Failure Characteristics of Fault Structure under Mining Effect and Evaluation on Water-inrush Risk

Author:Yuan Jiu Dang

Supervisor:zhang wen quan zhang pei sen


Degree Year:2018





With the continuous improvement of energy demand in China,the mining depth of coal mine is increasing,and the accident rate of coal mine is increasing.Mine water inrush has become a problem to be solved urgently in the background of large mining depth.In our country,the hydrogeological conditions of coal mine are complex,and the coal mining process is threatened by a variety of water bodies.Only about 1.5 billion tons of coal reserves are threatened by karst water in the main mining areas in the north,and only 88.1%of the water damage in the water disaster in China is caused by the floor water damage.Therefore,it is correct to know and analyze the fracture characteristics and the water inrush of the floor in the process of mining.It is not only related to the production safety and economic benefits of the mine,it’s also to the recovery of coal resources,the protection of the water resources of the mining area and the sustainable development of the coal industry.In this paper,the research on the characteristics of fracture structure and the risk assessment of water inrush under the mining effect is carried out,and the relevant research work is carried out in depth,and the main achievements are as follows:1)On the basis of analyzing and summarizing the characteristics of deep fracture structure failure,the existence characteristics of karst water in the mine floor and the mechanical properties of the floor rock mass,the theoretical analysis method is adopted to analyze the mechanical characteristics of fracture structure and the damage state of the floor rock mass under the mining effect;2)Using the JAW-600 numerical control rock jointing shear seepage test system and the MTS815.03 electro-hydraulic servo rock test system,the fractured rock mass and deep rock sample are tested and analyzed,and the seepage law of the fractured structural rock mass under different working conditions is obtained;3)With the aid of similar material simulation test system,the conductivity of the bearing pressure water in the fault zone of the complete floor structure,the law of movement and failure of the overlying strata on the working face,and the spatial distribution and development characteristics of the floor fissure in the process of mining face with hidden fault structure development face are discussed,and the formation of water inrush from the floor is reproduced.The process of catastrophic evolution of water inrush section,water bursting section and burst water burst section in the process reveals the water inrush mechanism of deep mining fracture structure extending from damage to abrupt fracture;4)Using the numerical simulation method,the stress and displacement distribution characteristics of the coal seam floor,the fracture structure failure characteristics and the seepage field characteristics under the mining effect,the deformation and failure evolution law of the deep mining face plate along with the working face,and the deformation and failure characteristics of the bottom plate under different working conditions are discussed,and the failure of the bottom plate is revealed.The mechanism provides a scientific basis for deep mining;5)Using the analytic hierarchy process(AHP)and Fisher classical discriminant analysis theory,the water inrush subarea of coal mine floor based on GIS technology is determined,and the prediction of water inrush is carried out on the rock floor with fracture structure.