W 12X96 vs HE 340 B
W 12X96 is an W section from the American AISC Shapes Database; HE 340 B is the closest equivalent in the European (Continental) range. They are close to interchangeable in bending: 2408.9 cm³ against 2410 cm³ of plastic modulus, a difference of 0.0%. HE 340 B is the lighter of the two at 134 kg/m against 142.9 kg/m, a saving of 6.6% on steel weight. HE 340 B is deeper, 340 mm against 322.6 mm, which matters where the floor zone is tight.
| Property | W 12X96 W | HE 340 B HE | Difference |
|---|---|---|---|
| Mass | 142.9 kg/m | 134 kg/m | +6.6% |
| Depth | 322.6 mm | 340 mm | -5.1% |
| Width | 309.9 mm | 300 mm | +3.3% |
| Web thickness | 14 mm | 12 mm | +16.7% |
| Flange thickness | 22.9 mm | 21.5 mm | +6.5% |
| Area | 181.9 cm² | 171 cm² | +6.4% |
| Second moment, major (Iy) | 34,672 cm⁴ | 36,700 cm⁴ | -5.5% |
| Plastic modulus, major (Wpl,y) | 2,408.9 cm³ | 2,410 cm³ | same |
| Elastic modulus, major (Wel,y) | 2,146.7 cm³ | 2,160 cm³ | -0.6% |
| Second moment, minor (Iz) | 11,238 cm⁴ | 9,690 cm⁴ | +16.0% |
| Plastic modulus, minor (Wpl,z) | 1,106.1 cm³ | 986 cm³ | +12.2% |
| Radius of gyration, minor (iz) | 7.85 cm | 7.53 cm | +4.2% |
| Torsion constant (It) | 285.1 cm⁴ | 263 cm⁴ | +8.4% |
W 12X96 to AISC Shapes Database v16.0; HE 340 B to EN 10365 · Continental Steel. Difference is expressed relative to HE 340 B.
How to choose between them
On stiffness, HE 340 B has the larger second moment of area: 36,700 cm⁴ against 34,672 cm⁴, a difference of 5.5%. This matters more often than the strength comparison, because on normal floor spans deflection rather than bending capacity sets the beam size - so if the two are close on modulus but apart on inertia, the stiffer one is usually the better answer even when it is not the stronger one.
Measured as bending capacity per kilogram of steel, HE 340 B is the more efficient section: 18.0 against 16.9 cm³ per kg/m, 6.3% better. Over a floor of repeated beams that difference is real tonnage, though it is often outweighed by whichever section the fabricator can actually source.
The two diverge much more about the minor axis: W 12X96 has 1106.1 cm³ of minor-axis plastic modulus against 986 cm³, 12.2% more. If the member sees any minor-axis bending, or if it is unrestrained over a long length and lateral-torsional buckling governs, that gap decides the comparison even though the major-axis numbers looked equivalent.
These come from different catalogues, so treat the swap as a design change rather than a like-for-like substitution. W sections are specified to AISC Shapes Database v16.0 and HE to EN 10365 · Continental Steel; the steel grades, tolerances and available lengths differ, connection details and bolt gauges are set out differently, and the two are rarely both stocked in the same market. Check availability before changing a section on a drawing to save 6.6% weight.
In short, HE 340 B is the stronger section and HE 340 B is the lighter one; where those are the same section, it is the clear choice, and where they are not, decide on whether your design is governed by capacity or by tonnage.