WB 400 (ISWB 400)

I-beam — 66.71 kg per metre, 85 cm² cross-sectional area. IS 808 Table 1 - Medium & Wide Flange Beams.

zyB 200D 400T 13R2 6.5R1 13t 8.6
Mass per metre
66.71kg/m
Sectional area
85cm²
Depth
400mm
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 16.6; √(I/A) from this row gives 165.92 — the printed figure is the value in cm, in a column headed mm.
  • ryy is printed 4.04; √(I/A) from this row gives 40.29 — the printed figure is the value in cm, in a column headed mm.

WB 400 section properties

As printed in IS 808 Table 1 - Medium & Wide Flange Beams. 400 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 400 mm
Width of flange B 200 mm
Thickness of web t 8.6 mm
Thickness of flange T 13 mm
Flange slope 96 °
Root radius R1 13 mm
Toe radius R2 6.5 mm

Mass and area

Mass per metre M 66.71 kg/m
Sectional area A 85 cm²

Major axis (z-z)

Second moment of area Izz 23,400 cm⁴
Radius of gyration rzz 16.6 mm
Elastic section modulus Zzz 1,170 cm³
Plastic section modulus Zpz 1,320 cm³

Minor axis (y-y)

Second moment of area Iyy 1,380 cm⁴
Radius of gyration ryy 4.04 mm
Elastic section modulus Zyy 138 cm³
Plastic section modulus Zpy 234 cm³

Torsion and warping

Torsion constant (St Venant) It 50.6 cm⁴
Warping constant Iw 6,48,000 cm⁶

What a length of WB 400 weighs

Total weight is the mass per metre multiplied by the length and the number of pieces. Ten pieces of WB 400 at six metres each is 66.71 × 6 × 10 = 4,003 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: 85 cm² of steel at 7 850 kg/m³ is 66.73 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 400

What is the weight of WB 400 per metre?

IS 808 : 2021 gives WB 400 a mass of 66.71 kg per metre. Its printed cross-sectional area of 85 cm² agrees: 85 cm² of steel at 7 850 kg/m³ works out at 66.73 kg per metre.

How much does a 6 m length of WB 400 weigh?

400.26 kg. Mass per metre times length: 66.71 × 6. Ten such pieces come to 4003 kg.

Is WB 400 the same as ISWB 400?

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 400 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 400?

400 mm deep and 200 mm wide, with a 8.6 mm web and 13 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.