金笠梅·奥斯曼,达斯纳穆迪·苏达

硫酸盐对混凝土结构的侵蚀影响了混凝土的耐久性，其中混凝土与海水、沼泽水、地下水、污水、淡水等相互作用。在这项研究中，飞灰（FA）和纳米粒子等辅助胶凝材料被一起纳入常规混凝土，旨在增强混凝土对硫酸盐渗透的抵抗力。目前的工作重点是了解通过表面硫酸盐侵蚀用纳米粒子改性的FA混凝土的降解。混凝土混合物如FA和用2 wt %纳米二氧化钛（FAT）、纳米碳酸钙（FAC）和纳米二氧化钛与纳米碳酸钙（FATC）比例为1：1改性的FA。样品暴露在3%的硫酸铵和硫酸钠中90天。本文对所有试件的劣化效应和微观结构性能的变化进行了比较研究。结果表明，与FA混凝土相比，FAT、FAC和FATC混凝土在硫酸铵和硫酸钠溶液中已经劣化。用飞灰部分替代水泥会减少可自由利用的活性铝酸盐的数量。飞灰消耗游离石灰可防止与硫酸盐发生反应。粉煤灰混凝土抗硫酸盐侵蚀的增强性能可以通过减少C3A含量来实现，从而减少可用的Ca（OH）2并降低有害钙矾石和石膏形成的可能性。

具体的；粉煤灰；纳米粒子；硫酸盐侵蚀；恶化

[1] Bilodeau A, Sivasundaram V, Painter KE, Malhotra VM (1994) Durability of concrete incorporating high volumes of fly ash. U.S. ACI Mater J 91:3–12. [2] Hooton RD (1993) Influence of silica fume replacement of cement on physical properties and resistance of sulfate attack, freezing andthawing, and alkali silica reactivity. ACI Mater J 90:143–151. [3] Jianming G, Zhenxin Y, Luguang S (2013) Durability of concrete exposed to sulfate attack under flexural loading and drying–wetting cycles. Constr Build Mater 39:33–38. [4] Jin ZQ, Sun W, Zhang YS, Jiang YS, Lai YZ (2007) Interaction between sulfate and chloride solution attack of concretes with and without fly ash. Cem Concr Res 37:223–1232. [5] Sudha U, George RP, Vishwakarma V, Ramachandran D, Thinaharan C, Viswanathan K, Kamachi Mudali U (2018) Surface modification of fly ash concrete through nanophase incorporation for enhanced chemical deterioration resistance. J Bio Tribo Corros 4:1–10. [6] Tao JT (2005) Preliminary study on the water permeability and microstructure of concrete incorporating nano-SiO2. Cem Concr Res 35: 1943–1947. [7] Tikalsky PJ and Carrasquillo RL (1989). The effect of fly ash on the sulfate resistance of concrete , Center for Transportation Research, Bureau of Engineering Research. The University of Texas at Austin, Research Report 481–5. [8] Uthaman S, George RP, Vinita V, Ramachandran D, Thinaharan C, Viswanathan K, Kamachi Mudali U (2018) Surface modification of fly ash concrete through nanophase incorporation for enhanced chemical deterioration resistance. J Bio-and Tribo-Corrosion 4:1–10.

点击下载PDF