综采充填黄土侧限压缩特性试验

为了揭示综合机械化充填开采黄土压缩特性,对22种黄土试样采用液塑限联合测定法测得了界限含水率,得出充填黄土与石灰的比例关系及最佳含水率;通过侧限压缩试验测得充填黄土压缩过程中应力应变关系曲线和密度应力关系曲线,确定了充填压实机构的夯实力以及煤矿充填开采过程中煤炭开采量和黄土充填量的采充比.研究结果表明,在黄土充填开采过程中,需掺入7%的石灰以改良黄土的特性,且最优含水率不宜超过17%,充填入采空区后的黄土需进行不小于2MPa的初步压实,采充比达到1.41才能保证充填效果.

Experimental study on confined compression of loess in backfilled fully mechanized coal mining

To investigate the compression characteristics of filling loess in fully mechanized coal mining with backfill,the experimental loess samples of 22 types are tested in this study.Through the combined determination method of liquid and plastic limits of loess,the best moisture content and best sample are obtained.With the confined compression tests on loess,the stress-strain curve and the density-stress curve are drawn.Based on these curves,the pressure strength of rammer compactor,and the ratio of mined coal and backfilled loess are determined.The results show that the loess should be mixed with 7% of lime for improving the characteristics of loess,and should be added an optimum portion of water not more than 17%.The optimal ratio for the amount of the backfilled loess and the mined coal is 1.41.The loess should be compressed with the initial pressure not less than 2MPa.