碳酸盐溶液中富水充填材料的腐蚀及劣化机理  

Corrosion and deterioration mechanism of water-rich filling materials in carbonate solutions

作　　者：高萌[1] 刘娟红[1] 吴爱祥[1] 

机构地区：[1]北京科技大学土木与环境工程学院,北京100083

出　　处：《工程科学学报》2015年第8期976-983,共8页Chinese Journal of Engineering

基　　金：国家自然科学基金资助项目(51374036);'十二五'国家科技支撑计划资助项目(2012BAB08B02)

摘　　要：为了研究碳酸根离子对富水充填材料的影响,通过强度检测、扫描电镜观察、X射线衍射分析和红外光谱测试,分析富水充填材料在碳酸钠溶液中浸泡后的宏观及微观结构变化,并对其腐蚀及劣化机理进行探讨.富水充填材料在质量分数为10%的碳酸钠溶液中浸泡后,抗压强度随浸泡时间延长大幅度降低,浸泡90 d后抗压强度比标养28 d抗压强度降低72.5%,浸泡28 d后出现泥化现象.X射线衍射图谱显示,富水充填材料在质量分数为10%的碳酸钠溶液中浸泡后有碳硫硅钙石生成,且随浸泡时间延长碳硫硅钙石的生成量增大.红外光谱结果未发现[Al O6]存在,证实在碳酸钠溶液中富水充填材料硬化体中钙矾石急剧减少,转变为烂泥状的碳硫硅钙石;碳硫硅钙石作为无胶结力物质,会对富水充填材料硬化体造成严重破坏,表明碳酸盐溶液对富水充填材料具有腐蚀作用.In order to research the impact of carbonate ions on water-rich filling materials,strength testing,scanning electron microscopy,X-ray diffraction analysis and IR spectrum testing were used to analyze the macro-and micro-structural change and the corrosion and deterioration mechanism of the materials in sodium carbonate solutions. It is found that the compressive strength of the materials in a sodium carbonate solution whose mass fraction is 10% decreases significantly with increasing soaking time. When the soak age is 90 d,the compressive strength of the materials decreases by 72. 5% compared with standard curing for 28 d. After soaking for 28 d the specimen surface is muddy. XRD patterns show that after soaking in a sodium carbonate solution whose mass fraction is10%,thaumasite generates in the materials. With increasing soaking time the amount of thaumasite increases. Infrared spectroscopy results show that there does not exist [Al O6]. This confirms that ettringite in the materials soaking in the sodium carbonate solution drastically reduces and transforms into pulpy thaumasite. As non-cemented materials,thaumasite will cause serious damage to the hardening body of the materials. This shows that the carbonate solution has corrosive action on water-rich filling materials.

关 键 词：充填材料 硫铝酸盐 碳酸盐 腐蚀 劣化 

分 类 号：TD823.7[矿业工程—煤矿开采]