Performance of axially loaded slender circular CFSTs with random local corrosion

The performance of axially loaded slender circular concrete-filled steel tubes with random local corrosion was investigated in this paper through experimental and numerical study. Specifically, the randomness of corrosion included the random locations along the column height, irregular corrosion profile, and uneven corrosion surface. In the experimental study, machining defects are employed to simulate local corrosion, and five slender CFSTs were tested, with four containing the defect located at different member heights and one intact specimen. Additionally, a numerical study is conducted to consider the random nature of local corrosion in terms of random locations, irregular profiles, and uneven surfaces. A parametric analysis is then conducted, with varying parameters such as defect dimensions, locations, material strengths, steel ratio, and slenderness ratio. The analysis finds that the ultimate strength of the slender member is influenced by the location and dimensions of the local defect. Some sightly corrosion occurring in the column end has negligible influence on the performance of slender members. A method based on the controlled section is proposed for calculating the ultimate strength of slender circular CFSTs with random local corrosion, yielding accurate results.