NPB 270 × 135

I-beam — 42.26 kg per metre, 53.8 cm² cross-sectional area. IS 808 Table 3 - Narrow Parallel Flange Beams.

zyB 136D 274T 12.2R1 15t 7.5
Mass per metre
42.26kg/m
Sectional area
53.8cm²
Depth
274mm
Width
136mm

Narrow Parallel Flange Beams (NPB). Reproduced as printed in IS 808 Table 3 - Narrow Parallel Flange Beams.

NPB 270 × 135 section properties

As printed in IS 808 Table 3 - Narrow Parallel Flange Beams. 274 mm deep, 136 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 274 mm
Width of flange B 136 mm
Thickness of web t 7.5 mm
Thickness of flange T 12.2 mm
Flange slope 90 °
Root radius R1 15 mm
Toe radius R2 0 mm

Mass and area

Mass per metre M 42.26 kg/m
Sectional area A 53.8 cm²

Major axis (z-z)

Second moment of area Izz 6,940 cm⁴
Radius of gyration rzz 113 mm
Elastic section modulus Zzz 507 cm³
Plastic section modulus Zpz 574 cm³

Minor axis (y-y)

Second moment of area Iyy 513 cm⁴
Radius of gyration ryy 30.8 mm
Elastic section modulus Zyy 75.5 cm³
Plastic section modulus Zpy 117 cm³

Torsion and warping

Torsion constant (St Venant) It 25 cm⁴
Warping constant Iw 87,600 cm⁶

What a length of NPB 270 × 135 weighs

Total weight is the mass per metre multiplied by the length and the number of pieces. Ten pieces of NPB 270 × 135 at six metres each is 42.26 × 6 × 10 = 2,536 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: 53.8 cm² of steel at 7 850 kg/m³ is 42.23 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 NPB 270 × 135

What is the weight of NPB 270 × 135 per metre?

IS 808 : 2021 gives NPB 270 × 135 a mass of 42.26 kg per metre. Its printed cross-sectional area of 53.8 cm² agrees: 53.8 cm² of steel at 7 850 kg/m³ works out at 42.23 kg per metre.

How much does a 6 m length of NPB 270 × 135 weigh?

253.56 kg. Mass per metre times length: 42.26 × 6. Ten such pieces come to 2536 kg.

What are the dimensions of NPB 270 × 135?

274 mm deep and 136 mm wide, with a 7.5 mm web and 12.2 mm flanges.

Free to browse. Log in to unlock the full Rate Analysis of every Civil and Electrical item in the latest CPWD DSR.

Log in to QuickBOQ →

Where these figures come from. IS 808 Table 3 - Narrow Parallel 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.