多区域局部腐蚀圆钢管混凝土轴压构件受力性能研究

Localized corrosion can occur on the outer surface of the concrete-filled steel tube (CFST) which can significantly compromise the safety of the structure during service. Localized corrosion can occur on multi-regions of members, with each region exhibiting irregular shapes and uneven surfaces, and the spatial distribution has great randomness. To investigate the influence of the multi-region localized corrosion on the axial compression behavior of circular CFST, a numerical analysis was conducted based on ABAQUS software in this study. The established numerical models were first verified and then extended to take the random characteristics of multi-region localized corrosion in terms of shape, surface, and spatial locations into account. The influence of irregular shape, uneven surface, and random spatial locations along the circumferential and longitudinal directions of multi-region corrosion on the ultimate strength was investigated through parametric analysis. It is found that the multi-region random localized corrosion can be simplified as the corresponding regular defect with constant depth. The random corrosion locations have a great influence on the ultimate strength and the controlling section of CFST is influenced by the location of localized corrosion. Based on the parametric analysis, a calculation method was proposed to determine the ultimate strength of CFST with multi-region localized corrosion, utilizing the controlling section. The difference between the calculated and numerical results is within 5% and reasonable accuracy is achieved.