I just noticed:
> 20DH9 (below)
should be 26DH9.
> These appear to be Armco Deep High Strength Shortspan joists.
> 20DH8 Capacity 280#/ft based on strength (38' span)
> Capacity 145#/ft based on deflection L/360
> 20DH9 Capacity 372#/ft based on strength (36' span)
> Capacity 197#/ft based on deflection L/360
> I can fax you the pages from Armco's booklet if you would like.
> A. Roger Turk, P.E.(Structural)
> Tucson, Arizona
> Ed Fasula wrote:
> >>I'm looking at a '72 built school for re-roof, they intend
> to remove the
> existing built-up roofing system and replace it with a new ballasted
> membrane roofing system.
> In order to check the capacity of the steel joists, I looked into the
> 50-Year Steel Joist Digest by the SJI. Unfortunately, the
> joists shown on
> the original building plans are not listed. First of all,
> can anything be
> learned from these non-standard spec numbers - second if so,
> what or how??
> Obviously, the alternative is to analyze the joists, but the
> ceiling finish
> would have to go.
> Here are the numbers listed (they are shown clearly on the plans):
> 20DH8 (6'-6" o.c. & span 37'-8")
> 26DH9 (6'-6" o.c. & span 35'-8")