WB 250 (ISWB 250)

I-beam — 40.84 kg per metre, 52 cm² cross-sectional area. IS 808 Table 1 - Medium & Wide Flange Beams.

zyB 200D 250T 9R2 5R1 10t 6.7
Mass per metre
40.84kg/m
Sectional area
52cm²
Depth
250mm
Width
200mm

Medium & Wide Flange Beams (MB, WB). Reproduced as printed in IS 808 Table 1 - Medium & Wide Flange Beams.

A radius of gyration here disagrees with this row’s own I and A

  • rzz is printed 10.6; √(I/A) from this row gives 106.88 — the printed figure is the value in cm, in a column headed mm.
  • ryy is printed 4.05; √(I/A) from this row gives 40.6 — the printed figure is the value in cm, in a column headed mm.

WB 250 section properties

As printed in IS 808 Table 1 - Medium & Wide Flange Beams. 250 mm deep, 200 mm wide. Units are shown on every row, because the two standards on this site use different ones for the radius of gyration.

Dimensions

Depth of section D 250 mm
Width of flange B 200 mm
Thickness of web t 6.7 mm
Thickness of flange T 9 mm
Flange slope 96 °
Root radius R1 10 mm
Toe radius R2 5 mm

Mass and area

Mass per metre M 40.84 kg/m
Sectional area A 52 cm²

Major axis (z-z)

Second moment of area Izz 5,940 cm⁴
Radius of gyration rzz 10.6 mm
Elastic section modulus Zzz 475 cm³
Plastic section modulus Zpz 527 cm³

Minor axis (y-y)

Second moment of area Iyy 857 cm⁴
Radius of gyration ryy 4.05 mm
Elastic section modulus Zyy 85.7 cm³
Plastic section modulus Zpy 149 cm³

Torsion and warping

Torsion constant (St Venant) It 17.8 cm⁴
Warping constant Iw 1,74,000 cm⁶

What a length of WB 250 weighs

Total weight is the mass per metre multiplied by the length and the number of pieces. Ten pieces of WB 250 at six metres each is 40.84 × 6 × 10 = 2,450 kg. There is nothing else to it — the standard publishes the mass, so no one needs to compute it from the area.

You can check that mass against the area on this page: 52 cm² of steel at 7 850 kg/m³ is 40.82 kg/m. Every row in this dataset was checked that way, which is how the contradictions flagged on some of these pages were found.

Work it out for your own lengths and quantities →

Common questions about WB 250

What is the weight of WB 250 per metre?

IS 808 : 2021 gives WB 250 a mass of 40.84 kg per metre. Its printed cross-sectional area of 52 cm² agrees: 52 cm² of steel at 7 850 kg/m³ works out at 40.82 kg per metre.

How much does a 6 m length of WB 250 weigh?

245.04 kg. Mass per metre times length: 40.84 × 6. Ten such pieces come to 2450 kg.

Is WB 250 the same as ISWB 250?

It is the same section under the name IS 808 : 2021 gives it — the 2021 revision of IS 808 dropped the "IS" prefix, so a drawing saying ISWB 250 means this section. Check the edition before assuming the figures match, though: this page publishes the current tables, and a great many tables in circulation were copied from the 1989 edition.

What are the dimensions of WB 250?

250 mm deep and 200 mm wide, with a 6.7 mm web and 9 mm flanges.

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Where these figures come from. IS 808 Table 1 - Medium & Wide Flange Beams Section properties are facts published in the standards, and they are reproduced here as printed. Where a standard contradicts itself, both of its figures are shown and neither is corrected.

What is ours. The selection and arrangement of these tables, the checks run against them, and the findings those checks produced — which rows disagree with themselves, which figures were superseded by amendment, and which could not be read — are QuickBOQ’s work, and so is this wording. Quote the numbers freely; they belong to everyone. Copying the compilation and the commentary is a different thing, and we would rather you linked to it.