低品质粉煤灰在混凝土中的应用

Utilization of low-quality fly ash in concrete

国标将粉煤灰划分为三个等级,其中I、II级粉煤灰在混凝土中已得到广泛应用,而III级及等外灰,即低品质粉煤灰,由于其颗粒粗、含碳量大、活性低等缺点使其在混凝土中的应用受到限制。对粉煤灰的碱性、硫酸盐和氯盐改性的机理作了分析,并简要论述了目前低品质粉煤灰在混凝土中的主要应用形式:作为掺合料和细骨料等。为低品质粉煤灰在混凝土中的应用提供借鉴。

Fly ash is divided into three levels in Chinese National Standard.The fly ash of I and II level has been widely applied in concrete.But, there are some limitations in the application of fly ash of IlI level and level outside the National Standard,both with low quality,in concrete because this kind of fly ash has coarse particles, large carbon content and low activity.Briefly analyzes the mechanism of modification of alkaline, sulphate and chloride and exhibits the main applications of fly ash with low quality in concrete：replacing cement and replacing fine aggregates, etc.Provide reference for the applications of fly ash with low quality in concrete.