W21X55
Wide-Flange Beam · AISC Shapes Database v15.0 · United States
W21X55 is a wide-flange beam 528.3 mm deep with a 208.8 mm flange, weighing 81.9 kg/m. The dimensions below are the published AISC Shapes Database v15.0 values; the drawing is generated from them.
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Published dimensions
| Property | Metric | Imperial |
|---|---|---|
| Depth, d | 528.3 mm | 20.80 in |
| Flange width, bf | 208.8 mm | 8.22 in |
| Flange thickness, tf | 13.3 mm | 0.522 in |
| Web thickness, tw | 9.5 mm | 0.375 in |
| Mass per metre | 81.9 kg/m | 55.0 lb/ft |
| Area, A | 10,452 mm² | 16.20 in² |
| Second moment, Ix | 474,503,826 mm⁴ | 1,140.0 in⁴ |
| Second moment, Iy | 20,145,601 mm⁴ | 48.4 in⁴ |
Derived section properties
Integrated from the section's own outline including the root and toe radii, whose arcs are integrated analytically rather than approximated by facets. For W21X55 the computed area agrees with the published value to 0.01% and Ix to 0.30%. Where a value is also published, the published one above is the one to quote.
| Property | Value |
|---|---|
| Elastic modulus, Zx | 1,801,717 mm³ |
| Elastic modulus, Zy | 193,110 mm³ |
| Plastic modulus, Sx | 2,059,073 mm³ |
| Plastic modulus, Sy | 301,425 mm³ |
| Radius of gyration, rx | 213.4 mm |
| Radius of gyration, ry | 43.9 mm |
Z is the elastic modulus and S the plastic modulus, following AS 4100. Under AISC 360 the letters are reversed — S is elastic and Z is plastic.
Neighbouring sizes
Where these numbers come from
Published AISC Shapes Database v15.0 values. How StructureCalcs verifies its numbers · Understanding steel section properties · Query this section over the API