摘要
Ⅰ级粉煤灰已成为低标号高性能大坝混凝土的一种不可或缺的掺合料 ,粉煤灰的需水量比是其品质特征的一项重要指标。主要介绍Ⅰ级粉煤灰的需水量比与混凝土单位用水量的关系及其掺量对混凝土用水量的影响。粉煤灰的减水率一般为 10 % ,也可高达 2 0 % ,相当于高效减水剂的减水效果。分析了细度、烧失量、颗粒分布等影响Ⅰ级粉煤灰需水量比的因素。粉煤灰的需水量比与其Dstroks 径有较好的相关关系 ,即微珠含量越高 ,粉煤灰的需水量比越小。
Grade-Ⅰ fly ash has become an indispensable additive of low-strength and high-performance dam concrete,and its water demand ratio is an important quality index.This paper presents the relationship between the water demand ratio of Grade-Ⅰ fly ash and the water consumption of unit concrete and the effect of the additive amount of Grade-Ⅰ fly ash on the water consumption of unit concrete.The water-reducing rate of fly ash is usually 10% and can be up to 20%,equivalent to that of a high-efficiency water-reducing agent.The effect of fineness,burning loss,grain distribution of Grade-Ⅰ fly ash on its water demand ratio is analysed.The water demand ratio of fly ash is well correlative with its Stoke diameter D\- stake ,that is,the higher the microparticle content,the less the water demand ratio of fly ash is.The water-reducing mechanism of fly ash is also discussed.
出处
《人民长江》
北大核心
2002年第1期40-42,共3页
Yangtze River
关键词
粉煤灰
需水量比
高性能混凝土
颗粒
分布
减水机理
fly ash
water demand ratio
high-performance concrete
grain distribution
water-reducing mechanism
