Research On Surrounding Rock Stability And Its Control Technology Of Multi-layer Composite Strata Main Road In Shilawusu Coal Mine

The coal main roadway in Shilawusu coal mine has large cross section and its. buried deep is 650 m around. The overall strength of surrounding rock is low with developed layered joints. The roof of main roadway is multi-layer soft and hard interbedded composite strata with developed joints in layer, which result in the roadway difficult to support. In this paper, crossing coal seam main return way was took as the research object, and surrounding rock deformation law and supporting technology of multi-layer composite strata was studied by using combining method such as laboratory experiments, theoretical analysis, numerical simulation and field measurement.First, through rock sampling, the physical and mechanical parameters of field rock samples were tested, the results showed that the overall strength of rock is low,belonging to the fragmented soft rock. Secondly, according to the theoretical analysis, deformation and failure regularity of composite roof was researched on, and the block structure stability conditions of fragmented rock was studied. Flac3 D numerical simulation software was used to establish three-dimensional calculation models of multi-layer composite rock tunnel, which simulated the deformation rules and supporting effect of the main roadway under different section shapes, spans and heights, and strata sequence after excavation. Combined with numerical simulation results and field specific conditions, the supporting scheme for the main roadway was formulated, and it was designed in the field for industrial research. Finally, the observation stations were deployed in the main roadway the field to monitor the application situation. The monitoring results show that, a certain deformation had occurred in roadway surrounding rock, but on the whole it had been effectively controlled.In this paper, research methods and research results on deformation and supporting of multi-layer composite strata roadway provided theoretical and technical support for Shilawusu coal mine, a scientific basis and technical means for the similar surrounding rock control.