Stability Research On Cables Waste Rock Concrete Cemented Filling Pillar

Abstract:It is accepted in mining sector that low-grade and gently-inclined thick ore body is difficult to mine. Achieving comprehensive utilization of low-grade mineral resources is a problem that we must face in mining development.It is gently-inclined, multilayer, heavy low-grade copper and iron deposits in symbiosis in Dahongshan Copper Mine. To take full advantage of these mineral resources, Yuxi Mining Corporation and Central South University proposed "Feasibility Study on Combined Exploitation of Copper and Iron in Yuxi Mining Corporation Dahongshan Copper Mine" program, adopted high break, large diameter mine collapse and subsequent filling mining method. The pillars in the project are100m in length,50m in height and5m in width, then filling with CIO waste rock concrete, simultaneously, arranging a long cable per meter in the longitudinal direction of the pillars, called cables waste rock concrete cemented filling pillar. Ensuring these pillars stable is one of the key of the project to success, so the main content of this paper are the mechanical action of cables in waste rock concrete and the stability of cables waste rock concrete cemented filling pillars.On the basis of summarizing previous results, this paper focuses on analyzing bond principle between cables and waste rock concrete, and then the mechanical action of long cables in the whole backfill pillars and the stability of the whole backfill pillars.Analyzing the stability of the pillar from two aspects:(1) with the knowledge of theoretical mechanics, considering the pillar as a girder with one ends fixed constraints and the other articulated constraints, then analyzing the force variation of the pillar in the height direction;(2) modeling on the pillar with the Finite Element Analysis Software Midas/Gen, analyzing the stress distribution and size in the interior of the entire pillar, and then the displacement distribution and size of the pillar.The results show:the largest stress that the pillar suffered concentrates on the bottom of the whole pillar, and the value is less than the compressive strength of waste rock concrete. Therefore the pillar will not be unstable because of its own materials damage. The maximum displacement appears in the central part of the entire pillar, the value is13.59millimeter, then gradually reduced to four weeks. So the pillar will not collapse to one side because the oversize transformation. Consequently, the backfill pillar is stable.Cables waste concrete filling is a brand new mining technology. Researching on the stability of the backfill pillars with different method, by comparing, getting a result that these pillars is stable, thus to ensure that the program can achieve the expected outcomes.