District Division Rules Of Excavation Disturbance And Reinforcement Technology Of Roadways In Deep Mine

The paper focused on “district division of excavation disturbance and reinforcement technology of roadway groups in deep mine” and taking 900 m buried rock development roadway group as the research object, based on extensive collection of data and long-term field tracking, used theory analysis, numerical simulation of method, industrial field tests and other comprehensive research means to expand the researches as follows:(1) Study on the stress distribution of surrounding rocks under the influence of adjacent roadway excavation disturbance: In view of the effect of large deformation of roadway excavation disturbed by adjacent roadway in deep mine, different mechanical models are established to analyse the stress distribution of surrounding rocks under the influence of adjacent roadway excavation disturbance.The rules include the stress distribution of surrounding rocks by single lane, adjacent roadways and roadway groups.(2) Influence of different horizontal and vertical distances on the disturbance effect of adjacent roadway excavation: FLAC3D5.0 numerical simulation software were used to simulate the influence of the disturbance of the roadway excavation on the first lane under the condition of different horizontal distance H and vertical distance V. According to the relationship between the vertical direction of adjacent roadways, three kinds of situations were putforward, V > 0(first lane is located above the post excavation roadway), V=0(first lane parallel with the post excavation roadway), V<0(first lane is located below the post excavation roadway). By analyzing the stress distribution, displacement and plastic zone of the surrounding rock of the first lane, the variation of the excavation disturbance effect with the change of the horizontal and vertical distances of the adjacent roadways were concluded. According to the spatial position relation of the adjacent roadways, the influence degree of excavation disturbance is divided into severe disturbance, moderate disturbance and weak disturbance.(3) Study on control technology of roadway surrounding rock with different disturbance level: In the light of hierarchical division of disturbance effects in different roadway layers mentioned above, numerical simulation software were used to simulate the supporting methods with different influence degree.Three supporting methods such as cable anchor, u-metal-bracket, floor bolt-grouting were simulated by single and combination form to comprehensive analysis and verify the validity of dynamic construction and combined support in the process of the excavation of the roadway groups from the field tests and the control effect of the roof, the rib and the floor of the roadway. Under the premise of meeting the safety production requirements, we should choose reasonable support methods to avoid to reinforcement and repair the roadway blindly which will waste a lot of manpower and financial resources.(4) Study on industrial tests and field measurement: On the basis of the research above, according to the case-885 east track roadway of Zhuji east coal mine severely damaged due to near roadways excavation disturbance, the whole set of technical scheme and the industrial process including the floor bolt-grouting was put forward to reconstr a surrounding rock closed bearing ring. Mine pressure monitoring of industrial tests shows that the tests of-885 east track roadway is successful, the dynamic consolidation method, which effectively restrain the initial and further deformation of the roadway, reduce the deformation of the ribs to 66.6% compared to the original, control the roof subsidence in 100 mm and the floor heave in 50 mm. The industrial tests proved “cable anchor, u-metal-bracket and floor bolt-grouting” was the effective control means to control the soft rock roadway groups in deep mine again. Also, reference and guidance are provided for effective control of this kind of roadway groups.