超高性能海水海砂混凝土的硫酸盐腐蚀破坏机理研究  

Corrosion Failure Mechanism of Ultra-high-performance Concretes Prepared with Sea Water and Sea Sand in an Artificial Sea Water Containing Sulfate

作　　者：李田雨 王维康 李扬涛 包腾飞[1] 赵梦凡 沈欣欣 倪磊 马庆磊[4] 田惠文[5] LI Tianyu;WANG Weikang;LI Yangtao;BAO Tengfei;ZHAO Mengfan;SHEN Xinxin;NI Lei;MA Qinglei;TIAN Huiwen(College of Water Conservancy and Hydropower Engineering,Hohai University,Nanjing 210098,China;School of Water Resources and Hydropower Engineering,Wuhan University,Wuhan 430070,China;Nantong Academy of Building Research Co.,Ltd.,Nantong 226000,China;Jiangsu Jinling Special Coatings Co.,Ltd.,Yangzhou 225212,China;Key Laboratory of Marine Environmental Corrosion and Bio-Fouling,Institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071,China)

机构地区：[1]河海大学水利水电学院,南京210098 [2]武汉大学水利水电学院,武汉430070 [3]南通市建筑科学研究院有限公司,南通226000 [4]江苏金陵特种涂料有限公司,扬州225212 [5]中国科学院海洋研究所海洋环境腐蚀与生物污损重点实验室,青岛266071

出　　处：《中国腐蚀与防护学报》2023年第5期1101-1110,共10页Journal of Chinese Society For Corrosion and Protection

基　　金：江苏省卓越博士后计划;江苏省科技厅科技项目基础研究计划自然科学基金(SBK2023040182);江苏省土木建筑学会科研课题。

摘　　要：使用海水和海砂制备超高性能混凝土,并以淡水河砂制备的超高性能混凝土进行对比。在开展硫酸盐侵蚀作用下腐蚀破坏规律研究的基础上,采用压汞法、扫描电子显微镜、能谱仪和X射线衍射仪技术揭示了两种混凝土在硫酸盐侵蚀作用下的损伤机制并总结了其损伤机理。随着硫酸盐侵蚀的发展,混凝土表层的水泥石与Mg^(2+)和SO_(4)^(2-)反应生成钙矾石以及石膏等硫酸盐腐蚀产物,大量腐蚀产物的出现一方面消耗了Ca(OH)_(2)和C-S-H凝胶等水化产物,另一方面使混凝土表面的水泥石失去强度和胶结力,进而出现脱落的现象。混凝土表层的溶蚀,暴露出了位于表层区域的集料和钢纤维,钢纤维接触到环境中的H_(2)O发生了锈蚀。随着硫酸盐腐蚀的进行,暴露在环境中的混凝土表面进一步加快了AFt以及石膏等硫酸盐腐蚀产物的生成,造成失去强度的砂浆与混凝土表面的钢纤维一起脱落,暴露出内部并形成新的混凝土外表面。区别于传统的3种硫酸盐腐蚀破坏形式,超高性能混凝土的硫酸盐腐蚀破坏形式更加复杂,但这些破坏特征均只发生在混凝土表层毫米级的范围内,混凝土内部仍保持着优异的力学与耐久性特征,对混凝土结构的整体影响较小,两种混凝土展现出优异的抗硫酸盐侵蚀性能。Sulfate is one of the main components of sea water.Concrete structures serving in marine environment may come into contact with sea water,thereby,a series of sulfate induced chemical reactions occurred to cause the destruction of concrete.According to the characteristics of corrosion products,the sulfate induced corrosion attacks may be divided into the following three types,i.e.,ettringite sulfate attack,gypsum sulfate attack and carbonite sulfate attack.In this paper,the corrosion behavior of the ultra-high-performance concretes prepared with sea water and sea sand(SSUHPC),as well as those with fresh water and river sand(FRUHPC)were comparatively studied in an artificial sea water containing sulfates.Based on the study of the evolution of sulfate induced corrosion degradation process,the corrosion damage mechanism related with SSUHPC and FRUHPC was revealed by using MIP,SEM-EDS and XRD techniques,and the damage mechanism was summarized.With the progress of sulfate corrosion process,the cementite on the surface of concrete reacts with Mg^(2+)and SO_(4)^(2-) to produce corrosion products such as AFt and gypsum sulfate etc.On the one hand,the formation of a large number of corrosion products may consume hydration products such as Ca(OH)_(2) and C-S-H gel;on the other hand,the cementite on the surface of concrete loses strength and cementation,and then falls off.Due to the corrosion damage of the concrete surface layer,the aggregates and steel reinforce bars within the concrete are exposed,therewith,the steel bars will rust once they come into contact with the corrosive fluids within the environment.With the progress of sulfate corrosion,the formation of corrosion products Aft,gypsum sulfate etc.is speeded,and which cumulated on the exposed concrete surface.Hence,the mortar that loses strength falls off together with the steel bars from the concrete surface,so that to further expose the interior of the concrete,which in turn,act as a“new outer surface”of the concrete faced to the corrosive environment.Different

关 键 词：海砂 超高性能混凝土 硫酸盐腐蚀 微观结构 损伤机理 

分 类 号：TD123[矿业工程—矿山地质测量]