钢筋锈蚀及混凝土劣化耦合对梁构件力学性能的影响  

Coupling effects of rebar corrosion and concrete deterioration on the flexural behavior of beam

作　　者：吴元周[1,2] 吕恒林[1,2] 方忠年[1] 温海燕[1] 孙雷[1] 

机构地区：[1]中国矿业大学力学与建筑工程学院,江苏徐州221116 [2]江苏建筑节能与建造技术协同创新中心,江苏徐州221116

出　　处：《中国矿业大学学报》2015年第5期793-799,共7页Journal of China University of Mining & Technology

基　　金：国家自然科学基金项目(51108451);江苏省自然科学基金项目(BK2008128);中国矿业大学大学生创新训练计划项目(X1029015307)

摘　　要：设计人工模拟环境,研究酸雾、氯盐及硫酸盐混合盐雾侵蚀以及碳化耦合作用下钢筋混凝土梁破坏模式、锈胀裂缝宽度、受弯承载力、荷载-挠度曲线,重点研究钢筋锈蚀与混凝土劣化耦合作用的影响.结果表明:钢筋锈蚀率低于3.27%时,试验梁基本没有锈胀开裂,受弯破坏模式主要为受压区混凝土压碎,极限承载力随锈胀裂缝宽度增加快速减小;锈胀裂缝产生后,破坏形式逐渐转变为受拉钢筋屈服破坏,且承载力随钢筋锈蚀率大幅增加而缓慢减小.荷载-挠度曲线的峰值和斜率随劣化程度增加而减小.钢筋锈蚀导致混凝土开裂,混凝土劣化降低对钢筋的约束,两者耦合加速黏结性能退化,从而导致梁构件力学性能退化.理论分析了试验现象产生的原因,并对试验结果和理论计算结果进行了验证.The failure modes,expansive crack width,flexural carrying capacity and load-deflection curves were studied based on the artificial environment.The coupling effects of rebar corrosion and concrete deterioration were focused on.The results show that expansive crack is not detected when the corrosion of rebar is below 3.27 percent,and the main failure mode is crushing of compressive concrete.The carrying strength decreases rapidly with the corrosion increasing.After the cracks appearing,the failure mode changes to the yield of rebar,but the carrying strength decreases slowly.As the deterioration of beams increasing,the peak value and slope of load-deflection reduce.The concrete cracks because of the corroded rebar,and the binding force of concrete to the rebar decreases.The coupling effects promote the degradation of the bond between them.And then the flexural behavior of beams decreases.The experimental phenomena was analyzed with theory,and the results of test and calculation were compared.

关 键 词：钢筋混凝土梁 锈蚀 劣化 耦合 受弯性能 

分 类 号：TU375.1[建筑科学—结构工程]