Column Buckling Calculator

Enter a symmetric I/H (W-shape) section's dimensions, its steel grade, the effective lengths about each axis, and the factored axial load, to check the factored compressive resistance in flexural buckling to CSA S16.

Standards used on this page:CSA S16-19 Clause 13.3.1 (factored compressive resistance, flexural buckling) · Cr = φ A Fy (1 + λ2n)-1/n, with φ = 0.90 and n = 1.34 (hot-rolled / welded W-shapes) · Limit States Design throughout.
Scope of this tool: flexural buckling of Class 1-3 (non-slender) sections only. Class 4 (slender) sections are flagged and excluded. Torsional and flexural-torsional buckling (Clause 13.3.2) and torsion (Clause 13.7) are not checked, nor is combined axial + bending (Clause 13.8) - this is a pure axial-compression tool.
Note on accuracy: this tool assumes sharp (unfilleted) corners, so computed section properties (and hence Cr) run about 1-2% below the CISC published (filleted) values - adequate for preliminary sizing. Enter the effective length KL (i.e. K × L already applied) for each axis.
Section
Effective lengths and load
kN
This calculator provides preliminary, indicative structural calculations only, intended to assist with initial sizing and understanding. It is not a substitute for assessment by a qualified structural engineer, and ca.cad-steel.com accepts no responsibility for its use in any final design.