Study On The Prediction Method Of Water-flowing Fractured Zone's Height And Its Application

Movement and failure of underground-induced strata can make surface and underground water in mining scope inrush coal mine and bring enormous harm to frail ecological environment in western area. Considering the precondition that coal mining in western area must protect good water resources, the developing height to grasp the movement and failure of overburden strata and the relationship between water-flowing fractured zone and overlying water are researched. Thus, determining reasonable safe mining upper limit and mining method for mining safety, water-preserved coal mining and ecological environment protection, have extremely important theory significance and practical value.By means of RFPA, the failure process and water flowing ability of rock are simulated under uniaxial tension stress. Failure types of stratas in coal seam and their judgment method are founded out. Concrete mining model is built by FLAC and load transfer mechanism, effect of load control strata and its calculating method above key strata are put forward. According to these theory study conclusion, attaching the on-the-spot data, taking the fracture and elastic-plastic mechanics knowledge as the foundation and the key strata theory as the instruction and considering overburden character, mining height, parameters of working face and crack-expansion characteristics of caving rock, a new method from the mechanism angle by studying on failure conditions of underground-induced strata and judgment method of water-flowing fractured zone's height is elicited. Example examination shows the result forecasted through the method and the measured result are basically tally and the error is very small. Finally, the achievement is applied in Shendong mining area to study the failure law of underground-induced strata and the characteristics of water-flowing fractured zone for making scientific policy-making basis to realize mining safety, environment protection and underground water protection. The study results of this dissertation have important significance and expanding applied values on the theory study of overburden failure mechanism and the engineering practice.