Study On Reasonable Coal Pillar Width Of God-side Entry Driving And Roadway Supporting Technology

Based on the ShuoZhou Shanxi Province Nanyang slope large mining height, relying on "Optimization design and reinforcement technique and dynamic pressure coal pillar under the influence of safety monitoring of research" (NO.2013 FSX064), using theoretical analysis, numerical simulation and field monitoring method undertake a study on coal pillar deformation characteristics and roadway surrounding rock control technology. In view of the Nanyang slope mining special case, through the research of the project, to establish a complete set of optimization technology of coal pillar optimal design and tunnel safety monitoring research, for the Nanyang coal mining to provide reliable theoretical and technical support. The article studies the main content and research results are as follows:(1) This paper discusses on the distribution of the stress state of coal pillar, analyzed chain pillars between sections of loose zone and the plastic zone around the coal pillar and the original rock stress distribution zone. Through the rock under uniaxial compression test, based on the shear strength theory, obtained the basic physical and mechanical parameters of rock and coal, combined with the related theory and test data, calculated and coal pillar width of 3# and 5# layer.3# layer theory calculation results for 13 m,5# layer theory calculation results for 19 m.(2) Using the MIDAS GTS to simulate coal pillar stability of 3# and 5# layer design, analysis of the displacement of the roadway roof, floor and the state department. Determine the appropriate layer 3# coal pillar width is 15m, the appropriate layer 5# coal pillar width is 25m. And analyze the 3# layer recovery to 5# layer of the influence of roadway stability. The results show that:If 5# layer coal pillar arrange under 3# layer coal pillar,5# floor roadway stability affected by 3# layer recovery, bad for roadway supporting. The most adverse position is roadway below the coal pillar, the roadway stress too much, maintenance difficulties and easy to damage. Appropriate stagger arrangement coal pillar of different coal bed, benefit of stability of coal pillar and roadway maintenance, coal pillar center stagger distance appropriate is 60 m.(3) Using MSC-400 anchor (rope) dynamometer and convergence gauge to monitor anchor rod (rope) stress and roadway deformation with digital display section 1 and section 2 of the 3# layer. Monitoring results show that:anchor bolt stress stability after 23d, anchor cable stress stability after 20d. In the middle of the roadway roof bolt (cable) is the largest stress. Station in the process of drivage in surrounding rock is gradually increasing tendency for short-term incremental began to decrease, the whole process of deformation are small. Monitoring results show that:combined with relevant theory of the "anchor-net-belt" form of supporting of roadway supporting is very effective, coal pillar width is reasonable.