Section Family
RHS Section Properties Calculator
Use a rectangular hollow section preset to compare wall thickness, major-axis inertia, and section efficiency before running a beam or column check.
Geometric Inputs
Section Shape
Section Blueprint
Cross-sectional Area3456.0 mm²
Weight per meter27.13 kg/m
Technical Properties
Inertia (Ix)599.0 cm⁴
Inertia (Iy)1793.9 cm⁴
Modulus (Wx)119.8 cm³
Modulus (Wy)179.4 cm³
Radius (ix)41.6 mm
Radius (iy)72.0 mm
Calculation Basis
Assumptions & Limits
- Geometry is idealized without fillet radii, rolling tolerances, or local cut-outs.
- Weight per meter is based on standard steel density and should be treated as an engineering estimate.
- For real section tables, manufacturer or code values should still be checked against the entered dimensions.
Reference Basis
- Documentation: Methodology
- Documentation: Engineering Review
- Roark's Formulas for Stress and Strain
- Mechanics of Materials references
- Classical section-property references
Starter RHS Dimensions
| Depth H | 100 mm |
| Width B | 200 mm |
| Wall thickness t | 6 mm |
| Section type | Closed rectangular hollow section |
| Best use | Bending and torsion-conscious preliminary sizing |
How To Use This Page
- RHS sections are efficient when you need clean torsional behavior and compact depth, but the wall thickness has a strong effect on weight and stiffness together.
- Compare Ix and Iy deliberately, because RHS members are often rotated depending on architectural depth limits or secondary framing direction.
- Once the section is selected, continue into the beam solver for vertical response or into a slenderness-focused page when column action matters more.
Key Formulas
- Area: A = B H - (B - 2 t)(H - 2 t). Gross hollow-section area without corner-radius correction.
- Major-axis inertia: Ix = [B H^3 - (B - 2 t)(H - 2 t)^3] / 12. Useful when the deeper side is vertical.
- Minor-axis inertia: Iy = [H B^3 - (H - 2 t)(B - 2 t)^3] / 12. Important whenever the member could be rotated or loaded biaxially.
Frequently Asked Questions
- Does this page include corner radii from manufacturer tables? No. The page uses the standard idealized hollow-section formulas, so it is best for early-stage engineering comparison rather than final catalog certification.
- Why are both Ix and Iy important on RHS pages? Because rectangular hollow sections are often rotated in practice. A member that is stiff in one orientation can become much softer if the depth and width swap places.
- Should I use this page for beam checks or column checks? Use it for both as a starting point. The page gives the section properties first, then you can move into beam deflection or column-slenderness review depending on the governing action.
Related Pages