Numerical investigation into high strength Q690 steel columns of welded H-sections under combined compression and bending

In conjunction with the experimental investigation described in the paper [1], a numerical modeling programme has been carried out to investigate further the structural behaviour of high strength Q690 steel columns of welded H-sections under combined compression and bending. Finite element (FE) models were developed by using the FE package ABAQUS. Geometrical and material non-linearities were incorporated in the FE models. Through the validation against the experimental results, these FE models showed excellent capability of replicating the key test results, including failure modes, failure loads and full load-axial deformation and load-lateral deflection histories. Upon validation of the FE models, parametric studies were conducted focusing on the effect of member residual stresses and material yield to tensile strength ratios. Then a large number of FE models were established to generate additional structural performance data over a wide range of cross-section dimensions, member slenderness and initial loading eccentricity ratios. The FE model results were then compared with the design buckling resistances of columns under combined compression and bending according to the current European Standard EN 1993-1-1, American Specification ANSI/AISC 360-16 and Chinese Standard GB 50017-2003. The comparisons revealed that by properly selecting design parameters, the design rules in EN 1993-1-1 and GB 50017-2003 could provide close and safe predictions to the buckling resistances of Q690 steel columns of welded H-sections while the design rules in ANSI/AISC 360-16 was readily applicable to the design of Q690 steel columns of welded H-sections.