Indian Standard Medium Weight Beam per IS 808 : 1989 — depth 300mm, flange width 140mm, web thickness 7.7mm, flange thickness 13.1mm, weight 44.2 kg/m.
| Property | About X-X Axis | About Y-Y Axis |
|---|---|---|
| Moment of Inertia (I) | 86,030,000 mm⁴ (8603.0 cm⁴) | 4,530,000 mm⁴ (453.0 cm⁴) |
| Elastic Section Modulus (Z) | 573,600 mm³ (573.6 cm³) | 64,700 mm³ (64.7 cm³) |
| Plastic Section Modulus (Zp) | 664,100 mm³ (664.1 cm³) | 102,300 mm³ (102.3 cm³) |
| Radius of Gyration (r) | 123.6 mm | 28.4 mm |
| Distance to Extreme Fibre (c) | 150.0 mm (d/2) | 70.0 mm (b/2) |
| Shape Factor (Zp/Z) | 1.158 | 1.581 |
| Torsional Constant (It) | 236,000 mm⁴ (23.6 cm⁴) | |
| Warping Constant (Iw) | 140,000,000,000 mm⁶ | |
| Polar Moment (Ip = Ix + Iy) | 90,560,000 mm⁴ (9056.0 cm⁴) | |
Useful for paint estimation, fire protection coating quantities, and section analysis:
Surface area calculated from full cross-section perimeter including flange tips. Shear area Av = d × tw per IS 800 : 2007 cl. 8.4. Surface/mass ratio used for estimating paint and fireproofing coverage per kg of steel.
Calculated per IS 800 : 2007 (limit state design) using partial safety factor γm0 = 1.10. Values assume the section is fully laterally restrained. Reduce for unsupported lengths per IS 800 cl. 8.2.
| Grade | Plastic Moment Mp (X-X) | Plastic Moment Mp (Y-Y) | Axial Capacity (Short) |
|---|---|---|---|
| E 250 | 150.9 kN·m | 23.2 kN·m | 1280 kN |
| E 350 | 211.3 kN·m | 32.5 kN·m | 1791 kN |
| E 410 | 247.5 kN·m | 38.1 kN·m | 2098 kN |
| E 450 | 271.7 kN·m | 41.9 kN·m | 2303 kN |
Mp = Zp × fy / γm0. Axial capacity = A × fy / γm0 for short, fully-restrained columns. For longer columns, apply slenderness reduction per IS 800 cl. 7.1.2.
| Standard | Equivalent Section | Depth | Weight |
|---|---|---|---|
| India (IS 808) | ISMB 300 | 300 mm | 44.2 kg/m |
| Europe (EN) | IPE 300 | — | — |
| UK (BS) | 305×127×37 UB | — | — |
| USA (ASTM) | W12×30 | — | — |
| Japan (JIS) | H 300×150 | — | — |
| Germany (DIN) | I 300 | — | — |
Equivalence based on closest matching depth and weight. Note that ISMB has tapered flanges (8° slope per IS 808) while IPE, UB, and W-shapes have parallel flanges. Always verify exact properties from the actual standard before substituting in design calculations.
| Grade | Yield (MPa) | UTS (MPa) | Elong. | Application |
|---|---|---|---|---|
| E250 (Fe 410W) | 250 | 410 | 23% | General construction |
| E275 (Fe 440) | 275 | 440 | 22% | Commercial buildings |
| E300 | 300 | 440 | 22% | Industrial structures |
| E350 (Fe 490) | 350 | 490 | 22% | Heavy industrial, bridges |
| E410 (Fe 540) | 410 | 540 | 20% | Heavy structural, offshore |
| E450 (Fe 570) | 450 | 570 | 20% | Bridges, towers |