In order to solve the surrounding rock damage problems of winch chamber in No. III I Mining Area of Yangzhuang Mine, such as, two sides getting closer, severe skin falling off the roof of pulp and serious floor heave, through the laboratory test, theoretical analysis and FLAC3D numerical analysis, the failure mechanism of the surrounding rock is studied. The results show that weak surrounding rock layers, a lot of clay mineral components and unreasonable supporting structure and parameters were the immediate causes for the failure, the excavation of old roadway around the winch chamber was the indirect cause, which provided scientific theory basis for the repair of the winch chamber and can be applied to the repair of similar mine chamber damage.
The winch chamber in No. III I Mining Area of Yangzhuang Mine was founded in 2006 bearing the III I Mining feeding task and discharging gangue. Since October 2010, field workers have found that there were some cracks in the winch chamber accompanied by stagging off, this phenomenon was particularly fiercer in March 2012. The layer of winch chamber roof fell off seriously, causing tuck net phenomenon obviously with reinforced metal mesh tearing and steel strip breaking. As shown in Figure 1, the floor heave of winch chamber became serious, leading to a serious distortion, and making the winch can't use normally. In order to ensure safety production and avoid the passive situation of the heavy casualties and the stagnation of production, we must study the failure mechanism of winch chamber and adopt comprehensive and effective measures to control it. The failure mechanism was complex. Many researchers at home and abroad have made a lot of researches and have gained great achievements on listening comprehension studies. Manchao He and Xiaoming Sun etc (He et al. 2002, He et al. 2004, Jiang et al. 2005, Jia 2006) put forward a standpoint that weak surrounding rock layers has a great influence on the stability of surrounding rock by analyzing the structure of surrounding rock. Lijun Han (Wang et al. 2005, Li et al. 2012) studied the influence on the stability of surrounding rock and concluded that high content of clay mineral composition was easy to cause damage of surrounding rock.