关键词: 碱集料反应;硅粉;膨胀率

Abstract: Through the investigation and analysis of the aggregate in Qinghai area, it was found that the aggregate in Qinghai has high alkali activity.The typical sand aggregate which from the north of Xining city was used, and the aggregate of Datong area was studied.The comparative analysis of the inhibitory effects of different dosage of silica fume on alkali aggregate reaction.The results show that: for the two low activity north of the city of stone, stone aggregate Datong, when choose the content of 10％ or 15％ or 20％ silica fume, expansion rate is less than 0.1％ in the next 14 d, the expansion could effectively inhibit AAR.And for the north sand high activity of aggregates, when choose the admixture of 20％ silica fume, the expansion rate of 14 d is less than 0.1％, can effectively inhibit AAR expansion.

Key words: alkali aggregate reaction;silica fume;expansion rate