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1930 steel beam
i am reviewing a building built in 1930 that has some 24" high steel beams. when did the aisc start using the w deesignation? is there a way to determine what beams match up with the existing profiles and what strength designation was in effect?
check out our whitepaper library.
the w designation appeared in the 7th edition aisc manual in 1970.
you can download a spreadsheet from the aisc website that has all of the shapes from then until now. using that tool, you can determine which new beam suitably matches the old one.
my first printing, second edition aisc manual, dated 1/1934, calls for a9 steel for buildings and a7 steel for bridges (both 60 to 72ksi uts). i don't have a first edition at my office, so i can't confirm beyond a shadow of a doubt that this was in effect in 1930.
if you "heard" it on the internet, it's guilty until proven innocent. - dcs
prior to the 7th edition, w shapes were noted as wf (wide flange) or b (light beam). i suggest you obtain a copy of aisc design guide 15. it has
i read that the wide flange beam was introduced around 1928-1930.
"bethlehem structural shapes" catalog s-27, published in 1928 has the following quote on page 3:
quote:
since the inception of the manufacture of bethlehem wide flange structural shapes in 1908, various additions have been made from time to time and improvements adopted in the design and proportions of the series of bethlehem girders and bethlehem i beams.
interestingly, what we would now describe today as a wide flange beam was called a "girder beam" (by bethlehem, in 1928).
the 1928 catalog notes an allowable bending stress of 18 ksi "when loads are quiescent or nearly so" and 12 ksi for moving loads - even lower for impact loads (no number given). allowable web shear is stated as 12 ksi. |
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