Lateral load on joist to joist connection 1

[compe_ad]

Hi all! I am trying to understand the diaphragm behavior for bare steel deck supported by joist (let's say at 6 ft o.c) on perpendicular direction. I think when structure is laterally loaded, deck should be provided with sufficient shear strength to resist the shear stress generated on diaphragm due to lateral load. I believe joist doesn't see any considerable axial loads due to the exerted lateral loading. The reason for this is the out of plane stiffness of walls are negligible and do not create restrain for the joists. So, the only major force that need to be transmitted between the joist to joist is the anchorage force that ASCE 12.11.2.2.2. Please correct me if my understanding is wrong.

 

[DaveAtkins]

I agree that typically engineers do not concern themselves with the additional axial load in the joist from the lateral load. Depending on the detailing, there probably will be some axial force, but it is typically ignored.

DaveAtkins

 

[Althalus]

I'm interpreting SDI deck on SJI joists. Correct?

The diaphragm's function is to transfer the forces to the parallel edges (in this case, the short walls). This will include the attachment of the joists to the deck. You heard that right, joists to deck, not deck to joist.

The joist doesn't transfer the lateral load to the longitudinal walls. The joists seismic load is transferred to the deck via the deck's connections (welds or screws). Then the diaphragm acts as a horizontal beam that distributes the lateral load to the transverse (the shorter sides) shearwalls.

 

[compe_ad]

Thanks all!
@Athalus-> I heard this for the first time. If force is transferred for joist to deck does the deck has enough shear capacity in the direction perpendicular to the ribs to withstand the diaphragm shear generated?
Can you please provide reference to this concept if you know any?