| 摘要: |
| 为研究在电场和低温共同作用下镁盐及硫酸盐对水泥基材料的侵蚀行为，利用外观破坏等级、抗压强度比以及SEM/EDS，FTIR和XRD等手段分析了其侵蚀机理.结果表明：在电场作用下，阴极Na2SO4溶液阳极MgSO4溶液电极组合在侵蚀120d时的侵蚀效果最明显，其次是阴极MgSO4溶液阳极MgSO4溶液电极组合和阴极MgSO4溶液阳极MgCl2溶液电极组合；在阴阳极均存在镁盐时，水泥基材料的侵蚀劣化程度反而不及阳极单独存在镁盐时严重；当阴极存在镁盐时，由于阴极附近的水在电场作用下被电解而使阴极区域聚集了更多的OH-与镁盐生成沉淀Mg(OH)2，Mg(OH)2在侵蚀初期会堵塞试件表面从而延缓SO2-4的迁入，随着侵蚀龄期的增加，积累的镁盐开始腐蚀C S H凝胶并造成试件开裂，继而加速试件侵蚀. |
| 关键词: 电场 水泥基材料 硫酸盐 镁盐 碳硫硅钙石 |
| DOI：10.3969/j.issn.1007 9629.2016.06.008 |
| 分类号: |
| 基金项目:国家自然科学基金面上项目(51572038) |
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| Effect of Different Magnesium Salts and Sulfates on Thaumasite Sulfate Attack of Cement Based Materials under Electrical Field and Low Temperature |
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LUO Yaoling, WANG Chong, PENG Xiaoqin, YU Chao
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College of Materials Science and Engineering, Chongqing University, Chongqing 400045, China
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| Abstract: |
| The magnesium salt and sulfate attack of cement based materials under electrical field and low temperature environment was studied by corrosion damage grade of TSA, compressive strength ratio, SEM/EDS, FTIR and XRD. The results indicate that cement based materials are significantly corroded in a cathode Na2SO4 anode MgSO4 compound， the next was in a cathode MgSO4 anode MgSO4 compound and cathode MgSO4 anode MgCl2 compound. The corrosion of magnesium salts in both cathode and anode is inferior to the case where magnesium salts does not exist in cathode. The water was electrolyzed to OH- reaction with magnesium salt to Mg(OH)2 under the electrical field of cathode when there was magnesium salt in cathode. Mg(OH)2 will jam the surface of sample which results in delaying the migration of SO2-4 and magnesium salt would continuously corrode C S H gel which results in the production of surface crack to accelerate the corrosion of cement based materials. |
| Key words: electrical field cement based material sulfate magnesium salt thaumasite |
