Minimum numer of bolts for bracing connection (Canadian code CSA S16)

[ghcaste]

Hello,

I am reviewing some drawings with steel bolted connections. The are some lateral bracings bloted on each end with one bolt. Does anyone know if there is any requirement about minimum number of bolts to place on a connection? A tech in my office says it should be at least 2 bolts, but I cannot find this requirement on the code.

 

[connectegr]

A single bolt can be used as an erection aid, with the bracing member field welded to the gusset plate for the axial load. If a bolted connection is intended to take the axial bracing force, the connection should provide at least 2 bolts.

http://www.FerrellEngineering.com

Providing fabrication and erection efficient structural design of connections. Consulting services for structural welding and bolting.

 

[ghcaste]

connectegr,

Thanks for your input. There is not welding at all, so this is going to be bolted on boths sides. Is this a code requirement? if so, do you know where is it stated on the code?

Thanks again.

 

[connectegr]

In AISC 360-05 D3.3 Effective Net Area
"Members such as single angles, double angles, and WT sections shall have connections proportioned such that U is equal to or greater than 0.60"
This cannot be achieved with a single bolt connection. There are other connection design considerations that also make this an obvious requirement.

Sorry I don't have an electronic copy of CISC Handbook of Steel Construction on my iPad. I don't recall a specific limitation of the shear lag coefficient in S16. If I recall... some mention of two bolts minimum is in the Single-Angles in Compression section (13 I think).

http://www.FerrellEngineering.com

Providing fabrication and erection efficient structural design of connections. Consulting services for structural welding and bolting.

 

[ghcaste]

Thanks a lot connectegr.