Search

Steel Interchange


Historic Beam Designation
I am investigating a building designed in 1967, with the plans dated February 1, 1968. The plans indicate some roof beams as being 18B35. I have a 6th edition AISC Manual dated 1967 and this shape is not indicated. Can you tell me where I might find the properties of this shape?

Answer

There was a grouping of light 18-in. beams (W18×40 and W18×35) that were added in the 7th edition AISC Manual published in 1970. I believe that these shapes were added by some mills in the late 1960s. It is possible that this may be what is designated as an 18B35, even though it was designated as a W18×35 by the time the Manual was published. You may want to check the dimensions of the shape against those listed in the 7th edition AISC Manual to see if that is what you have.


In case you do not have a copy of the 7th edition Manual, AISC has developed two sources of information pertaining to historic shapes. AISC Steel Design Guide 15 is a reference for historic shapes and specifications. There is also the AISC Shapes Database v13.1H, where the H stands for Historic. Both of these resources are available as free downloads by AISC members at www.aisc.org/epubs or can be purchased by others.

 

Kurt Gustafson, S.E., P.E.

Posted on July 1, 2010


Please feel free to submit a question/answer to solutions@aisc.org