W18×71 wide-flange beam

Detailing dimensions and section properties from the AISC Shapes Database, 16th Edition. Values are shown to the nearest 1/16 in. as they appear on a shop drawing.

W18×71 measures 18 1/2 in. deep with a 7 5/8 in. flange, on a 1/2 in. web and 13/16 in. flanges.

At 71 lb per foot it is one of the 23 W18 sizes, which run from 35 to 311 lb/ft.

For strong-axis bending its section modulus is Sx = 127 in³ and its moment of inertia Ix = 1170 in⁴, with a plastic modulus Zx = 146 in³.

Detailing dimensions

Depth (d)18 1/2"
Flange width (bf)7 5/8"
Web thickness (tw)1/2"
Flange thickness (tf)13/16"
k (detailing)1 1/2"
Workable gage (g)3 1/2"

Section properties

Weight71 lb/ft
Area (A)20.9 in²
Ix1170 in⁴
Sx127 in³
Zx146 in³
rx7.5 in
Iy60.3 in⁴
Sy15.8 in³
Zy24.7 in³
ry1.7 in
J3.49 in⁴

Other W18 sizes

Same nominal size, different weight — useful when you are checking a substitution or a lighter section.

W18×35W18×40W18×46W18×50W18×55W18×60W18×65W18×76W18×86W18×97W18×106W18×119W18×130W18×143W18×158W18×175W18×192W18×211W18×234W18×258W18×283W18×311

All W18 sizes and dimensions →

Similar weight wide-flange beams

Comparable 71 lb/ft sections in other wide-flange beam sizes.

W12×7272 lb/ft · Sx 97.4 in³W21×7373 lb/ft · Sx 151 in³W24×6868 lb/ft · Sx 154 in³W21×6868 lb/ft · Sx 140 in³W14×6868 lb/ft · Sx 103 in³W10×6868 lb/ft · Sx 75.7 in³W14×7474 lb/ft · Sx 112 in³W16×6767 lb/ft · Sx 117 in³

Compare W18×71 with a nearby size

W18×65 vs W18×71W18×71 vs W18×76

Detailing values are rounded to the nearest 1/16 in. per the AISC Steel Construction Manual. Verify critical dimensions against the current Manual before fabrication. Need W18×71 cut, formed, or fabricated? Huntington Steel & Supply Co.

Browse more: Wide flange beams · Steel Beam Size Chart

Interactive drawing