膨胀剂对粉煤灰混凝土显微结构及抗碳化性能的影响  

Effect of expansive admixture on the microstructure and carbonation resistance of fly ash concrete

作　　者：水中和[1] 屠柳青[1,2] 马军涛[1] 陈伟[1] 徐文冰[1] 

机构地区：[1]武汉理工大学材料科学与工程学院,湖北武汉430070 [2]中交武汉港湾工程设计研究院有限公司,湖北武汉430071

出　　处：《混凝土》2011年第7期62-64,68,共4页Concrete

基　　金：国家自然科学基金(50802067);中央高校基础研究基金(2010-VI-011);教育部回国留学人员基金

摘　　要：在水泥混凝土中加入膨胀剂将改变水化产物的数量和孔结构,进而影响其抗碳化性能。对掺膨胀剂水泥混凝土的显微结构及抗碳化性能进行了研究,分析了膨胀剂用量和碳化过程对混凝土中Ca(OH)2含量和孔结构特性的改变规律。研究结果表明:膨胀剂虽然增加了混凝土内Ca(OH)2的数量,但同时劣化了混凝土内部的孔结构,使CO2更易向混凝土内部渗透,从而加速了混凝土的碳化。The addition of expansive admixture in concrete can change both the density and alkalinity, thereby affect the carbonation resistance. Expansive admixture is used in this article,which studied how different additions of expansive admixture influence the carbonation rate of concrete.The mechanism was discussed from two aspects including alkali reserve and pore structure.The results showed that expansive admixture could both increase the alkali reserve and coarsen the structure of concrete, then accelerated the diffusion rate of C02 ultimately.

关 键 词：膨胀剂 碳化速率 碱含量 孔结构 

分 类 号：TU528.042.4[建筑科学—建筑技术科学]