipating. Seems like mostly strap failures and a an errant chord failure.

 

[r13]

XR250,

Similar to gusset plate in braced frame, the failure mode is to be prevented by design. If that's what you have in mind, this paper helps. Link