Mining Scheme Optimization And Filling Technical Research Of The Large And Thick Ore Body In The Yongping Copper Mine

Abstract:The transition to underground mining from open-pit in the Yongping copper mine leads to the deficiency of the underground production technique and managerial experience. To guarantee the regular production, systematic research was needed for the safe and efficient mining and filling process of the large and thick ore body. The production technique of large and thick ore body in the Yongping copper mine was intensively investigated by theoretical analyses, laboratory tests and numerical simulations in the dissertation. The primary research works and conclusions were summarized as follows:(1) Combined with the mining technical conditions, two new schemes were proposed based on the original scheme. Fuzzy mathematical method was then introduced to quantitatively evaluate the three schemes. The middle-deep hole room and pillar afterwards filling mining method with ore removal from the bottom of the original rock was selected as the optimal scheme, which locates the bottom structure of both the room and pillar at the original rock to guarantee the safety of the two-step extraction, and to achieve large production capacity, great mining efficiency, high recovery rate and low production cost.(2) Stability analyses of the chamber and pillar extraction were conducted for both the original and optimized scheme by the numerical simulation. By comparison, the stress, displacement and plastic deformation zone of the optimized scheme decrease notably, which guarantees the safety of the two-step extraction and verifies the feasibility of the optimized scheme.(3) Combined with the laboratory experiment, a comprehensive analysis was carried out on the physico-chemical properties of the filling materials and the strength of cemented filling body with different proportions. The corresponding physico-chemical properties and strength of cemented filling body under different conditions were obtained, and the economic and reasonable filling ratio was recommended.(4) Combined with the experience at home and abroad, the filling retaining walls, the dehydration and filtration of water were investigated. The reasonable type and parameters of retaining walls were determined, the dewatering and drainage facilities meeting the practical working environment were designed, a feasible scheme of the filling process was optimized...