Simply Supported Beam Design
Simply Supported Beam Design
(OP)
I am reviewing a design that has a beam subjected to 200k-ft max moment and a 32 ft span, the designer has specified a W21x44. When I checked the beam via ASD the compressive flange would have to be braced at least every 4.7-ft to meet the flange criteria. I think the designer is just selecting the beam by Mr method without checking the unbraced length. Am I interpreting this correctly?






RE: Simply Supported Beam Design
RE: Simply Supported Beam Design
RE: Simply Supported Beam Design
Page 2-168: W21 X 44 (A36 Steel) is good for maxiumum moment of about 163 kip-ft, no matter how short the unbraced length. The limiting factor is the allowable shear strength of the web.
However - For steel with Fy = 50 ksi, the W21 x 44 is the lightest section for the 200 kip-ft moment (page 2-202). The unbraced length would have to < or = about 6.2 ft (the intersection of the line for the W21 x 44 and 200 kip-ft moment).
RE: Simply Supported Beam Design
RE: Simply Supported Beam Design
RE: Simply Supported Beam Design