厚松散层浅埋煤层覆岩破断判据及跨距计算

Criterion of broken and limit stride calculation in shallow coal seam coved with thick loose layer

在分析组合关键层有关参数的基础上,推导出了组合关键层初次来压步距和周期来压步距的计算公式。由于关键层理论和组合关键层理论的载荷和弹性模量不同,而且两者来压步距的计算公式也不相同,因此以关键层理论计算浅埋煤层矿压参数必然会出现很大的误差。大柳塔 1203 工作面按照关键层计算得出的顶板来压步距与实际相差很大,而按照组合关键层计算得出的顶板来压步距与实际基本吻合。以组合关键层理论计算的矿压有关参数与实测一致,这证明对于地表厚松散层浅埋煤层,应采用组合关键层理论。

Combinatorial key stratum is the development of key stratum in shallow coal seam, it has the all properties of key stratum and itself ’s property. Based on the analyzing of parameter about combinatorial key stratum, the formulae of calculating the roof weighting step is given in this article. Because the loader and the moduls of elasticity exists part difference in key stratum and combinatorial key stratum, and the formulae of calculating the roof weighting step has difference, So there must be existing big error if we use the formulae of key stratum to calculate the shallow coal seam’s weighting parameter . According to key stratum theory the 1203 face in Daliuta mining coal roof weighting step has big difference between the observation value and the real value , but according to combinatorial key stratum the face’s roof weighting step consist with the observation value .The consistency proved the formulae of combinatorial key stratum is Correct, shallow coal seam covered with thick loose layer should use the theory of combinatorial key stratum is proved.