钢筋坑蚀对混凝土梁抗弯性能的影响

Effect of pitting corrosion on flexural performance of RC beams

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MonteCarlo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。

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 has a significant effect on flexural performance of component. It was proved that the 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.