大掺量粉煤灰基多组分矿物掺合料的制备

为获得性能优良的混凝土矿物掺合料，采用正交试验法研究了一种新型的粉煤灰基多组分矿物掺合料，不添加强度激发剂，将粉煤灰、矿渣与天然矿物微粉进行配比优化和复合，产生超叠加效应，通过掺合料各组分之间的复合效应和粉磨效应，起到优势互补和更好的颗粒级配作用，从而获得性能叠加和成本降低的双重效果，试验结果表明：当粉煤灰基复合掺合料在水泥中的掺量为50％（质量分数）时，7d活性指数达56．26％，28d活性指数达76．6％，多元胶凝粉体的标准稠度需水量降低，而混凝土的坍落度与强度提高。

Preparation of Multi-Component Mineral Admixture with Large Content of Fly Ash

In order to prepare mineral admixture with excellent property for concrete, a new type of multi-component mineral material with large content of fly ash as the substitute was investigated by orthogonal experiments. Without any activator, fly ash, granulated blast furnace slag and some natural mineral powders were mixed and the proportion was optimized, which results in a synergistic effect of the components. Moreover, due to the compounding effect and the grinding effect of different components, reasonable particle size distribution and better dense packing effect were obtained, resulting in a good combination of all the different components, thus improving the performance of the mineral admixture and reducing the cost. Experimental results show that, when the content of the fly ash-based admixture is 50% (mass fraction) in cement, the 7-day and 28-day activity indexes respectively achieve 56. 26% and 76. 6% , and that the water consumption for the standard consistence of the multi-component cementitious powder decreases, while the slump and strength of concrete increase.