Deformation control of high and steep mountain under condition of multi-coal mining

The prevention and control of massive high-speed and long-distance landslide induced by underground mining will run through the whole stage of planning,development and mine closure in Southwest China. The stability control of mining slope is very important in the early planning stage. In order to improve the level of disaster prevention and reduction in mining areas,based on geology and mining conditions,the disaster factors of controlling the stability of high steep mountains are summarized systematically,a multi seam coordinated mining method suitable for the stability control of high and steep mountains in the mining area is put forward,and the discrete element method to simulate and analyze the deformation characteristics and stability control effect of mountains is used. The results show that underground mining is the main cause of slope deformation,and the superposition of gravity field and mining stress field causes stress concentration,which is the essence of rock fracture and slope instability. Coordinated mining of multiple coal seams can reduce the deformation and failure rate of overburden,gradually release the total deformation,dynamically adjust the sensitive indexes of slope stability,such as horizontal deformation and slope stability,and improve the stability of mining slope. By using this method,the maximum horizontal deformation are reduced by 67%-85%,the maximum inclination are reduced by 41%-67% respectively,and the stability of tiziya (limestone of Yongning formation) is controlled. Multi seam coordinated mining technology is an effective way to solve the problem of safe and efficient mining of coal resources under the high and steep mountain in Southwest China.