EVALUATION OF MAXIMUM LOCAL BUCKLING STRESS OF I－SHAPED STEEL MEMBERS USING DIFFERENT STEEL GRADES FOR WEB AND FLANGES BASED ON FULL-SCALE STUB COLUMN COMPRESSION TESTS

The Built-up I-shaped steel members are fabricated from three steel plates: two flanges and one web. To fulfill design requirements, different steel grades may be used for the flanges and the web. This study focuses on built-up steel members with different tensile strengths between the flanges and the web. To clarify their local buckling behavior and deformation capacity, full-scale stub-column tests were conducted. In addition, mechanism models were proposed based on the yield line theory. The results show that the maximum strengths predicted by the proposed mechanism models agree well with the experimental results.