aisc built-up beam equations

huangyhg

aisc built-up beam equations.
hello,
could you please shed some light on aisc's requirements for the specifying and using steel that has higher yield strength than the minimum given for that grade of steel. for example, how does aisc allow for the use of a500 grade c steel that has a yield stress of 60ksi when the min yield for a500 grade c is 50ksi.
how does the manufacturer justify this yield in their deisgn calculations? are the mill certs from the supplier enough to make the justification? is there any way in the code where this issue is addressed?
thanks for your time.
js.
check out our whitepaper library.
according to aisc seminar "field fixes", mill reports in general can not justify higher steel properties. however, lab report with test of mechanical properties of steel sample is good justification.
good luck.
you also might like to get the aisc steel design guide series 15, "aisc rehabilitation and retrofit guide".  chapter 3 has some excellent information on evaluation of existing structures related to fy from tested pieces.