大掺量混合材高性能混凝土的制备及强度特性

在固定用水量为130 kg/m3下,研究了粉煤灰、磨细矿渣和硅灰对水泥替代量为30%、50%、70%,水胶比为0.33的高性能混凝土的制备。探讨了粉煤灰、硅灰和矿渣对新拌混凝土流动性和抗压强度的影响。在低水胶比情况下,粉煤灰、磨细矿渣和硅灰大掺量复掺,可制备得到工作性良好、早期强度满足要求和后期强度有极好发展的高性能混凝土;在高效减水剂的作用下,在大掺量混合材混凝土中以硅灰、磨细矿渣取代部分粉煤灰,可以有效提高大掺量混凝土的早期强度,进一步改善新拌混凝土的工作性。

Preparation and Strength Property of High Performance Concrete with High Volume Mineral Admixture

The preparation of high-performance concrete with the replacement of fly ash,granulated blast furnace slag,and silica fume alternative to the weight of cement(30%,50%,and 70%),water-binder ratio of 0.33 was studied under the condition of water consumption of 130 kg/m3.The influence of fly ash,silica fume and granulated blast-furnace slag on the fresh concrete workability and compressive strength was also discussed.The results show that high-performance concrete,which have good workability,early strength and excellent development of final strength can be obtained when with low water-binder ratio,large amount of fly ash,granulated blast-furnace slag and silica fume replacement.Replacing silica fume,granulated blast-furnace slag to a portion of fly ash,with superplasticizer,in high volume admixture of concrete,can further improve the workability of fresh concrete and effectively raise the early strength.