Determination of the Height of Water Flowing Fractured Zone in Overburden Strata Above Fully-Mechanized Top-Coal Caving Face

In order to determine the height of water flowing fractured zone in overburden strata above fully-mechanized top-coal caving face,the mechanics model is established to provide the design basis for the coal mining according to the mechanical parameters of rocks and the exploitation technical conditions in a certain fully-mechanized top-coal caving face.By using the rock failure process analysis software(RFPA~(2D)),the deformation and falling of the overburden strata are simulated to determine the height of water flowing fractured zone in overburden strata as the coalface advanced.And the height of water flowing fractured zone in overburden strata is calculated by the empirical formula and is measured with a simple hydrological observation method according to drilling on spot.Compared with three results mentioned above,the numerical simulation result nearly the same as that on spot,and the result from the empirical formula is conservative and safe in practice.So it is efficient for numerical simulation to determine the height of water flowing fractured zone in overburden strata.