Study On The Support Technique Of Large Cross-section And Soft Rock Roadway

Bijie city is rich in coal resources. In the past the majority of coal mining are small coal mines with the blasting mining technology and conventional mining technique,sothe roadway cross-section is small. In recent years with the merger and reorganization carrying on, coal mine production scale is expanding constantly, the comprehensive mechanized mining requires larger section of roadway. Inadequate understanding and lack of technical experience of large section roadway in coal mine, combined with the special conditions of surrounding rock, which causes the difficulty in roadway maintenance. Therefore, in view of Bijie city coal mine actual geological conditions to carry out the supporting technology research on the large cross-section and soft rock roadway has important theoretical value and practical significance.Taking haulage roadway of Honglin coal mine 39110 face as the engineering background,combining the research survey, theoretical analysis, numerical simulation and field test method, the failure mechanism of surrounding rock deformation and characteristics as well as supporting technology have been systematically researched. Paper expounds the roadway surrounding rock deformation and failure mechanism and analyze the main influence factors for large cross-section and soft rock roadways deformation and destruction of surrounding rock found that the section size and shape of roadway, the supporting method and parameters are the main influence factors. On the basis of this, the influence of cross-section size on the distribution of the stress, displacement and plastic zone of roadway surrounding rock have been researched in detail, and reveals that deformation characteristic of the large cross-section and soft rock roadway surrounding rock are pressure and deformation coming fast, large deformation and long time deformation. Bolt-net-anchor coupling support technology has been put forward for large cross-section and soft rock roadway and the surrounding rock deformation law was analyzed and studied under different support parameters that bolt interval, row space, bolt length and number of anchor cables are different. Finally the reasonable supporting parameters were determined. At last, the industrial testing and a series of observation were performed in haulage roadway of Honglin coal mine 39110 face. the deformation of roadway surrounding rock and the load of bolts and cables analysis results show that the surrounding rock deformation is small, and gradually stability, roadway surrounding rock control effect is remarkable By using Bolt-net-anchor coupling support and designed supporting parameters...