复合胶凝材料的抗硫酸性能与腐蚀动力学分析

Resistance of Blended Cement Paste to Sulfuric Acid Attack and Corrosion Kinetics Analysis

通过硫酸浸泡腐蚀试验,研究矿粉单掺、硅灰-矿粉双掺2种复合胶凝材料体系的抗硫酸腐蚀性能.以质量损失、酸消耗量和腐蚀深度等为测试指标,研究了硬化水泥石在硫酸溶液中的劣化性能.结果表明,硫酸溶蚀水泥石形成的疏松腐蚀层可避免内部水泥石与酸直接接触,具有减缓酸腐蚀的作用.根据不同腐蚀时间的腐蚀深度建立了硬化水泥石的酸腐蚀动力学方程d=Ktn,d和t分别为腐蚀深度和腐蚀时间,K和n为试验拟合指数.据此可推算水泥石一定腐蚀时期的腐蚀深度,为混凝土结构设计、维修和防护等提供参考.

The resistance of blended cement paste to sulfuric acid attack was investigated.Two groups of mixtures were tested,cement with slag only,cement with both slag and silica fume.Mass loss,acid consumption and corrosion depth were measured to analyze the deterioration of blended cement paste in sulfuric acid solution.The results show that the porous corroded layer acts as a protective barrier against the direct contact of the inner cement paste with the acid solution.Kinetic equations of sulfuric acid attack were established in form of d=Ktn,where d is corrosion depth,t is corrosion time,K and n are fitting coefficients,to predict their corrosion depth at a specific age.It provides a reference for construction design,maintenance and protection.