Research and Application of Upward Top Coal Caving Mining Technology in Thick Seam

The paper discovered the feasibility of the upward mining technology to the top coal caving mining condition in thick seam for the mine sustainable development.According to the geological conditions of the No.4 mining block in No.3 Jining Coal Mine,with the numerical calculation,theoretical analysis,site measured statistical analysis and industrial trial,the paper had a research on the development features of the failed sub-zone in the strata above the goaf and discussed the feasibility of the upward mining technology under the top coal caving conditions.The paper fully analyzed and solved the upward mining problem under the top coal caving in the thick seam of No.3 Jining Coal Mine.The research results showed that the height of the falling zone from the theoretical calculation and the site measurement ware basically the same and were 14.5～19.15 m and 18.6～21.7 m individually.The numerical simulation analysis showed that the fissure zone at the No.3B seam was within the fissure zone after the coal mining operation of the No.3 seam and the continuity of the seam was well kept.