某铅锌矿全尾砂胶结充填体强度试验研究

Experimental Study on Strength of Full Tailings Cemented Backfill of a Lead-zinc Mine

以某铅锌矿全尾砂为充填骨料、水泥为胶凝剂制作胶结充填体,测定了全尾砂物理化学特性,并用三因素四水平正交试验设计进行单轴抗压强度试验,研究了全尾砂胶结充填体抗压强度与灰砂比、质量浓度和养护时间的敏感性,通过对各因素的多元线性回归分析推荐了充填料浆最优配比。结果表明:当全尾砂不均匀系数大于5时,可用作充填骨料且制成的充填体密实程度好;胶结充填体抗压强度与灰砂比、质量浓度及养护时间成正比;灰砂比对充填体抗压强度的影响最敏感,养护时间次之,质量浓度最小;推荐该矿最优充填配比方案为灰砂比1∶4、质量浓度76%、养护时间28d。

The cemented filling body was prepared by using the full tailings of a lead-zinc mine as the filling aggregate and cement as the gelling agent.The physical and chemical properties of the full tailings were tested,and the three-factor four-level orthogonal test was designed to carry out a uniaxial compressive strength test.In addition,the sensitivity of the compressive strength of the full tailings cemented filling body to the lime-sand ratio,mass concentration and curing time was also studied,and the optimal ratio of filling slurry was recommended by multiple linear regression analysis of various factors.The results exhibit that when the non-uniformity coefficient of the whole tailings is larger than 5,it can be used as filling aggregate and the filling body made is dense;Besides,the compressive strength of cemented filling body is proportional to the lime-sand ratio,mass concentration and curing time.Furthermore,the sensitivity of limesand ratio,curing time and mass concentration to the compressive strength of the filling body from high to low is:lime-sand ratio>curing time>mass concentration.It is recommended that the optimal filling ratio of the mine is a lime-sand ratio of 1∶4,a mass concentration of 76%,and a curing time of 28 d.