A New Simple Method for the Strength of High-Strength Steel Thin-Walled Box Columns Subjected to Axial Force and Biaxial End Moments

الملخص EN

The strength of Q460 steel welded thin-walled box columns under biaxial bending is investigated by an FE model.

The numerical results, together with available experimental data, are compared with the American Specification ANSI/AISC 360-10.

It shows that ANSI/AISC 360-10 provides a good estimate over a wide range of column slenderness ratios; but it severely underestimates the strengths of beam-columns with large slenderness ratios and slightly underestimates those of beam-columns made from HSS with fy = 741 MPa, and the calculation is more complicated because of using an effective width concept.

Therefore, a simple and effective calculation method is proposed.

Also, a comparison is made between the proposed formulas and the available experimental results.

It shows that the proposed formulas can precisely evaluate the local-overall interactive buckling strength of HSS beam-columns and, in most cases, are also suitable for beam-columns fabricated from mild steels.

The proposed formulas are simple and, meanwhile, achieve the same level of accuracy as ANSI/AISC 360-10.