Research On The Large Deformation Support Control Techniques Of-950 Belt Roadway In Lujiatuo Coal Mine

Lvjiatuo coal mining depth is large,complex geological conditions,with the increase of mining depth,ground stress appeared more obvious,the roadway supporting and maintaining put forward higher requirements,especially in deep roadway,surrounding rock stress,deformation of roadway is big,poor stability,supporting often need to overhaul,the serious influence of mine safety production.Therefore,it is increasingly important to determine the scientific and reasonable form of roadway support.Through the investigation of stratum structure,the physical and mechanical properties of each stratum and coal seam are understood,and the distribution law of geostress is mastered.For ? class surrounding rock of roadway and ? class surrounding rock roadway support the status quo analysis,understand the current supporting problems;The compressive strength of the surrounding rock was 43.19 MPa and 32.59 MPa respectively,and the tensile strength was 3.16 MPa.The stability grade of surrounding rock was determined as V by BQ method,RMR method and Q system method.On this basis,the supporting mode was determined as shotcrete network support.Slurry injection was selected as cement slurry and grouting pressure was 1.5mpa.The fracture network model was established based on 3 dec software,and analysis the roadway with tension and shear failure is given priority to,and in the roof and floor all appear larger displacement deformation,cumulative deformation more than 8 cm,not supporting roadway does not have homework conditions were determined.The roadway stability of the two supporting schemes was analyzed.The conventional supporting roadway was able to maintain basic stability,but the bottom plate was still greatly deformed,with the maximum deformation exceeding 1.1cm,and the roadway was still likely to be damaged.After combined support,the roadway can remain stable with the maximum accumulated deformation less than 0.15 cm,which can keep the roadway stable for a long time and meet the requirements of safe operation.