Khan Sadaqat Ullah, Nuruddin Muhammad Fadhil, Ayub Tehmina, Shafiq Nasir
Civil Engineering Department, Universiti Teknologi PETRONAS, Block 13, Level III, 31750 Tronoh, Perak, Malaysia.
ScientificWorldJournal. 2014 Feb 18;2014:986567. doi: 10.1155/2014/986567. eCollection 2014.
This paper presents a review of the properties of fresh concrete including workability, heat of hydration, setting time, bleeding, and reactivity by using mineral admixtures fly ash (FA), silica fume (SF), ground granulated blast furnace slag (GGBS), metakaolin (MK), and rice husk ash (RHA). Comparison of normal and high-strength concrete in which cement has been partially supplemented by mineral admixture has been considered. It has been concluded that mineral admixtures may be categorized into two groups: chemically active mineral admixtures and microfiller mineral admixtures. Chemically active mineral admixtures decrease workability and setting time of concrete but increase the heat of hydration and reactivity. On the other hand, microfiller mineral admixtures increase workability and setting time of concrete but decrease the heat of hydration and reactivity. In general, small particle size and higher specific surface area of mineral admixture are favourable to produce highly dense and impermeable concrete; however, they cause low workability and demand more water which may be offset by adding effective superplasticizer.
本文综述了使用矿物掺合料粉煤灰（FA）、硅灰（SF）、磨细粒化高炉矿渣（GGBS）、偏高岭土（MK）和稻壳灰（RHA）时新拌混凝土的性能，包括工作性、水化热、凝结时间、泌水和反应活性。文中考虑了用矿物掺合料部分替代水泥的普通混凝土和高强度混凝土的对比情况。得出的结论是，矿物掺合料可分为两类：化学活性矿物掺合料和微填料矿物掺合料。化学活性矿物掺合料会降低混凝土的工作性和凝结时间，但会提高水化热和反应活性。另一方面，微填料矿物掺合料会提高混凝土的工作性和凝结时间，但会降低水化热和反应活性。一般来说，矿物掺合料的小粒径和较高比表面积有利于制备高密度和不透水的混凝土；然而，它们会导致工作性较低且需要更多的水，这可以通过添加有效的高效减水剂来抵消。
