Research And Application On Structure Parameters Of The Backfill Roof For Stoping The Crown And Sill Pillar Residual Orebody In Fankou Lead-zinc Mine

Abstract:The key of crown and sill pillar orebody mining is the stability of the blackfill roof, A stoping mathod which used Trolley once drilling-blasting and used remote-controlled LHD to ore drawing was proposed in Fankou Lead-Zinc Mine. Ore body mining stope roof for blackfill roof, roof stability is the precondition of safety mining. This paper based on the research about Trolley Stope the Crown and Sill Pillar Orebody technology in fankou lead-zinc mine, on the basis of site investigation, literature consulting and field test, Carried out the theoretical analysis, mathematical method and the numerical simulation method, studied of filling technology、structure parameters and stability on backfill false roof, the main research contents and conclusions are as follows:(1)By using the method of laboratory test for mine filling material and the filling of the physical and chemical properties, mechanical properties and strength were studied, provide parameter basis for mine first layer backfill stability study.(2) Analyzed the main factors which influence the stability of filling body false roof, and the14major factors was assessed by the AHP methold. It is concluded that filling body strength, the thickness of the first layer backfill, the false roof exposure time, the influence of blasting and the filling technology were critical factors.(3) Analyzed the forces and loads calculation methods between room and pillar mining stope for the false roof; By using the thin board and beam theory to research the mechanics mechanism and instability mechanism of backfill false roof.(4) Proposed an efficient, low-cost first layer filling process, using bamboo instead of part of steel bars, verified bamboo ribs and steel reinforced false roof restorations feasibility(5) Using FLAC3D to simulate the different filling stope roof thickness of bottom column, the process of the filling room stope ground layers, the optimal thickness of2m, false roof pillar stope filling body between the optimal thickness is6m.(6) Select Fankou Lead-Zinc Mine Shn-320m SO-1#pillar mining stope as test stope, bottom column safety mining and roof of filling body are not major damage. Tests show that the first layer of filling construction technology and parameters meet the orebody stoping mining avoidances column of roof stability requirements.