Mechanism and key technologies of preventing rock burst by outward staggered entries arrangment in fully-mechanized caving mining face

Through the analysis of the problems in rock burst prevention at wide,narrow,no coal pillar section,an opti- mization scheme was proposed that the roadway section near goaf was arranged as outward staggered entries to reduce the danger of rock burst. Based on the model of overlying rock structure,the relationship of “low pressure zone and re- duction danger for rock burst” and “pressure relief protection and reduction danger for rock burst” was determined, which revealed the mechanism of preventing rock burst with alternate exterior entry layout pattern. So the reasonable position,supporting standards and principles were determined. The research findings were then applied in the thick coal seam with large burial depth (over 1 km) and strong rock burst tendency over the fully-mechanized top-coal ca- ving face at Huafeng coal mine. The study built the key technological system which takes the broken roof control,lia- ble-to-ignition control,efficiency of driving and mining,and reasonable early-warning into consideration. In this way, the prevention difficulty of rock burst and control difficulty of the deformation in roadway driven along next goaf,and the mining without coal pillar with large burial depth ( over a thousand meters) can be realized and solved. The re- search can serve as a reference in similar conditions.