基于关键层理论的地表下沉盆地模型初探

Preliminary study of surface subsidence model based on theory of key rock stratum

目前,开采沉陷的研究主要是现场观测和以概率积分法为代表的开采沉陷预测。这些方法仅是对地表沉陷稳定后的现象进行观测和推断,不涉及对采场上覆岩层整体移动规律的研究。因长壁式布置工作面开采煤层的深厚比较大时,采场上覆岩层在靠近地表处会形成明显的弯曲带。在假设此弯曲带是控制地表沉陷及沉陷盆地最终形态的离地表最近一层主关键层且地表的下沉量远远小于该岩层厚度的基础上,用关键层位置的判别方法找出离地表最近一层关键层的位置后,用弹性薄板理论的半逆解法选择了较适合地表沉陷盆地形状的挠度函数,用薄板理论建立了缓倾斜煤层和倾斜煤层开采地表沉陷盆地力学模型,并对该模型的适用范围和参数进行了讨论。该模型考虑了影响地表下沉的多种因素,比概率积分法更具有理论意义。

The main research way of the surface subsidence due to underground mining is local observation and prediction based on the probability integral at present.These ways for studying surface subsidence is only can observe and infer the phenomenon of the subsidence;it is not study of the law for the movement process of the whole rock up the coal mining room.The rock stratum near by the surface will form a bend band when the ratio of the depth of the embedment and the thickness of the coal seam up long-wall mining coal face is very large.The bend band is one of key rock stratum near surface.Presumed this key rock stratum is controlled the rate and shape of the subsidence basin and the rate is far below the key stratum rock thick.Used the theory of key stratum to estimate the location of the rock stratum near surface and selected the suitable bending function,the surface subsidence basin model is set up by the way to survey the elasticity sheet.Discussed the applicability scope and parameter determine of this model is.This model is taken into consideration much factor of the rock stratum up the mining room,so the ideal for this model is more progress than use the probability integral function to predict the surface subsidence.