【摘要】 在服役期间，钢管混凝土的外部钢管极易发生局部腐蚀，严重危害结构的安全性。局部腐蚀可分布在构件表面的多个区域，腐蚀区域具有随机的几何形貌，具体表现为不规则形状和不均匀表面，其空间分布也具有很强的任意性。为了研究多区域局部腐蚀对圆钢管混凝土构件轴压性能的影响，采用ABAQUS有限元软件建立并验证了单块局部腐蚀圆钢管混凝土构件有限元模型，之后建立了考虑多区域局部腐蚀分布位置随机性以及腐蚀形貌随机性的有限元分析模型。分析了多区域局部腐蚀不规则形状和不均匀表面、沿构件环向和纵向的相对位置对圆钢管混凝土构件轴压承载力的影响。结果表明：具有随机形貌的多区域局部腐蚀可以简化为对应位置上的腐蚀深度恒定的矩形腐蚀区域；多区域局部腐蚀的随机分布位置对构件轴压承载力具有显著影响，腐蚀分布的位置会影响构件的控制截面。根据参数分析结果，提出了基于控制截面的多区域局部腐蚀圆钢管混凝土构件轴压承载力计算方法，计算结果与参数分析结果误差基本小于5%,吻合较好。更多还原

【Abstract】 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.更多还原