Study of the Effect of Mining with Transition from Open-Pit to Underground and without Protective Coal Pillar on Slope Stability

As this mining area has a shallow coal seam and a dump, therefore, the mining for the deep resources uses the method of transition from open-pit to underground without protective coal column. In this paper, the numerical simulation method is used to analysis the surface subsidence and slope stability from the two different mining schemes which are from inside to outside, and from outside to inside, in order to obtain the optimization of mining scheme. And settlement and slope stability of rock body are further analyzed from two aspects of fully exploit from the tendency and from toward, the result of an overall slip slope failure caused by underground mining is found. So that in the process of exploitation, corresponding prevention and control measures to the slope safety has been put forward, ensuring smooth production.