Do Drag transfer connections need to resist tension & compression?

[reverbz]

Hey Guys,

I'm designing a truss as a drag member in my diaphragm. It's connected along a shearwall to the top chord of the truss w/a34's. It runs into a wall that separates it from another truss aligned with it on the other side. I was going to add a Simpson cs16 to transfer the drag load but that only resist tension. I was thinking that compression is already naturally transferred through the wall. Is that correct or do I need to add a T/C strap instead of a CS?

Thank you!

 

[driftLimiter]

In most cases the drag load is reversible. Or at least there is a value for both tension and compression loads.

"Naturally transferred through the wall" is not a means of load transfer.

Options are bearing or mechanical connectors (direct or shear) as a means of transferring compression. Perhaps others but these I think are most common.

The detail you use at the connection should dictate which load path you have evaluated to transfer the compressive force.

Its hard for me to picture what detail you are describing, but in summary you should have a detailed load path for both tension and compression load transfer into the shear walls.

 

[lexpatrie]

You really need an image here. Try adding a sketch to your original post with the photo icon and the word "image". It accepts jpegs, but not PDFs, (other image types might work, you'll have to test it).

Compression would at least sometimes be transferred via bearing on the end (of the top chord) so it's not a strap you're after, it's a rational analysis of the compression load in the strut and proving it works based on whatever bracing is present. I would say for relatively normal cases, the compression case won't control, unless it's asymmetrical and the compression load is higher, or something atypical is going on (no bracing, no plywood, etc.)