Experimental and numerical investigation on Local–Overall interactive buckling behavior of welded I-Section steel columns

Abstract A comprehensive experimental and numerical investigation of the interactive buckling behavior of welded I-section steel columns was undertaken. The experimental program employed 16 welded I-section columns made of Q235B or Q345B steel and included material tensile coupon tests, column tests, and initial geometric imperfection measurements. The specimens were selected to cover a wide range of width-to-thickness ratios and slendernesses. Comparisons between the test results and current specifications Eurocode 3 and ANSI/AISC 360–16 were presented, and the accuracy of the specifications was evaluated. In conjunction with the experimental program, a finite element (FE) model was used to replicate the tests. FE models considering initial imperfections and material nonlinearity were established and the reliability of the modeling methodology was verified by test results. On the basis of the calculation results, a design proposal for both normal and high strength steel is presented. Comparisons of the FE results with the predictions by the design provisions revealed that the new design proposal is more accurate than the current specifications.