----------: | :-------------: | :-----------------------: | | 200-400 | IPE 200-240 | 350-750 kN | | 400-800 | HEA 180-240 | 900-1800 kN | | 800-1500 | HEB 200-280 | 2000-3500 kN | | 1500-3000 | HEB 300-400 | 4000-8000 kN | | 3000+ | HEM or built-up | 8000+ kN |

Related Resources

• European Column Buckling Guide
• European Steel Grades — fy and fu Values
• European Column K-Factor Guide
• European Beam Design Guide
• EN 1993 Combined Loading Guide
• EN 1993 Lateral-Torsional Buckling
• EN 1993 Base Plate Design
• Beam Capacity Calculator — EN 1993

FAQ

What buckling curves does the calculator use? EN 1993-1-1 provides five buckling curves (a0, a, b, c, d). The calculator selects the appropriate curve based on the section type, axis (major/minor), flange thickness, and steel grade per Table 6.2. HEA/HEB sections with tf ≤ 40 mm use curve b for major axis and curve c for minor axis. IPE sections use curve a for major axis and curve b for minor axis (tf ≤ 40 mm).

How is the non-dimensional slenderness calculated? lambda_bar = (L_cr / i) / (pi x sqrt(E / fy)) where L_cr is the buckling length, i is the radius of gyration, and lambda_1 = 93.9 epsilon with epsilon = sqrt(235/fy). For S355 steel, lambda_1 = 93.9 x sqrt(235/355) = 76.4. The non-dimensional slenderness normalises all sections and steel grades to the same basis.

Does the calculator check combined axial compression and bending? Yes. The interaction formula per Clause 6.3.3 accounts for both major and minor axis bending with the appropriate interaction factors k_yy, k_yz, k_zy, and k_zz from Annex B. For biaxial bending, both in-plane and out-of-plane checks are performed.

How does the column design differ between braced and sway frames? In braced frames (Clause 5.2.1), columns carry predominantly axial load with minimal end moments from eccentricity. K is typically ≤ 1.0. In sway frames (Clause 5.2.2), columns resist significant bending moments from lateral drift in addition to axial load, and K > 1.0 must be determined by frame stability analysis. Sway frames always require the combined compression + bending check.

What are the standard European column sections? HEA sections (wide flange, light/medium weight) are the most common European column sections. HEB sections (wider flange, heavier weight) are used where higher capacity is needed. For very heavy columns, HEM sections (extra-wide flange) are available. IPE sections are primarily beam sections but used as light columns. European hollow sections (RHS, CHS per EN 10210/10219) are also widely used for columns.

What is the lambda_1 reference slenderness? lambda_1 = 93.9 epsilon is the slenderness value at which the Euler buckling stress equals the yield stress (pi x sqrt(E/fy)). With fy = 235 MPa, lambda_1 = 93.9. With S355, epsilon = sqrt(235/355) = 0.814, so lambda_1 = 76.4. The non-dimensional slenderness lambda_bar = (L_cr/i)/lambda_1 ensures columns of all steel grades are compared on a consistent basis.

How do I choose between HEA and HEB for my column? HEA sections have wider flanges relative to their depth (h/b ~ 1.0) which gives better weak-axis buckling resistance. HEB sections have even wider flanges (h/b ~ 1.0, but deeper overall) and approximately 80% higher cross-sectional area than the equivalent HEA. Choose HEA for medium axial loads (400-1500 kN) where minor-axis buckling may govern. Choose HEB for heavy axial loads (1500+ kN) or where both axes are similarly restrained. For lighter loads (200-800 kN), IPE sections provide the most mass-efficient solution.

Educational reference only. Design per EN 1993-1-1:2005 + A1:2014. Verify against current Eurocodes and National Annex values. Results are PRELIMINARY — NOT FOR CONSTRUCTION without independent Chartered Engineer verification.