Simulation Research And Actual Measurements On Water Conservation Mining And Overlayer Strata Movement Of Thick Base Rock Shallow Seam

Yushenfu Mining Area is the biggest modern energy base in China. Shallow buried depth and overlying thick unconsolidated formation layers are the typical occurrence characteristics of this mining area. Mining face diving easily causes the loss of the surface phreatic water, which damages ecological environment. Green mining is the future development ( orientation ) of mining technology and water-preserved-mining is an important aspect of that. To carry out research and practice on water-preserved-mining of shallow seam has an important academic value and social significance.The paper is based on the background of geological conditions of Yushuwan mine,in Yushenfu Mining Area, relys on the National Natural Science Foundation Project"Study on the Character of Surface Aquiclude in Shallow Seam"and horizontal project"Study on water conservation mining and stress behavior of yushuwan coal mine", develops the technology of stress-strain complete resemble simulation of aquifuge by the method of combining physics resemble simulation with theoretical analysis, grasps the basic law of water preserved mining of overlying strata movement in shallow seam in Yushuwan mine, and analyzes the stability of aquiclude and feasibility of water conservation mining. According to water-preserved-mining's practice and measurement, the basic law of working face strata behaviors is mastered and the correctness of the experimental study is proved.Through systematical analysis of mining area's geological conditions systemly, the paper tests aquiclude's physical and mechanical properties and obtains stress-strain complete curves of aquiclude rock sample. Based on properties of aquiclude, it analyzes that the key of aquiclude simulation is to realize stress-strain complete resemblance, in particular plastic deformation resemblance, hereby, proposing aquiclude similar index and conditions and developing similar simulation technology. According to properties of aquiclude, the experiments determine the similar material and ratio law of aquiclude and realize stress-strain complete resemble simulation of clay aquiclude. By taking Yushuwan mine as the research object, the correctness of aquiclude similar material and ratio selection is proved through similar simulation experiments. Through physical simulation, the paper reveals the basic law of water conservation mining of overlying strata movement in shallow seam Yushuwan mine and analyzes"three-band"characteristics of rock movements. The experiments obtain that the key strata of bedrock in shallow seam has a significant effect on the stability of aquiclude and clay as well as loess aquicludes are key stratum of water-preserved-mining. With a 5m mining height, aquiclude(movements) wholly sink curved and its properties are not destroyed. So water-preserved-mining can be achieved.According to simulation experiments, the practice of water conservation mining is carried out in Yushuwan Mining Area. Through measurement the basic law of working face strata behaviors and top roof water spraying are obtained, what's more, the correctness of theoretical analysis and simulation experiments is proved. The paper's reasearch provides experimental methods and practical experience for the research and practice of water-preserved-mining, also reference for similar studies and practice.