(1 中船第九设计研究院工程有限公司，上海 200063； 2 浙江大学结构工程研究所，杭州 310027)
［摘要］与钢筋均匀锈蚀相比，钢筋坑蚀具有显著的不确定性和截面损失等特点，对混凝土构件的抗弯性能具有一定的影响。结合国内外相关资料，通过实际工程中钢筋坑蚀的试验统计，验证了坑蚀系数服从极值I型的分布。基于钢筋的坑蚀概率模型，借助Monte Carlo模拟，分析了锈蚀钢筋混凝土梁的抗弯承载力，研究了钢筋坑蚀对混凝土受弯构件承载能力的影响。结果表明，钢筋坑蚀的随机性对梁的可靠性有很大影响，钢筋坑蚀构件抗弯承载力的下降速度比均匀锈蚀更快，对梁的耐久性具有潜在危害。
［关键词］坑蚀；不确定性；抗弯承载力；耐久性
Effect of pitting corrosion on flexural performance of RC beamsNi Guorong1, Jin Weiliang2, Zhu Weihua1, Song Zhigang2(1 China Shipbuilding NDRI Eng. Co.,Ltd.,Shanghai 200063,China;
2 Ins. of Stru. Eng.,Zhejiang Uni.,Hangzhou 310027,China)
Abstract:Pitting corrosion is one of the main manners of corrosion in reinforcement concrete (RC). Compared with general corrosion, the process of pitting corrosion shows more uncertainty and the reinforcement has greater section loss, which as a significant effect on flexural performance of component. It was proved thatthe Gumbel distribution is appropriate for modelling the pitting factor, by reference of correlative data and experimentation of practical reinforced bars. Based on probability model of pitting corrosion, Monte Carlo simulation method was introduced to analyze the effect of pitting corrosion on the flexural performance of RC beams. The results indicate that the randomicity of pitting corrosion has a great influence on the reliability of RC beams and the speed of induction of bending capacity of pitting corroded component is much higher than general corrosion, which has a potential hazard on the durability of RC beams.
Keywords:pitting corrosion; uncertainty; flexural capacity; durability
作者简介：倪国荣，硕士，工程师，Email:niguorong@126.com。
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