location of minmax camber
 

location of min/max camber
i have to apologize for this question, but where do you find the minimum and maximum cambers for steel shapes? i have been looking through the 13th edition steel manual, but can't find it. i found it once before, but didn't tab it.
eit, i dont know where it is on the manual but i have an intersting article from modern steel construction july 2006 by erika winters downey. she wrote a list when not to camber a
i have that article, too. it is good, but i have some long beams (around 70') that would only need to be cambered around 1" to 1.25" and i think that may be less than the minimum for a 70' w36
see table 1-10 (p1-186) of the second edition lrfd manual (silver one). table was subsequently removed from 3rd. ed. manual - did not think it was placed in the 13th but i could be mistaken.
fwiw:
looking back over several office building jobs over the last several years, i have often shown 1" to 1.5" camber for 60' to 70' w30's. the local fabricators don't seem to have a problem with this, as i have never had a question on it.
if you need a camber for a 70' beam then i would be very careful about the vibration.
i've already checked vibrations. i am under l/240 for total deflection, but on a 70' span that's still pretty high, so i'm just trying to cut down on the magnitude of deflection.
have you tried using composite joists or is depth a limitation?
i am not sure if this is exactly what you're looking for but you can check out section 16.3-27 in the code of standard practice aisc thirteenth edition (6.4 fabrication tolerances).
jb
astm a6 gives a lot of information about the quality requirements for steel plate and rolled shapes, including permissable camber. you may be able to learn something from that spec. good luck.