T-shape chords of steel joist

[Deadblow]

Hello All,

I have some existing plans for a project built in 1957. The plans call for "SJ 146" steel joists to support the flat roof. I easily found the load tables associated with this steel joist designation in the 75-Year Steel Joist Manual, so I thought my job of analyzing the joists was going to be simple. Then I was given the attached picture of the joists and informed that the top and bottom chords are "T"-shaped not double angles. Could these steel joists actually be the "SJ 146" called for on the plans, or are these joists different? The depth of the joists are indeed 14 inches like the call out on the plans indicates. I have never seen joists with "T" chord members before. Are there any references that include this type of joist?

If they are the "SJ 146", I'm coming up with about a 67 psf capacity for the 26'-0" span. This capacity seems plausible. I was hoping for a design capacity of at least 45 psf.

Thanks for any input!

EIT

 

[Hokie93]

A co-worker has been dealing with the same type of joist on a renovation project. In his project (originally designed in 1956), the joists were 8 inches and 10 inches deep but, in both cases, they had that exact 'tee' chord. We pulled the capacity from the 60-year SJI Joist Manual. So, yes, I believe that is the "SJI 146" called out on the original construction drawings.

 

[BUGGAR]

My old memory says check the SJI "Rules" of the time: Steel joists were built to performance specifications and mostly had to meet only strength, deflection, and depth requirements. Any chord members were fair game as long as the assembly passed those requirements.
In the old days, T's used to detail well for truss chords.
(ps: don't try to uphold AWS weld specs on SJI steel joists in Court.)

 

[Deadblow]

Hokie and Buggar,

Thank you both for the valuable input! I'll plan to take field measurements and analyze the capacity and compare that to the load tables.

EIT