A Study on the Development and Evolution of Fractures in the Coal Pillar Dams of Underground Reservoirs in Coal Mines and Their Optimum Size

The western mining areas of China, which are rich in coal resources, lack water resources. Large-scale and high-intensity China’s has led to the loss groundwater Underground reservoirs mines an effective means achieving protection utilization resources these areas. One important standards for safety underground reservoir a mine involves checking whether development cracks pillar dam body, under dual stress conditions overlying strata lateral pressure, passes through body or its top bottom plates, forming seepage channel water. This article focuses on issues associated with dams mines. From perspectives rock pressure dams, mechanical models, numerical calculations, similar simulation methods were used analyze macroscopic deformation, displacement, crack different sizes vertical horizontal study optimum width dams. Our research results indicated that optimal can be determined via based deformation state given dam. When increases, smaller is, greater increment syy sxx becomes, more likely is damaged. Similar simulations showed size easier it generate concentration, this “eat away” body. There certain relationship between range development. larger less obvious concentration effect penetrate internal external parts reservoir. Taking Shangwan as example, was maximum head height could carried by 15-m 50 m. A comprehensive evolution mine, characteristics sliding instability, conducted determine storage does not inner outer factors affecting stability expand improve basic theory mines, provide scientific basis determining dam, guarantee long-term safe stable operation continuously save increase economic benefits These implications great significance geological conditions.