Lateral-Torsional Buckling Performance of High Strength Steel Welded I-Section Beam-Columns

High strength steel (HSS) members are increasingly employed in contemporary buildings, owing to favorable mechanical properties. However, the smaller required cross section sizes benefitting from high yield strength conversely highlight buckling problems of HSS members. In the present work, the study on lateral-torsional buckling (LTB) of HSS beam-columns of various steel grades under uniform bending moment was operated numerically. The FE models of HSS beam-columns were validated against eigenvalue buckling analysis and existing test data. The application of existing codified design standards for LTB of HSS beam-columns was examined. The effects of slenderness, section geometric characteristics and steel grades were parametrically analyzed. An alternative interactive formula for resistance prediction of HSS welded I-section beam-column LTB was proposed based on plate-beam theory.