Formation Mechanism Of The Collapse Column Of 19109 Working Face In Jinggong No.1 Mine Evaluation Of Governance Effects

By means of field investigation and theoretical analysis,this paper studies the development sequence,structural style and characteristics of the strata in the region,explores the pore characteristics and development characteristics of the collapse column as well as the control mechanism of development,and studies the flow mechanism of different grout in the pores.According to the difference of grouting pressure and water-cement ratio,the mechanism of slurry flow and plugging was discussed,and the construction was organized with the exploration results,grouting and verification were carried out,and then safety evaluation was conducted to provide a basis for coal mining.This study achieved the following results:(1)Through the water head height,water temperature,water chemistry,the water inrush water source for the gray water,the water guide passage for concealed collapse column,discusses the mechanism of collapse,and mainly controlled by indosinian movement well-developed movement,at the same time,the study area is in the runoff area,structure and karst work together,is the fall of the key factors of the living.(2)Through COMSOL Multiphysics software simulation,the mud diffusion range was preliminarily obtained,which provided a basis for engineering design.The scope of the collapse column was checked: the top of the collapse column was developed 20.4m below the 9th coal floor,25 m below the 9th coal floor,the long axis was about 28 m,and the short axis was about 12 m.9 the horizontal long axis is about51 m and the short axis is about 30 m at 35-45 m under the coal floor.(3)The water source and water yield were found out: 5#-8# hole was the center,and local water came out from the 20.4-40.9m layer below the coal floor of 9.40.9m to 51.3m is the main water source area.According to the analysis of water volume,water pressure,water temperature and water quality test,the water source is ordovician ash water.The main outlet point is z3-2,which provides the basis for effective treatment.(4)According to the design of grouting end pressure at each stage,more than3.5mpa,all drilling grouting end pressure meet the design requirements,slurry diffusion quality is good.the grouting treatment and reinforcement layer is 15-45 m under the floor of 9 coal,forming a "water plug" of about 30 m collapse column,which proves that the water stop effect is good.(5)This project adopts various methods to test the treatment effect of collapsecolumn,including inspection hole observation,water quantity observation,water quality analysis and comparison,etc.Through grouting,"plugging" has been formed.The grouting thickness is 20-51.3m in hole no.5-8,and the grouting thickness is over12 m under the ordovish ash interface.The water passage of ordovician limestone water can be blocked to ensure the safe passage of 19109 working face.