steel beams from 1906
steel beams from 1906
(OP)
i am checking some steel beams from 1906 in New York City. Based on AISC at that time, the allowable bending stress was around 16 to 18 ksi. However i have tested the material and found that the yield stress is 38300psi and the tensile strength is 64300psi. The percent elongation in 2" is 26.5%. According to today's AISC code the allowable bending stress is around 24ksi. Csn you think of any reason why not to use the higher allowable stress?
thanks
thanks





RE: steel beams from 1906
Have you checked to see if there is any wrought iron mixed in among the steel, brackets and braces.
Just for curosity who made the Steel for the beams?
RE: steel beams from 1906
carbon 0.2
manganese 0.97
phosphorus 0.044
sulphur 0.03
silicon < .01
chromium <.01
nickel 0.03
RE: steel beams from 1906
I would be worried about overall consistancy of the beams end to end and beam to beam however.
nick
RE: steel beams from 1906
RE: steel beams from 1906
RE: steel beams from 1906
RE: steel beams from 1906
RE: steel beams from 1906
Again based on my recollection of these events in my younger days I wouldn’t push the envelope even though the design of times probably would have been quite conservitive by today’s standards, simply by the methods of calculations used.
P.S.
The tensile testing machines of the time weren't very good as a lot depended on the operator keeping the beam balanced. There was a propensity to throw out very bad values if the fracture surface had discernible imperfections.