Flexural buckling behavior of corroded hot-rolled H-section steel beams

摘要

This paper mainly investigates the flexural buckling behavior of corroded hot-rolled H-section steel beams under four-point bending. A total 43 observations comprising of five experiments and thirty-eight numerical analysis results were reported to investigate the corrosion types, degrees and locations on the initial imperfections, failure modes and the flexural buckling behavior of steel beam. Based on the analysis, a recommended formula of the flexural buckling strength of corroded steel beams is derived using the direct strength method. The results show that the tested specimens fail with the local buckling of upper flange and web near the mid-span, but the failure positions and the buckling half-wavelength are different with corrosion degrees. The results also show that the yield load, buckling load and ultimate load of tested specimens decrease with the corrosion degrees increasing. When the corrosion ratio reaches 16.88%, the yield load decreases at a ratio of 21.4%, the critical buckling load decreases by 33.2%, the ultimate load after buckling decreases at a ratio of 28.3%, and the ductility coefficient decreases by 59.4%. Finally, the comparison between predicted and actual flexural strength indicates that the proposed formula can calculate the flexural buckling capacity of corroded H-section steel beams with varying degrees of corrosion.