Study On The Height Of Water Flowing Fractured Zone And Prediction Method In Fully Mechanized Sub-Level Caving

Firstly, based on the fracture and elastic-plastic mechanics, combining the underground pressure theory with the special mining theory closely, establishing every kind of mechanical model on the process of overburden rock failure and analyzing each of them respectively, analyzing dynamic mechanism about the height of water flowing fractured zone in boundary higher than the middle, the paper finds out the overburden rock condition when the highest point of its water fractured zone lies inside or outside the goaf after mining. Then aiming at the conditions of fully mechanized sub-level caving face and based on the analysis and study of the data in situ., it finds out the affecting factors and changing characters to the development of the water flowing fractured zone.Furthermore, summarizing and analyzing the study achievements of finite element simulation, using field example to retrieval the criterion of the scope of water flowing fractured zone, making use of the excellence of ANSYS finite element software and its joint element, studying the effect of different combinations of the overburden, fault and geometry factors on the height and scope of water flowing fractured zone in fully mechanized sub-level caving, the paper gains the basic development laws of water flowing fractured zone under the condition by applying two-dimensional and three-dimensional models.Lastly, combining data in situ., numerical simulation and theory study conclusion, analyzing the main affecting factors of it, considering the mining height, overburden characters and geometry parameters of working face, the paper elicits the new method and formula which can be used to predict the height of water flowing fractured zone in fully mechanized sub-level caving. The error of this formula is very small. The study results of this paper whether to the theory study of overburden failure mechanism or to the engineering practice have important significance and expanding and applying values.