Key Technique Study of Stability Control of Surrounding Rock in Deep Chamber with Large Cross-Section: A Case Study of the Zhangji Coal Mine in China

摘要: This paper is a case study on the key technique of stability control surrounding rock in deep chamber with large cross-section Zhangji Coal Mine China. Many investigations and field experiments were performed to reveal failure mechanisms chamber. It was found that cross-section, high situ stresses, zone construction disturbance main causes instabilities. For original supporting scheme, numerical simulation adopted analyze stress displacement during excavation support. There are concentrations at junction chamber, shaft lining, machine roadway. The maximum displacements 74.7 mm horizontal, 105.9 mm roof fall 29.2 mm floor heave vertical. Based results, structure optimization design has been completed. primary composed bolt, steel mesh, shotcrete anchor. secondary concrete lining double-layer reinforcement an inverted arch. shallow lagging grouting for reinforcing rock. three-dimensional grid arch developed independently. indoor model test showed can take advantages characteristics various materials through unique spatial network design, which improved whole bearing capacity. A experiment convergence monitoring conducted. measurement data two sides 60 mm 42 mm 200 days, respectively. stresses far less than yield strength, had higher safety stock. successful demonstrated optimized reasonable deformation effectively controlled.