The Research On Surrounding Rock Stability Of Large Span Coal Roadway And Supporting Technology Under The Mining Influence

With the sustained and coordinative，good and rapid development of the national economy，the coal resources plays a vital role for a long time；In recent years，because of the coal miningdepth increase gradually、geological conditions grows more complex、continuous introduction oflarge mechanical equipment、span of coal roadway constantly improved amidst the nationalwide，so the large span coal roadway with different degree mining influence grows day by day；In order to ensure the safety and years of service of the coal roadway，Developing a set ofsupporting system and parameters method aims to large span dynamic pressure coal roadway isparticularly crucial.In this paper，the author takes the typical large span dynamic pressure coal roadway inOrdos Gao Jia liang coal mine as main research object，which using theoretical analysis、sitemonitoring、numerical simulation methods to perform a comprehensive and systematic researchon large span coal roadway surrounding rock stability under the dynamic pressure and itssupporting technology； Achieving the following goals preliminary: the construction ofsurrounding rock stability evaluation system in the large span coal roadway under dynamicpressure，develops the surrounding rock deformation control countermeasures and correspondingsupporting technology，set up the joint security monitoring system aims to large span coalroadway，which are of great significance to guarantee the safety of coal production in China.Based on the basic situations introduction of the Gao Jialiang coal mine geological structure,land forms, stratum lithology and hydrological geology, through the field investigation,theoretical analysis, indoor rock physical and chemical test to analysis the damagecharacteristics、 the affecting factors of surrounding rock stability and supporting failuremechanism of the large span coal roadway under dynamic pressure；Finally，the surroundingrock deformation and failure mechanics mechanism of large span coal roadway under the mininginfluence is concluded；The paper expounds the surrounding rock stability classification methodsaims to large span coal roadway under dynamic pressure at home and abroad；then puts forwardto the fuzzy mathematics classification method，determines the overall classification indexes,analysis the indexes one by one, puts forward to the fuzzy clustering center, then focusing on thetwo and multiple times mining influences coal roadway，carry on a detailed surrounding rockstability classification aims to large span coal roadway under dynamic pressure；In reference tothe test method of surrounding rock loose circle both at home and abroad，this paper putsforward to the joint test methods which include hole examine and seismic reflection methods，then determines the surrounding rock loose circle size and its regularity of development; Based on the front works, this paper presents a dynamic information combined supporting system andparameter design method, comparing the advantages and disadvantages of all kinds of supportingscheme, and determines the initial combined supporting system; Through theoretical calculationand field investigation, the initial supporting parameters are concluded；In order to validate theinitial combined support system and parameters, this paper established a joint monitoring systemwhich includes the anchor (cable) actual forced monitoring、roof internal abscission layermonitoring、surface displacement convergence monitoring of surrounding rock aims to largespan coal roadway under dynamic pressure，this system can more comprehensive reflect the coalroadway surrounding rock pressure appearing situation, through the monitoring data feedbackprocess to adjust and optimize the support parameters， which can provides sciencedecision-making for final supporting system and parameter; Based on the basic hypothesis ofnumerical simulation, not only the simulation of the initial stress field of large span coal roadwayunder dynamic pressure is carried，but also the displacement and stress field respectively aims tothe combined support system are simulated，the results shows that simulation and monitoringvalue are very close，which validate that using large finite difference program FLAC3Dtoperform the numerical simulation is feasible and correct.The filed engineering practice shows that this combined support system and parametersaims to large span coal roadway under dynamic pressure are feasible in technology、reasonablein economic、reliable in safety、clean in environmental protection；what is more，the technicalroute and research scheme are correct, test methods and theoretical research are of innovation，which saved lots of money for Gao Jialiang coal mine，and achieved remarkable economic andsocial benefits.