Study On Reinforcement Design For Open Pit Slope Under The Underground Mining

There are a large number of and large-scale open pit in our country. Slope stability of open pit is directly related to the production safety and economic development of mining. Into the 21st century, with increasing the size and depth of exploitation, open coal mining faces more difficulty, open pit have access to underground mining phase. As the complexity of geological conditions, together with continuous underground mining, it has not only resulted in lower slope stability, but also seriously hampered the normal mine production and restricted sustainable, healthy and stable development. Therefore, how to ensure the stability of open pit slope under underground mining becomes an increasingly prominent and urgent major technical problem and need to be solved. In this paper, to well Antaibao Union Industrial Square, the engineering practice of North Slope as an example, slope stability and consolidation design in the underground mining of the open pit are studied. The significance which can promote coal mining enterprises to make technological progress and ensure production safety is very important. Main research works are as follows:[1] Through on-site field research, information are collected and the impact of open pit slope stability factors are analyzed. Besides, applying FLAC and MSARMA methods,the deformation and strength of stability of open pit under underground mining are studied; underground mining will significantly reduce the slope stability, such as the case of saturated water or seepage, slope instability can easily occur.[2] According tu the reinforcement principles of the open pit slope, The reasonable and effective reinforcement method of open pit slope under underground mining are studied. The reinforcement principle and advantages of the prestressed anchor frame beam support system are analyzed, and the comprehensive management measures are proposed,such as drainage, slope cutting, stress and displacement monitoring;[3] The reinforcement design of prestressed anchor and frame beam to open pit slope are given. The design principles, content and method of prestressed anchor are discussed. The force characteristics and internal forces calculation method of the frame beam in the tension phase and work stage are analyzed. Besides,based on the actual condition of the slope engineering,the design of prestressed anchor and frame beam is carried;[4] Apply Slide software to analyze the stability of the reinforced slope and under underground mining. Prestressed anchor frame beam can significantly improve the stability of the slope, at the same time the toe and gob should be reinforced.The sensitivity response to the multi-rock slope steady-state under the underground mining of the rock material properties, seismic and groundwater and the supporting structure parameters is studied. The optimum design method is put forward and anchor is optimized.In this paper, slope reinforcement technology of prestressed anchor frame beam in open pit significantly improves the stability of the slope and guarantee the safety of mine production effectively, which is important for promoting and engineering applications.