Study On The Ground Subsidence Mechanism And Its Influence Factors In Full-pillar Extraction By Backfilled Wide Working Face Layout In Strip Mining

Based on the project of recovery of pillar in strip mining with backstowing in Daizhuang Mine Zibo Mining Corporation Limited, combining with backstowing mechanics , mining subsidence and the theory about strata movement and its control, with engineering mechanics and numerical simulation, the thesis makes a study on the mining subsidence mechanism and its influence factor in full-pillar extraction by backfilled wide working face layout in strip mining.The paper makes an analysis on the main influence factors to mining subsidence in strip mining as well as the stability and function mechanism of backfill body in backfilling mining . combining with the key strata theory,the paper makes an analysis on the mechanism and feasibility of reducing mining subsidence of the technique and then get the main influence factors to mining subsidence in the technique. After a series of studies and analysises , the conclusion is drew that in a certain geological and mining condition , strength of stowing body ,width of isolating pillar and backstowing ratio are the main influence factors to mining subsidence in the technique.With the application of FLAC^3D, the paper simulates the stress field, displacement field and rock failure field in full-pillar extraction by backfilled wide working face layout in strip mining and that in the ordinary wide working face strip mining, then makes comparison of the simulation results.the paper simulates the influence degree to mining subsidence of strength of stowing body,width of isolating pillar and backstowing ratio.Ater that, the function curves between strength of filling body and mining subsidence, width of isolating pillar and mining subsidence, backstowing ratio and mining subsidence are got.