地表厚松散层浅埋煤层组合关键层的稳定性分析

Analysis of combinatorial key strata stability in shallow coal seam with thick loose bed

把关键层理论应用于地表厚松散层浅埋煤层 ,并利用推导出的组合关键层岩柱回转接触面尺寸 ,分析其滑落失稳和回转失稳的关系即“R -S”稳定性 ,给出了组合关键层岩柱不同断裂度的最大回转角 .得出地表厚松散层浅埋煤层顶板管理的主要问题是组合关键层岩柱的滑落失稳 ,即覆岩全厚度沿煤壁的台阶切落 ;讨论了地表松散层厚度对组合关键层岩柱稳定性的作用 .

The key stratum theory is applied in shallow seam with thick loose bed, and the relationship between instability due to sliding and rotational distortion instability i e. “S-R' stability is analyzed by concluded contact dimension of rock column formed by broken combinatorial key strata. The maximal rotational angle for different ratio of thickness to length of rock column is given. The conclusion that the key problem of roof control for shallow seam with thick loose bed is sliding instability of combinatorial key strata i.e. overlying strata fall out and sink intact along coal wall is drawn. The influence of loose bed thickness on stability of combinatorial key strata is discussed.