粉煤灰对矿渣胶结充填材料性能的影响

针对粉煤灰具有来源广、价格低廉和能改善砂浆施工性能的特点，研究了粉煤灰对矿渣胶结充填材料强度和流动性的影响。结果表明：在以石灰和脱硫石膏为激发剂制备的矿渣胶凝材料中，随着粉煤灰添加量的不断增大，充填体的抗压强度逐渐下降，每添加1%的粉煤灰，7 d强度平均降低1.82%，28 d强度平均降低1.61%；但是充填料的屈服应力和塑形黏度却在不断降低，说明粉煤灰的添加能够很好地改善充填料浆的流变性，实现砂浆高浓度自流输送。综合考虑强度和流变性的影响效果，粉煤灰的最优掺量范围为10%~20%。

Influence of Fly Ash Performance of Slag Cemented Backfilling Materials

In view of the features of fly ash as abundant resources，low costs and improving the construction of mortar，the influence of fly ash on strength and liquidity of slag cemented materials is studied through experiments. The results show that the slag cemented backfilling materials with the lime and desulfurization gypsum as the activator，the compressive strength of backfilling body gradually declined with the adding amount of fly ash increasing. 1% of fly ash is added each time，the intensity decreased by 1.82% at 7 d and by 1.61% at 28 d on average. Meanwhile，the yield stress and viscosity of the backfilling is getting lower，which indicates that fly ash can largely improve the rheology of backfilling materials，and make high concentration of mortars conveying by gravity flow. Comprehensively considering the strength and the rheology，the optimal dosage of the fly ash ranges from 10% to 20%.