以榆神矿区小保当井田2-2煤层覆岩为地质原型,基于区域地质条件和3个代表性钻孔构建了30个不同岩土比类型的数值模型,运用数值模拟试验的方法研究在地质条件和开采工艺相同的情况下,覆岩岩土比对开采沉陷的影响规律。研究结果表明:在250m和300m埋深水平下,下沉系数都会随着岩土比的增大而减小;在350m埋深水平下,下沉系数整体上呈现随岩土比增大而变小的趋势(岩土比为2∶1的点除外)。针对3种不同埋深水平建立了岩土比与下沉系数的量化关系;在不同的埋深水平下,岩土比对下沉系数的影响程度不同,随着埋深的增加,下沉系数的减小幅度基本表现为先变大后变小。
Taking the overlying strata of 2^-2 coal seam in Xiaobaodang mine field in Yushen mining area as geological model, 30 numerical models with different rock-soil ratio were structured on the basis of regional geological conditions and 3 typical drillings. With the method of nu- merical simulation, the effect law of the rock-soil ratio on the mining subsidence was researched under the same geological condition and mining technology. The results showed that the subsidence coefficient would decrease with the increase of the rock-soil ratio at the buried depth of 250 m and 300 m; at the buried depth of 350 m, the subsidence coefficient decreased with the increase of rock-soil ratio as a whole except that the rock-soil ratio was 2 : 1. The quantitative relation between the subsidence coefficient and the rock-soil ratio was built under three different depth levels. Under the different depth levels, the degree of the effect of the rock-soil ratio on the subsidence coefficient was different, and with the increase of buried depth, the decrease extent of the subsidence coefficient got bigger before it got smaller.