Research On The Karst Development Regularity And Water-bearing Mechanism Of The Structuresin Shuozhou Coalmine

Shuozhou coalmine including Yangjian,Dongpo,Danshuigou and Xishahe, near the Danshuigou fault with secondary structure,such as faults, karst collapse columns which were revealed in working face. The floor ordovician limestone aquifer located in the strong karst run-off zone of Shentou spring field, where DP-1 hole pumping test obtained permeability coefficient(K), unit inflow(q) and other parameters are very large. When the 11#coal mine is mined, water inrush coefficient will reach 0.07~0.12MPa/m, ordovician limestone water is extremely likely to water inrush through fault and collapse column. Therefore, it has important theoretical and practical significance to carry out research on karst development regularity and water-bearing mechanism of the structures in Shuozhou mining area.According to the above serious water hazard problems faced in the process of coal mining, this paper focuses on the ordovician limestone karst, collapse column, and structural control of water, combined with drilling, geophysical exploration, field survey and analysis of the geological background, as well as hydrogeological characteristics.Summarized as follows.Firstly, on the basis of statistical analysis of all exposed ordovician limestone drilling in the area, the top of ordovician exist 11m-24 m aquiclude.Secondly, karst development regularity indicate. that vertical development show changes from weak to strong and weak,and it will be divided into three sections of ordovician limestone where 20m-80 m is the first period of weak water section, 80m-240 m is the second water rich section, 240m-400 m is the third weak water section. Thirdly, checking computation of DP-1 pumping main parameters, the permeability coefficient(K) is 295m/d, units inflow(q) is 208.75 L/s·m. Fourthly, analysis and and explaination the causes of karst collapse column in Shuozhou coalmine, roughly divided into the Middle Ordovician limestone sedimentary diagenetic stage, Hercynian and Indosinian karst stagnation stage, Yanshan strongly developed karst with preliminary collapse column. Himalayan collapse column inheritance and development, forming a preliminary understanding of the collapse column water conductivity. Fifthly, regard the preferred plane theory as the foundation, using the grey hierarchical clustering method, qualitative and quantitative distinction between fracture levels of 4 mines, illuminating water-bearing mechanism of the structures. Sixthly, based on the analytic hierarchy process, the unit inflow, aquifer thickness, drilling fluid leakage, the faults and the groundwater level variation of five impact factors for the evaluation of ordovician limestone water, provide a new basis for the prevention and control of mine water.