Full Section Supporting Technology for -200 m Level Pump Chamber Group in Xiandewang Mine

In order to solve problem of large deformation and failure in -200 m Level pump chamber group of Xiandewang Coal Mine, the deformation reason is analyzed by site survey. Besides, the stress field disturbed by chamber excavation is divided into stress unloading circle, strong stress concentration circle, less strong concentration circle and stress stability circle from the outside to the inside according to stress concentration degree. On this basis, the theory of double shell reinforcement is proposed. The support shell formed by the shallow and deep support body ensures the chamber stability. At last, combined with the practical situation of -200 m Level pump chamber group, the support scheme of bolt (anchor) combined with the grouting and angle anchor beam and inverted arch is designed. The field application shows that this support scheme achieves good control effect.