粉煤灰水泥石碳化性能的化学分析  

Chemical Analysis of Carbonation of Fly Ash Blended Cement Pastes

作　　者：万朝均[1] 张廷雷[1,2] 陈璐圆[1,3] 夏建民[1,4] 李有光[1,5] 

机构地区：[1]重庆大学材料科学与工程学院,重庆400045 [2]中铁二院工程集团有限责任公司,成都610031 [3]东南大学材料科学与工程学院,南京211189 [4]中交第二航务工程局有限公司西南(昆明)分公司,昆明650224 [5]重庆润江水泥有限公司,重庆404000

出　　处：《硅酸盐学报》2012年第8期1102-1111,共10页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金(50772136);重庆市科技攻关计划(CSTC;2008AB7113)资助项目

摘　　要：开发了一种自制测量装置。利用该装置,沿碳化深度方向,分层测定了碳化粉煤灰水泥石中CaCO3的含量。绘制了"CaCO3含量–深度"曲线。根据曲线特点,定义了完全碳化区、部分碳化区、未碳化区等概念和碳化程度、碳化速度等特征指标。研究了粉煤灰掺量、水胶比、龄期、养护条件、碳化前烘干处理、碳化时间、碳化湿度等对粉煤灰水泥石碳化性能的影响。结果表明:粉煤灰掺量越大,水胶比越高,龄期越短,养护环境越干燥,碳化前试件越干燥,粉煤灰水泥石的抗碳化性能越差;碳化时间越长,碳化湿度越低,粉煤灰水泥石的碳化程度越高;但碳化速度随碳化时间的增长而减慢。这些结论与文献报道的用其他方法得到的公认的结论一致。本方法还得到了更加深入的研究结果,即:粉煤灰掺量越大、粉煤灰水泥石中可碳化物质的相对含量越低;水胶比、龄期、养护条件、碳化时间、碳化湿度基本不改变粉煤灰水泥石中可碳化物质的相对含量;龄期、养护条件可改变未碳化粉煤灰水泥石中碳酸盐的相对含量。An exclusive measuring installation was developed. By using the installation, the content of calcium carbonate in carbonating fly ash blended cement pastes was measured in each layer along the direction of carbonation. Curves of the content of calcium carbonate as a function of depth was obtained. Based on the characteristics of the curves, concepts of fully carbonated zone, partially carbonated zone and uncarbonated zone, etc. and characteristic indexes of carbonation degree, carbonation rate, etc were defined. The influences of percentage of fly ash, water to binder ratio, age, curing condition, drying treatment prior to carbonating, carbonation time, and carbonating humidity, etc. on the carbonation of fly ash blended cement pastes were investigated. The results indicated that the carbonation resistance of fly ash blended cement pastes decreased with the increasing of percentage of fly ash, water to binder ratio, the decreasing of age, the lack of water when curing, the less moisture of specimens before carbonation. The degree of carbona- tion increased with the carbonation time and the decreasing of carbonation humidity. The carbonation rate decreased with duration time of carbonation. These conclusions are consistent with those widely accepted conclusions from other existing methods reported in published papers. Furthermore, from this method, some deeper insights were obtained： 1） The percentage of carbonatable constituents of the fly ash blended cement pastes decreased with the increasing of percentage of fly ash; 2） Water to binder ratio, age, curing con- dition, carbonation time, and carbonating humidity had little influence on the percentage of carbonatable constituents of the fly ash blended cement pastes; The percentage of carbonate of the uncarbonated area of fly ash blended cement pastes could be changed by the age and curing condition.

关 键 词：碳酸钙 水泥石 粉煤灰 碳化 相对湿度 

分 类 号：TQ172[化学工程—水泥工业]