120x80 RHS — Sizes, Dimensions & Properties

7 sizes in the 120x80 serial size group. All dimensions in mm, section properties in cm units.

Designation	Mass (kg/m)	D (mm)	B (mm)	t (mm)	A (cm2)	Ixx (cm4)	Iyy (cm4)
120x80x3.6	10.8	120	80	3.6	13.7	276	147
120x80x4.0	11.9	120	80	4	15.2	303	161
120x80x5.0	14.7	120	80	5	18.7	365	193
120x80x6.0	17.4	120	80	6	22.2	423	222
120x80x6.3	18.2	120	80	6.3	23.2	440	230
120x80x8.0	22.6	120	80	8	28.8	525	273
120x80x10.0	27.4	120	80	10	34.9	609	313

120x80x3.6 RHS

Designation: 120x80x3.6
Outside Depth (D): 120 mm
Outside Width (B): 80 mm
Wall Thickness (t): 3.6 mm
Mass per Metre: 10.8 kg/m
Cross-Sectional Area: 13.7 cm2
Second Moment of Area Ixx: 276 cm4
Second Moment of Area Iyy: 147 cm4
Elastic Modulus Zxx: 46 cm3
Elastic Modulus Zyy: 36.7 cm3
Plastic Modulus Sxx: 55.6 cm3
Plastic Modulus Syy: 42 cm3
Radius of Gyration rxx: 4.48 cm
Radius of Gyration ryy: 3.27 cm
Torsional Constant (It): 301 cm4
Surface Area per Metre: 0.391 m2/m
Surface Area per Tonne: 36.2 m2/t

120x80x4.0 RHS

Designation: 120x80x4.0
Outside Depth (D): 120 mm
Outside Width (B): 80 mm
Wall Thickness (t): 4 mm
Mass per Metre: 11.9 kg/m
Cross-Sectional Area: 15.2 cm2
Second Moment of Area Ixx: 303 cm4
Second Moment of Area Iyy: 161 cm4
Elastic Modulus Zxx: 50.4 cm3
Elastic Modulus Zyy: 40.2 cm3
Plastic Modulus Sxx: 61.2 cm3
Plastic Modulus Syy: 46.1 cm3
Radius of Gyration rxx: 4.46 cm
Radius of Gyration ryy: 3.25 cm
Torsional Constant (It): 330 cm4
Surface Area per Metre: 0.39 m2/m
Surface Area per Tonne: 32.8 m2/t

120x80x5.0 RHS

Designation: 120x80x5.0
Outside Depth (D): 120 mm
Outside Width (B): 80 mm
Wall Thickness (t): 5 mm
Mass per Metre: 14.7 kg/m
Cross-Sectional Area: 18.7 cm2
Second Moment of Area Ixx: 365 cm4
Second Moment of Area Iyy: 193 cm4
Elastic Modulus Zxx: 60.9 cm3
Elastic Modulus Zyy: 48.2 cm3
Plastic Modulus Sxx: 74.6 cm3
Plastic Modulus Syy: 56.1 cm3
Radius of Gyration rxx: 4.42 cm
Radius of Gyration ryy: 3.21 cm
Torsional Constant (It): 401 cm4
Surface Area per Metre: 0.387 m2/m
Surface Area per Tonne: 26.3 m2/t

120x80x6.0 RHS

Designation: 120x80x6.0
Outside Depth (D): 120 mm
Outside Width (B): 80 mm
Wall Thickness (t): 6 mm
Mass per Metre: 17.4 kg/m
Cross-Sectional Area: 22.2 cm2
Second Moment of Area Ixx: 423 cm4
Second Moment of Area Iyy: 222 cm4
Elastic Modulus Zxx: 70.6 cm3
Elastic Modulus Zyy: 55.6 cm3
Plastic Modulus Sxx: 87.3 cm3
Plastic Modulus Syy: 65.5 cm3
Radius of Gyration rxx: 4.37 cm
Radius of Gyration ryy: 3.17 cm
Torsional Constant (It): 468 cm4
Surface Area per Metre: 0.385 m2/m
Surface Area per Tonne: 22.1 m2/t

120x80x6.3 RHS

Designation: 120x80x6.3
Outside Depth (D): 120 mm
Outside Width (B): 80 mm
Wall Thickness (t): 6.3 mm
Mass per Metre: 18.2 kg/m
Cross-Sectional Area: 23.2 cm2
Second Moment of Area Ixx: 440 cm4
Second Moment of Area Iyy: 230 cm4
Elastic Modulus Zxx: 73.3 cm3
Elastic Modulus Zyy: 57.6 cm3
Plastic Modulus Sxx: 91 cm3
Plastic Modulus Syy: 68.2 cm3
Radius of Gyration rxx: 4.36 cm
Radius of Gyration ryy: 3.15 cm
Torsional Constant (It): 487 cm4
Surface Area per Metre: 0.384 m2/m
Surface Area per Tonne: 21.1 m2/t

120x80x8.0 RHS

Designation: 120x80x8.0
Outside Depth (D): 120 mm
Outside Width (B): 80 mm
Wall Thickness (t): 8 mm
Mass per Metre: 22.6 kg/m
Cross-Sectional Area: 28.8 cm2
Second Moment of Area Ixx: 525 cm4
Second Moment of Area Iyy: 273 cm4
Elastic Modulus Zxx: 87.5 cm3
Elastic Modulus Zyy: 68.1 cm3
Plastic Modulus Sxx: 111 cm3
Plastic Modulus Syy: 82.6 cm3
Radius of Gyration rxx: 4.27 cm
Radius of Gyration ryy: 3.08 cm
Torsional Constant (It): 587 cm4
Surface Area per Metre: 0.379 m2/m
Surface Area per Tonne: 16.8 m2/t

120x80x10.0 RHS

Designation: 120x80x10.0
Outside Depth (D): 120 mm
Outside Width (B): 80 mm
Wall Thickness (t): 10 mm
Mass per Metre: 27.4 kg/m
Cross-Sectional Area: 34.9 cm2
Second Moment of Area Ixx: 609 cm4
Second Moment of Area Iyy: 313 cm4
Elastic Modulus Zxx: 102 cm3
Elastic Modulus Zyy: 78.1 cm3
Plastic Modulus Sxx: 131 cm3
Plastic Modulus Syy: 97.3 cm3
Radius of Gyration rxx: 4.18 cm
Radius of Gyration ryy: 2.99 cm
Torsional Constant (It): 688 cm4
Surface Area per Metre: 0.374 m2/m
Surface Area per Tonne: 13.7 m2/t

120x80 RHS — Overview

The 120x80 serial size group contains 7 sections, ranging from 27.4 kg/m to 10.8 kg/m. All sections in this group share the same nominal depth and width but differ in web and flange thickness, which affects the weight and structural capacity.

Section properties are sourced from the Tata Steel Blue Book / SCI P363. For structural design to BS EN 1993-1-1 (Eurocode 3), use these properties with the appropriate partial factors from the UK National Annex.

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Section properties from Tata Steel Blue Book / SCI P363 / BS 4-1:2005.