自然扩散法测试混凝土氯离子扩散系数  

Natural diffusion method for testing chloride ion diffusion coefficient of concrete

作　　者：周莹 蔡景顺 石亮 ZHOU Ying;CAI Jingshun;SHI Liang(State Key Laboratory of High Performance Civil Engineering Materials,Jiangsu Research Institute of Building Science,Nanjing 210008,China;Jiangsu Sobute New Materials Co.,Ltd.,Nanjing 211103,China)

机构地区：[1]高性能土木工程材料国家重点实验室,江苏南京211100 [2]江苏苏博特新材料股份有限公司,江苏南京211103

出　　处：《混凝土》2020年第9期23-26,共4页Concrete

基　　金：国家重点研发计划(2017YFB0309904);国家重点基础研究发展计划(973)资助(2015CB655105);江苏省自然科学基金资助(BK20161101,BK20160104,BK20171111,BK20181127);中国电力工程顾问集团有限公司科技项目(DG1-T02-2017);中国铁路总公司科技项目(2017G007-C);工程项目(ZXGS-KJ-01);国家自然科学基金:NSFC-山东联合基金(U1706222);江苏省重点研发计划课题(BE2017158)。

摘　　要：分析比较了5种混凝土氯离子扩散系数测试方法的优缺点,选择自然扩散法进行混凝土氯离子扩散系数。采用电位滴定法测试混凝土中不同深度处氯离子含量,并借助菲克第二定律计算氯离子扩散系数,结果表明,混凝土中的氯离子含量与氯离子扩散系数均随着龄期的延长而增长,掺加侵蚀离子抑制剂后氯离子含量与扩散系数显著下降。氯离子进入混凝土后与水泥水化产物发生反应生成Friedel′s盐,固化氯离子,从而延长钢筋混凝土的使用寿命。The advantages and disadvantages of five kinds of concrete chloride ion diffusion coefficient test methods were analyzed and compared.The natural diffusion method was used to carry out the chloride ion diffusion coefficient of concrete.Potentioetric titration was used to test the chloride ion content at different depths in concrete,and the diffusion coefficient of chloride ion was calculated by Friedel′s second law.The results show that the chloride ion content and chloride ion diffusion coefficient in concrete increase with age.The chloride ion content and diffusion coefficient decreased significantly after the addition of the oxidative ion inhibitor.After entering the concrete,the chloride ions react with the cement hydration product to form Friedel′s salt,which solidifies the chloride ions,thereby prolonging the service life of the reinforced concrete.

关 键 词：混凝土 氯离子扩散系数 自然扩散法 

分 类 号：TU528.01[建筑科学—建筑技术科学]