弯曲荷载与氯盐耦合作用下混凝土中钢筋锈蚀程度评估  

EVALUATION OF STEEL CORROSION IN CONCRETE UNDER SIMULTANEOUS FLEXURAL LOAD AND CHLORIDE ATTACKS

作　　者：施锦杰[1] 孙伟[1] 

机构地区：[1]东南大学材料科学与工程学院江苏省土木工程材料重点实验室,南京211189

出　　处：《硅酸盐学报》2010年第7期1201-1208,共8页Journal of The Chinese Ceramic Society

基　　金：国家"973"计划:环境友好现代混凝土的基础研究(2009CB-623200)项目资助

摘　　要：在实际工程中,钢筋混凝土中的钢筋是在氯盐侵蚀和外荷载耦合作用下服役并劣化的。重点研究了氯盐侵蚀和外荷载耦合作用对加速钢筋锈蚀的规律和机理,系统测试了在耦合作用下钢筋腐蚀速度并预测了混凝土保护层开裂时间。试件为内置4根钢筋的混凝土棱柱(普通钢筋混凝土试件和矿渣取代20%水泥的高性能混凝土试件)。运用电化学方法(腐蚀电位、线性极化和电化学阻抗)对混凝土内的钢筋进行了腐蚀程度与状况试验。结果表明:在短期测试期内(8个月),弯曲荷载能明显增加普通混凝土试件中的钢筋锈蚀速度,缩短保护层开裂时间;而对于高性能混凝土试件,弯曲荷载作用则不甚明显。In practice,steel corrosion in concrete occurs under simultaneous load and chloride attacks.The effect of the simultaneous actions on the steel corrosion was investigated,and the corrosion rate of steel was examined.The time to corrosion-induced crack of concrete cover was also predicted.Concrete（i.e.,ordinary portland concrete（OPC） and high performance concrete（HPC） specimens with slag as a replacement of cement by 20% in mass） prisms were inserted with four embedded steel bars.Electrochemical methods（corrosion potential,linear polarization resistance and electrochemical impedance spectroscopy） were used to analyze the corrosion state of steel in concrete.The results show that the flexural load can increase the corrosion rate of steel in OPC specimens and reduce the time to corrosion-induced crack of concrete cover in short-term exposure（8 months）.However,the flexural load had a slight effect on the steel corrosion behavior in HPC specimens.

关 键 词：弯曲荷载 混凝土 钢筋锈蚀 锈蚀速度 氯盐侵蚀 

分 类 号：TU528[建筑科学—建筑技术科学]