400x300 RHS — Sizes, Dimensions & Properties

5 sizes in the 400x300 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)
400x300x8.0	85.4	400	300	8	109	25,700	16,500
400x300x10.0	106	400	300	10	135	31,500	20,200
400x300x12.5	131	400	300	12.5	167	38,500	24,600
400x300x14.2	148	400	300	14.2	189	43,000	27,400
400x300x16.0	166	400	300	16	211	47,500	30,300

400x300x8.0 RHS

Designation: 400x300x8.0
Outside Depth (D): 400 mm
Outside Width (B): 300 mm
Wall Thickness (t): 8 mm
Mass per Metre: 85.4 kg/m
Cross-Sectional Area: 109 cm2
Second Moment of Area Ixx: 25,700 cm4
Second Moment of Area Iyy: 16,500 cm4
Elastic Modulus Zxx: 1,290 cm3
Elastic Modulus Zyy: 1,100 cm3
Plastic Modulus Sxx: 1,520 cm3
Plastic Modulus Syy: 1,250 cm3
Radius of Gyration rxx: 15.4 cm
Radius of Gyration ryy: 12.3 cm
Torsional Constant (It): 31,000 cm4
Surface Area per Metre: 1.38 m2/m
Surface Area per Tonne: 16.2 m2/t

400x300x10.0 RHS

Designation: 400x300x10.0
Outside Depth (D): 400 mm
Outside Width (B): 300 mm
Wall Thickness (t): 10 mm
Mass per Metre: 106 kg/m
Cross-Sectional Area: 135 cm2
Second Moment of Area Ixx: 31,500 cm4
Second Moment of Area Iyy: 20,200 cm4
Elastic Modulus Zxx: 1,580 cm3
Elastic Modulus Zyy: 1,350 cm3
Plastic Modulus Sxx: 1,870 cm3
Plastic Modulus Syy: 1,540 cm3
Radius of Gyration rxx: 15.3 cm
Radius of Gyration ryy: 12.2 cm
Torsional Constant (It): 38,200 cm4
Surface Area per Metre: 1.37 m2/m
Surface Area per Tonne: 12.9 m2/t

400x300x12.5 RHS

Designation: 400x300x12.5
Outside Depth (D): 400 mm
Outside Width (B): 300 mm
Wall Thickness (t): 12.5 mm
Mass per Metre: 131 kg/m
Cross-Sectional Area: 167 cm2
Second Moment of Area Ixx: 38,500 cm4
Second Moment of Area Iyy: 24,600 cm4
Elastic Modulus Zxx: 1,920 cm3
Elastic Modulus Zyy: 1,640 cm3
Plastic Modulus Sxx: 2,300 cm3
Plastic Modulus Syy: 1,880 cm3
Radius of Gyration rxx: 15.2 cm
Radius of Gyration ryy: 12.1 cm
Torsional Constant (It): 46,800 cm4
Surface Area per Metre: 1.37 m2/m
Surface Area per Tonne: 10.5 m2/t

400x300x14.2 RHS

Designation: 400x300x14.2
Outside Depth (D): 400 mm
Outside Width (B): 300 mm
Wall Thickness (t): 14.2 mm
Mass per Metre: 148 kg/m
Cross-Sectional Area: 189 cm2
Second Moment of Area Ixx: 43,000 cm4
Second Moment of Area Iyy: 27,400 cm4
Elastic Modulus Zxx: 2,150 cm3
Elastic Modulus Zyy: 1,830 cm3
Plastic Modulus Sxx: 2,580 cm3
Plastic Modulus Syy: 2,110 cm3
Radius of Gyration rxx: 15.1 cm
Radius of Gyration ryy: 12.1 cm
Torsional Constant (It): 52,500 cm4
Surface Area per Metre: 1.36 m2/m
Surface Area per Tonne: 9.2 m2/t

400x300x16.0 RHS

Designation: 400x300x16.0
Outside Depth (D): 400 mm
Outside Width (B): 300 mm
Wall Thickness (t): 16 mm
Mass per Metre: 166 kg/m
Cross-Sectional Area: 211 cm2
Second Moment of Area Ixx: 47,500 cm4
Second Moment of Area Iyy: 30,300 cm4
Elastic Modulus Zxx: 2,380 cm3
Elastic Modulus Zyy: 2,020 cm3
Plastic Modulus Sxx: 2,870 cm3
Plastic Modulus Syy: 2,350 cm3
Radius of Gyration rxx: 15 cm
Radius of Gyration ryy: 12 cm
Torsional Constant (It): 58,300 cm4
Surface Area per Metre: 1.36 m2/m
Surface Area per Tonne: 8.2 m2/t

400x300 RHS — Overview

The 400x300 serial size group contains 5 sections, ranging from 166 kg/m to 85.4 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.