矸石基新型固体充填材料配比优化试验研究

Experimental study on proportion optimization of gangue-based new solid filling materials

为了研发新型固体充填材料,降低充填采煤成本,提高充填开采效率,对以矸石为基础的单一材料、2种及2种以上的混合材料压实特性进行了研究;通过实验室试验、理论计算等研究方法对材料的宏观变形情况进行了分析,并采用SEM、XRD等技术手段对材料的微观结构和物相组成进行了表征。矸石粒径级配优化试验中,分析了最大粒径和级配系数对压实变形的交互影响,得出最佳级配组合为粒径D=30 mm,级配数n=0.3。矸石-河沙压实变形特性试验中,采用河沙对细矸进行替换,进一步提高了充填骨料的抗变形能力。固体混合材料试验中,基于正交重复试验原理中的极差和方差分析,得出最佳矸石用量为65%,最佳土灰比为2∶3,矸石用量对试验结果的影响高度显著。综上,确定了新型固体充填材料的配比为矸石:黄土:粉煤灰=65%∶14%∶21%,此种情况下充填材料承压能力最强,充填开采成本最低。

In order to develop new solid backfill materials,reduce the cost of backfill mining and improve the efficiency of backfill mining,the compaction characteristics of single material and two or more mixed materials based on gangue were studied in this paper.The macroscopic deformation of the material was analyzed by means of laboratory tests and theoretical calculations,the mi-crostructure and phase composition were characterized by SEM and XRD.In the experiment of gangue particle size gradation opti-mization,the interaction of maximum particle size and gradation coefficient on compaction deformation was analyzed,and the opti-mal gradation combination is particle size D=30 mm,grading coefficient n=0.3.In the test of gangue-river sand compaction defor-mation characteristics,river sand was used to replace the fine gangue,which further improved the anti-deformation ability of the filling aggregate.In the test of solid mixed materials,based on the range and variance analysis in the principle of orthogonal re-peated test,the optimal dosage of gangue was 65%,the optimal soil-cement ratio was 2∶3,and the influence of the dosage of gangue on the test results was highly significant.In conclusion,it was determined that the ratio of new solid filling materials was gangue:loess:fly ash=65%∶14%∶21%.In this case,the filling material had the strongest bearing capacity and the lowest filling mining cost.