StructureCalcsS12X40.8
American Standard Beam · AISC Shapes Database v15.0 · United States
S12X40.8 is an American Standard beam 304.8 mm deep with a 133.4 mm wide flange, weighing 60.7 kg/m. The dimensions below are the published AISC Shapes Database v15.0 values; the drawing is generated from them.
S-shapes are American Standard beams with narrow, tapered flanges — the oldest rolled I-profile in the catalogue, still used for crane rails and work on older structures.
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Published dimensions
| Property | Metric | Imperial |
|---|---|---|
| Depth, d | 304.8 mm | 12.00 in |
| Flange width, bf | 133.4 mm | 5.25 in |
| Flange thickness, tf | 16.7 mm | 0.659 in |
| Web thickness, tw | 11.7 mm | 0.462 in |
| Mass per metre | 60.7 kg/m | 40.8 lb/ft |
| Area, A | 7,677 mm² | 11.90 in² |
| Second moment, Ix | 112,382,485 mm⁴ | 270.0 in⁴ |
| Second moment, Iy | 5,619,124 mm⁴ | 13.5 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 S12X40.8 the computed area agrees with the published value to better than 0.01% and Ix to 0.07%. Where a value is also published, the published one above is the one to quote.
| Property | Value |
|---|---|
| Elastic modulus, Sx | 737,945 mm³ |
| Elastic modulus, Sy | 86,204 mm³ |
| Plastic modulus, Zx | 861,738 mm³ |
| Plastic modulus, Zy | 145,892 mm³ |
| Radius of gyration, rx | 121.0 mm |
| Radius of gyration, ry | 27.4 mm |
S is the elastic modulus and Z the plastic modulus, following AISC 360. Australian and British practice reverse the letters.
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