尾矿砂喷射钢纤维混凝土弯曲韧性研究

THE RESEARCH ON FLEXURAL TOUGHNESS OF TAILING SAND STEEL FIBER SHOTCRETE

以尾矿砂取代天然砂配制的尾矿砂喷射钢纤维混凝土,并参照美国材料与试验协会(ASTM)试验方法,借助弯曲荷载-挠度曲线,分析粉煤灰掺量、硅粉掺量和钢纤维掺量对混凝土弯曲韧性影响。结果表明:粉煤灰降低尾矿砂喷射钢纤维混凝土峰值荷载和峰值位移。而钢纤维对峰值荷载影响较小,对变形性能影响较大,同时,增大硅粉掺量仅能提高混凝土的峰值荷载。另外,发现尾矿砂喷射钢纤维混凝土的最优粉煤灰掺量和钢纤维掺量为20%和40%。

The paper takes tailing sand to replace natural sand to make up tailing sand steel fiber shotcrete （TSSC）. According to the testing method of ASTM, and through the load - deflection curves of TSSC, the effects of the content of fly ash, silica fume and steel fiber on flexural toughness were researched. Research results show that： fly ash can decrease the peak load and peak deflection of TSSC. The steel fiber has little effect on peak load, but it has good effect on deformation performance. At the same time, increase the content of silica fume can only increase peak load. In addition, the best content of fly ash and silica fume are 20% and 40%.