Abstract

The current paper provides modelling guidelines for nonlinear analysis and fragility assessment of corrosion-damaged reinforced concrete (RC) structures. A systematic guideline is proposed to model the adverse impact of corrosion on mechanical properties of steel and concrete materials including the negative impact of corrosion on inelastic buckling and low-cycle fatigue (LCF) degradation of reinforcing bars. The proposed fibre-based modelling technique is capable of simulating the spatial variability of localised corrosion and the influence of corrosion on damage states (DS). Corrosion-dependent pushover and cyclic analyses, incremental dynamic analyses (IDAs) and fragility analyses are carried out on three different case studies: (i) a cantilever square RC column, (ii) a cantilever circular RC column and (iii) a RC frame. The analyses results indicate that corrosion significantly affects the DS, sequence of failure mode, flexural capacity and energy dissipation capacity of RC structures. Moreover, alongside the corrosion, the geometry of RC components also affects their failure sequence, cyclic behaviour and energy dissipation capacity. It is shown that increasing degree of corrosion penetration results in the concentration of damage mainly in confined concrete.

摘要

目前的论文为腐蚀损坏的钢筋混凝土 (RC) 结构的非线性分析和脆弱性评估提供了建模指南。提出了一个系统的指导方针来模拟腐蚀对钢筋和混凝土材料的机械性能的不利影响，包括腐蚀对钢筋的非弹性屈曲和低周疲劳 (LCF) 退化的负面影响。所提出的基于纤维的建模技术能够模拟局部腐蚀的空间变化以及腐蚀对损伤状态 (DS) 的影响。腐蚀相关的推覆和循环分析、增量动态分析 (IDA) 和脆性分析在三个不同的案例研究中进行：(i) 悬臂方形 RC 柱，(ii) 悬臂圆形 RC 柱和 (iii) RC 框架. 分析结果表明，腐蚀对RC结构的DS、失效模式顺序、抗弯承载力和耗能能力有显着影响。此外，除了腐蚀之外，RC 组件的几何形状也会影响其失效顺序、循环行为和能量耗散能力。结果表明，腐蚀渗透程度的增加导致损伤主要集中在约束混凝土中。