HE 900 B vs H-900x300x18x34-286
HE 900 B is an HE section from the European (Continental) range; H-900x300x18x34-286 is the closest equivalent in the European (Continental) range. They are close to interchangeable in bending: 12600 cm³ against 12500 cm³ of plastic modulus, a difference of 0.8%. They weigh essentially the same, 291 kg/m and 286 kg/m. Both are about 906 mm deep, so either fits the same construction zone.
| Property | HE 900 B HE | H-900x300x18x34-286 MB & MC | Difference |
|---|---|---|---|
| Mass | 291 kg/m | 286 kg/m | +1.7% |
| Depth | 900 mm | 912 mm | -1.3% |
| Width | 300 mm | 302 mm | -0.7% |
| Web thickness | 18.5 mm | 18 mm | +2.8% |
| Flange thickness | 35 mm | 34 mm | +2.9% |
| Area | 371 cm² | 364 cm² | +1.9% |
| Second moment, major (Iy) | 494,000 cm⁴ | 497,800 cm⁴ | -0.8% |
| Plastic modulus, major (Wpl,y) | 12,600 cm³ | 12,500 cm³ | +0.8% |
| Elastic modulus, major (Wel,y) | 11,000 cm³ | 10,920 cm³ | +0.7% |
| Second moment, minor (Iz) | 15,800 cm⁴ | 15,670 cm⁴ | +0.8% |
| Plastic modulus, minor (Wpl,z) | 1,660 cm³ | 1,629 cm³ | +1.9% |
| Radius of gyration, minor (iz) | 6.53 cm | 6.56 cm | -0.5% |
| Torsion constant (It) | 1,150 cm⁴ | 1,050 cm⁴ | +9.5% |
HE 900 B to EN 10365 · Continental Steel; H-900x300x18x34-286 to Continental Steel. Difference is expressed relative to H-900x300x18x34-286.
How to choose between them
On stiffness, H-900x300x18x34-286 has the larger second moment of area: 497,800 cm⁴ against 494,000 cm⁴, a difference of 0.8%. 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, the two are equally efficient (43.3 against 43.7 cm³ per kg/m), so on a pure steel-tonnage basis there is nothing to choose between them. The decision comes down to availability, connection detailing and what the rest of the frame uses.
In short, these two are genuine equivalents. Pick whichever your supplier stocks and the rest of the frame already uses.