花岗岩石粉特性及其掺合料性能研究

Study on the characteristics of granite rock powder and its admixture properties

为了验证不同类型花岗岩石粉作为矿物掺合料在胶砂或混凝土中的适用性,推进石粉应用,采用3个地区的花岗岩石粉作为掺合料,研究单掺以及复掺粉煤灰、矿粉、硅灰对胶砂流动性能及强度活性指数的影响。结果显示:单掺甘肃地区花岗岩石粉的胶砂流动性较差,但其活性指数高于单掺广东和四川地区花岗岩石粉的,单掺各花岗岩石粉胶砂流动度比均小于100%,强度活性指数总体在65%,说明花岗岩石粉是一种惰性材料,其掺入对胶砂的流动性和力学性能会产生不利影响;但将花岗岩石粉分别复掺粉煤灰、矿粉、硅灰后,流动性和抗压强度均有一定程度的改善,且3种复掺体系胶砂的7 d强度均高于基准组,说明矿物掺合料对于提高胶砂早期强度有一定的促进作用。

In order to verify the applicability of different types of granite powder as mineral admixtures in mortar or concrete,and promote the application of stone powder,granite stone powder from three regions was used as admixtures to study the influence of single and compound admixtures of fly ash,mineral powder and silica ash on the flow performance and strength activity index of mortar.The results show that the flowability of granite powder in Gansu region is poor,but the activity index is higher than that in Guangdong and Sichuan regions.The flowability ratio of granite powder in all three regions is less than 100%,and the overall strength activity index is 65%.This indicates that granite powder is an inert material,and its incorporation will have adverse effects on the flowability and mechanical properties of the mortar;However,when granite stone powder is mixed with fly ash,mineral powder,or silica fume separately,its flowability and compressive strength are improved to a certain extent,and the 7-day strength of the three mixed systems of mortar is higher than the benchmark group,indicating that mineral admixtures have a certain promoting effect on improving the early strength of the mortar.