粉煤灰混凝土抗碳化性能及显微硬度分析  

Carbonation of Fly Ash Concrete and Mircro-hardness Analysis

作　　者：陈伟[1] 田亚坡[1] 周紫晨[1] 

机构地区：[1]武汉理工大学材料科学与工程学院,武汉430070

出　　处：《武汉理工大学学报》2009年第11期48-51,共4页Journal of Wuhan University of Technology

基　　金：国家自然科学基金(50802067)

摘　　要：研究了碳化时间、粉煤灰掺量和水胶比对粉煤灰高性能混凝土抗碳化反应能力的影响,运用显微分析方法研究了碳化反应改变水泥浆体及界面过渡区特性的规律。结果表明,用粉煤灰取代高性能混凝土中的水泥导致混凝土早期抗碳化能力下降,而后期抗碳化能力有一定程度的提升;粉煤灰高性能混凝土的抗碳化性能随水胶比的减小而提高;碳化反应可以提高水泥浆体及混凝土界面过渡区的显微硬度和密实程度。当粉煤灰掺量较小时,碳化反应可以减小混凝土界面过渡区的宽度。The effects of carbonation age, fly ash content in the binder and the water to binder ratios on the carbonation . depth of fly ash concrete is investigated and the micmmechanical properties of the hardened paste and the inter facial transition zone is analyzed with the micro-hardness method. The experimental results show that replacing Portland cement in concrete with fly ash increases the carbonation rate at early ages, while the late age carbonation rate is lowered. Decreasing the water to binder ratios of concrete enhances the carbonation resistance of concrete. Micromechanical analysis shows that the carbonation reaction increases the micro-hardness of the paste and the compactness of the ITZ. For the relative low replacement levels, the width of the ITZ is reduced if the concrete is carbonated.

关 键 词：粉煤灰混凝土 碳化反应 界面过渡区 显微结构 显微硬度 

分 类 号：TU528.041[建筑科学—建筑技术科学]