Hat Shape OWSJ Web Yield Strength (Found in Canada)

[EngDM]

Hey all,

I am wondering if anyone has ever come across a reference that shows what the yield strength of the web members typically used in these "Hat Shape" joists as seen in the screenshot below:

The interior web members are typically hollow tubes, so I have been using the DN A53 pipes and going to the nearest size rounding down, and taking 240MPa for my yield. However, every other type of old OWSJ, whether it be Omega or Anthes joists, have been anywhere from 300MPa to 380MPa. I haven't had any success finding a manufacturers table or reference on these joists.

 

[jayrod12]

Those look like GWS chords. They're pretty common and I'd be inclined to say they're closer to 50 ksi (350 MPa).

 

[EngDM]

Those look like GWS chords. They're pretty common and I'd be inclined to say they're closer to 50 ksi (350 MPa).

Just to be clear, you are referring to the webs being 350MPa, I already take the chords as 350MPa.

 

[jayrod12]

I was speaking to the chords.

I just dug out a GWS Industries joist catalogue from 1973. The literature indicates that the chords are 55 ksi (380 MPa) and unfortunately there's no specific indication for the web members.

 

[EngDM]

I just dug out a GWS Industries joist catalogue from 1973.

Do you happen to have an electronic copy of this catalogue?

Much appreciated.

 

[jayrod12]

The other supplier of joists with hat channels that I know of is Dominion Bridge (they were even local to Manitoba). Their catalogue from 1970ish indicates chord yield of 55 ksi and web yield of 50 ksi minimum.

 

[jayrod12]

Sorry, only paper copies. And Not really keen on sitting at the scanner or taking apart the binding to scan it. Hopefully someone can share them from SlideRule's old site.

 

[EngDM]

Dominion Bridge (they were even local to Manitoba)

This project is in Alberta, but we do a lot in Manitoba with these joists. Thank you for informing me of Dominion Bridge, I'll see if I can get a copy.

 

[lexpatrie]

Yeah. I've seen them, but not in Canada. Somebody around here used them in an unsealed crawlspace under a restaurant built on a former swamp.

On an unrelated (yet related) note:
Catastrophic Structural Failure - Roof Collapse at Washingtonville CSD, NYSED.gov web site, August 20, 2004.

That link has pictures, too, but you can't see too much detail.