利用钼尾矿制备活性粉末混凝土的研究

Study on the preparation of reactive powder concrete with molybdenum tailings

采用钼尾矿砂部分取代石英砂,钼尾矿粉部分取代硅灰制备活性粉末混凝土(RPC),研究钼尾矿砂、钼尾矿粉对RPC工作性能和抗压强度的影响,确定钼尾矿砂、钼尾矿粉的最佳掺量。结果表明,在水胶比和砂胶比一定时,以钼尾矿部分取代石英砂或硅灰,会使RPC的流动度下降。钼尾矿砂部分取代石英砂,RPC的抗压强度随钼尾矿砂掺量的增加先提高后降低;当钼尾矿砂掺量为20%时,RPC常温标准养护28 d抗压强度为157.16 MPa。以钼尾矿粉部分取代硅灰,随钼尾矿粉掺量的增加,RPC的抗压强度早期增长速度较快,后期增长较慢;当钼尾矿粉掺量大于40%时,大部分钼尾矿粉作为细集料起填充作用,不利于强度的产生。

The activated powder concrete(RPC)was prepared by using molybdenum tailing sand/powder instead of quartz sand or silica fume.The effects of molybdenum tailing sand/powder on the working performance and compressive strength of RPC were studied respectively.The optimum content of molybdenum tailing ore/powder was determined.The results showed that when the wa-ter-binder ratio and sand-binder ratio were constant,the fluidity of RRC was reduced when quartz sand or silica fume was partially replaced by molybdenum tailings.Molybdenum tailing sand partially replaced quartz sand,and the compressive strength of RPC showed a trend of increasing first and then decreasing.When the content of RPC was 20%,the compressive strength of RPC was 157.16 MPa after standard curing at room temperature for 28 days.In the early hydration process,the strength of molybdenum tailing powder partially replacing silica fume increased rapidly in the early stage and slowly in the later stage.When the content of molybdenum tailing powder was more than 40%,most of molybdenum tailing powder played a filling role as fine aggregate,which was not conducive to strength generation.