全珊瑚混凝土中钢筋锈蚀的氯离子阈值研究  

Determination of Chloride Threshold Value in Reinforced Coral Aggregate Concrete

作　　者：吴彰钰 余红发 麻海燕 达波 WU Zhangyu;YU Hongfa;MA Haiyan;DA Bo(Civil Aviation College, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China;College of Harbour, Coastal and Offshore Engineering, Hohai University, Nanjing 210098, China)

机构地区：[1]南京航空航天大学民航学院,江苏南京210016 [2]河海大学港口海岸与近海工程学院,江苏南京210098

出　　处：《建筑材料学报》2020年第5期1078-1085,1092,共9页Journal of Building Materials

基　　金：国家自然科学基金资助项目(51878350,11832013,51678304);中国博士后科学基金资助项目(2018M630558);江苏省自然科学基金资助项目(SBK2018041341);江苏省研究生科研创新计划资助项目(KYCX20_0212)。

摘　　要：基于线性极化电阻(LPR)法和混凝土“Ⅱ维氯离子扩散理论”模型,针对埋置不同种类钢筋的全珊瑚混凝土(CAC)试件进行270d的暴露试验,得到CAC试件中钢筋的腐蚀速率(i)和表面自由氯离子含量(Csf)值,并确定了钢筋锈蚀的氯离子阈值(CTV)取值范围.结果表明:随着混凝土保护层厚度的增大,CAC试件中钢筋的腐蚀电位逐渐正移,腐蚀电流逐渐减小,钢筋的锈蚀概率和腐蚀速率均逐渐降低;相同条件下,CAC试件中不同种类钢筋的耐蚀性能由强到弱依次为:2205双相不锈钢筋(2205S)>316L不锈钢筋(316L)>有机新涂层钢筋(OCS)>普通钢筋(OS);根据钢筋Csf与i之间的关系,得到OCS、316L和2205S的CTV取值范围,分别为小于0.210%、0.330%~0.410%和大于0.463%.Corrosion rate of steel embedded in coral aggregate concrete(CAC)exposed in simulated seawater for 270days and its surface free chloride(Csf)values were determined by linear polarization resistance(LPR)method and two-dimensional chloride diffusion model.The chloride threshold value(CTV)of different types of steels in CAC was determined by the relationship between the Csf and its corrosion rate.The results indicate that the corrosion rate of steel in CAC gradually decreases with the increase of cover thickness and the anti-corrosion performances of them is ranked as follows:2205duplex stainless steel(2205S)>316L stainless steel(316L)>organic coated steel(OCS)>ordinary steel(OS).And the CTV values of them in CAC are determined as follows:Less than 0.210%(OCS),0.330%0.410%(316L)and more than 0.463%(2205S).

关 键 词：全珊瑚混凝土 钢筋锈蚀 氯离子阈值 Ⅱ维氯离子扩散理论模型 线性极化 

分 类 号：TU528[建筑科学—建筑技术科学]