Study On Catastrophic Evolution Mechanism Of Fault Water Inrush In Development Roadway Under Seepage Stress Coupling

The problem of water inrush is one of the main problems of coal mine safety production,and most of the water inrush accidents are due to fault caused by the fault itself both as a water channel and as a strong water rich fault water inrush water inrush,has high concealment,harmfulness,strengthen the analysis of the the coal mine water inrush,will help to deepen our understanding of the evolution of water rich fault water inrush disaster,and provide scientific basis for water inrush can also determine the characteristics of precursory information.This paper takes Guizhou Shuicheng County mine as the research object,based on the investigation of related data,are analyzed through theoretical analysis and numerical simulation on the evolution of study area water rich fault water inrush disaster prevention and mitigation,and puts forward some suggestions according to the results of the analysis.The main achievements are as follows:(1)There is a weak hydraulic connection between the coal bearing strata and the overlying weak aquifer in the area.Only when the water diversion fault or other water diversion channels communicate with the overlying aquifer to produce hydraulic connection,will it affect the coal mining or tunneling.In the excavation disturbance,roadway before full water fault,most likely caused by water inrush accident.This is because there is no water filling aquifer exists in the stratum,the water rich fault has served as a source of mine water,on the other hand also acts as a water channel role,resulting in this type of water inrush is highly unpredictable and sudden,great harm.(2)The numerical simulation software to simulate the roadway excavation process based on the mined out area and water rich fault fracture zones,regional displacement,stress and seepage field affected,analyzed and summarized the coupling of stress field and displacement field and seepage field evolution of water inrush evolution process,the results of the study show that: strong water rich the water inrush in the excavation disturbance and fault fracture zone water interaction results in this process,the multi field information continuously changes of aquifuge in rock,the totlal partition can be divided into three gradation,the working face is far away from the fault initial phase change driving distance of the working face(?mL 24);that is close to the fault phase of rapid changes in the driving distance(m ??5224mL);the driving distance of the mutation stage(?mL 52).(3)Based on multi physical field coupling simulation software,we simulate the seepage process of water rich fault inrush.Coupled with the Forchherimer non Darcy flow and NavierStokes turbulence nonlinear seepage model,we reproduce the dynamic process of water rich fault water bursting in the development roadway.When the water inrush in the whole basin,groundwater along the fault zone since the downward pressure on the way into the tunnel,the runoff decreased continuously,the overall flow increases,but after entering the water inrush channel and tunnel,due to changes caused by the flow rate decreases,then increases again,eventually entering the tunnel after the velocity and pressure tends to be stable.(4)The validity analysis of prediction of water rich fault water inrush through the internal connection of multi field information changes and found,multi field change information has relatively obvious precursory characteristics in water rich fault water inrush in aquifuge before breaking induced water inrush,the surrounding rock should be increased after the occurrence of the fall;slow growth after the displacement of surrounding rock increases rapidly,and the broken fault zone in vertical to reduce negative displacement of the surrounding rock;pore water pressure increases obviously in the near fault,but appear on the verge of water inrush decreases;the flow direction on the brink of the water inrush channel when water inrush flow changed obviously.(5)Based on the strength theory,the coal mine safety regulations and the numerical simulation results,the thickness of the anti septate layer is taken into consideration.The thickness of the regional critical anti septum layer is 1.5-4.5m.Based on the analysis of the water inrush disaster in the development roadway of the coal mine in the coal mine,based on the premise of reserving a certain thickness of the water proof layer,and aiming at the actual situation of the mining area,some suggestions for strengthening the personnel education and monitoring are put forward.