珊瑚礁砂制备超高性能混凝土的可行性研究  

Feasibility study on preparation of ultra high performance concrete with coral reef sand

作　　者：陈飞翔[1,2,3] 陈尚雷 张国志 杨荣辉[1,2,3] CHEN Feixiang;CHEN Shanglei;ZHANG Guozhi;YANG Ronghui(CCCC Second Harbor Engineering Co.,Ltd.,Wuhan 430040,China;Key Laboratory of Large-span Bridge Construction Technology,Wuhan 430040,China;CCCC Highway Bridge National Engineering Research Centre Co.,Ltd.,Wuhan 430040,China)

机构地区：[1]中交第二航务工程局有限公司,湖北武汉430040 [2]长大桥梁建设施工技术交通行业重点实验室,湖北武汉430040 [3]中交公路长大桥建设国家工程研究中心有限公司,湖北武汉430040

出　　处：《混凝土》2020年第7期65-69,共5页Concrete

基　　金：国家“十三五”科技支撑计划子课题(2016YFC0701003-04):海砂混凝土在海洋建筑工程中的应用示范。

摘　　要：在远海工程施工过程中可利用珊瑚礁砂替代石英砂制备超高性能混凝土。通过研究胶凝材料与珊瑚礁砂的比例和珊瑚礁粉取代珊瑚礁砂的比例,并测试其力学性能、耐久性和微观结构后,得出结论如下:珊瑚礁砂超高性能混凝土的最佳胶砂比为1∶1,珊瑚礁粉的最佳取代比例为30%,28 d抗压强度为137 MPa,28 d抗折强度为27 MPa,电通量为97 C,氯离子扩散性系数为30×10-14 m2/s,可完全满足超高性能混凝土的指标要求。珊瑚礁砂超高性能混凝土的水化产物与普通混凝土并无太大差异,都水化生成了Ca(OH)2,AFt和C-S-H凝胶,并相互交错形成密实的结构,同时在界面过渡区很难发现结晶完好的六方板状Ca(OH)2晶体。In the construction process of the offshore project,coral reef sand can be used instead of quartz sand to prepare ultra-high performance concrete.By studying the ratio of cementitious materials to coral reef sands and the proportion of coral reef powder replacing coral reef sands,and testing their mechanical properties,durability and micro-structure,the conclusions are as follows:the best ratio of cementitious materials to coral reef sands is 1∶1,the best replacing ratio of coral reef powder is 30%,28 d compressive strength is 137 MPa,28 d flexural strength is 27 MPa,electric flux is 97 C,chloride ion diffusivity is 30×10-14 m2/s,which fully meet the index requirements of ultra high performance concrete.The hydration produces Ca(OH)2,AFt and C-S-H gels,which are interlaced to form a dense structure,and it is difficult to find crystallized hexagonal plate-like Ca(OH)2 crystals in the interfacial transition zone.

关 键 词：珊瑚礁砂 超高性能混凝土 力学性能 耐久性 微观结构 

分 类 号：TU528.041[建筑科学—建筑技术科学]