What is the flatness tolerance for webs of built-up girders?
For members in Statically Loaded Structures, web flatness does not affect the structural integrity of a girder because it primarily resists shear. Accordingly, neither the AISC Specification nor the AISC Code of Standard Practice includes a limitation on the out-of-flatness of girder webs. Such a tolerance is specified for welded plate girders, however, in AWS D1.1-2004 Section 5.23.6.2. Shrinkage of web-to-flange welds and/or welds that attach stiffeners to the web can create operational difficulties in girder webs, particular those that are less than 5/16-in. thick. Accordingly, the dimensional tolerance for deviation from flatness of a girder web less than 5/16-in. thick, with or without stiffeners, in Statically Loaded Structures1 should be determined as the larger of 1/2-in. or the value determined in AWS D1.1-2004 Section 5.23.6.2. In Cyclically Loaded Structures2, the value in AWS D1.1-2004 Section 5.23.6.3 should be observed. If architectural considerations require a more restr
