Research On Advanced Support Technology Of Grouting Anchor Cable For 5308 Working Face In Changping Mine

Aiming at the problem of roof control of the mining roadway caused by the poor advance support effect of the fully mechanized working face of Changping Coal Mine,this paper takes the5308 working face of Changping Coal Mine as the engineering background,and adopts a combination of field measurement,laboratory test,theoretical analysis and numerical simulation.Methods,the advanced support technology of the working face was studied,the grouting anchor cable advanced support technology was used to replace the single hydraulic prop,and the field industrial test was carried out.The main research results of this paper are as follows:Based on the large deformation characteristics of the roof of the gateway in 5308 working face,it is determined that the roof belongs to Class IV unstable surrounding rock;Based on the elastic-plastic mechanics theory,the mechanical model of roadway surrounding rock is established,the roof failure characteristics of mining roadway are analyzed,the expression of the maximum plastic zone of roadway roof is obtained,and the range of roof plastic zone is deduced theoretically;The distribution law of advance abutment pressure is studied by combining theoretical calculation with numerical simulation,and the optimal advance support range is determined;The setting time,water separation rate,compressive strength and fluidity of grout under different ratios are measured through tests,and the optimal ratio of grouting material for roof advance support is obtained.The performance of this material under different water cement ratios is tested;Based on the COMSOL numerical simulation software,a three-dimensional seepage stress coupling model is established,and the influence of different grouting parameters on the slurry diffusion effect is studied.The FLAC numerical simulation software is used to study the distribution characteristics of prestress in the surrounding rock of roadway roof under different support parameters,and optimize the advance support parameters and grouting parameters of roof grouting;The field industrial experiment was carried out in 53081 roadway.The field industrial test results show that the roadway displacement is small,the roof separation is within a reasonable range,and the axial force of grouting anchor cable is within a safe range.The research of the paper shows that the grouting anchor cable type advanced support can replace the single pillar.Compared with the single pillar,the grouting anchor cable can improve the bearing capacity of the surrounding rock of the roadway,reduce the labor intensity of workers,and improve the support efficiency.Provide reference for lower advanced support.There are 53 figures,14 tables and 84 references in this paper.