> I find it strange that most texts including the Salmon & Johnson advise
> that using steel beams composite with concrete slabs generate savings of
> 20% to 30%.
> The design charts and calcs indicate a considerably higher saving
> particularly when beams under 16" are used with slabs 5" and over.This
> is quite common for most buildings under 4 stories high. Deflections
> usually are also fine.
> A typical W10X15 has an permissible Mn of 43 kip ft . When composite
> with a 5" slab the permissible is generally over 75 kip ft. Im I doing
> something wrong
> Mark Francois
This is where LRFD shines, but be warned. Vibration can be a serious
concern with these lighter sections. Refer to AISC publications for a
recommended procedure to check. You might also try Vulcraft composite
joists, if you want a really light section. If you can wait a day or
so, I will try and check the capacity you are mentioning. A couple of
Stud height / diameter / quantity?
Deck orientation / properties?
There are pretty good tables in volume one for rough numbers, have you
Jake Watson, E.I.T.
Salt Lake City, UT