Study On GFRP Bolt Support Under Contact-zone Of Ore And Rock In Daye Iron Mine

Daye Iron Mine ore body is mainly produced in contact zone of the diorite andmarble, Sublevel caving method is used as mining method, there are a large number ofmining preparation and cutting roadways through contact zone of ore and rock. Theconventional way of bolt support is difficult to control the deformation and destructionof roadway, because the gap of convergence speed and the deformation of roadwaybetween ore and rock is large.Based on FLAC3D, roadway excavation numerical model of contact zone of oreand rock was established, rock mass failure strength theory is applied to analyze thedestruction mechanism of roadway of contact zone of ore and rock that including stressand displacement mutation, tectonism, shearing and expansion of rock mass, etc.According to the problems of existing way of slit wedge tubing bolt support thatincluding corrosion failure, pore size enlargement failure, the end stress failure andorifice damage failure in roadway of contact zone of ore and rock, on the basis ofroadway damage control mechanism of contact zone of ore and rock, supporting methodof GFRP Bolt sparging and anchoring net of contact zone of ore and rock is put forward.According to the principle of similarity theory, GFRP bolt anchoring force test underdifferent anchorage time, anchorage materials, anchorage length is conducted, the wayof anchor agent full-size grouted is selected that meet the supporting requirements ofroadway of contact zone of ore and rock in Daye Iron Mine. On the basis of numericalsimulation of influence degree of deformation and destruction of roadway underdifferent support parameters, the method of orthogonal test is adopted to confirm theoptimal supporting parameters of ore and rock which anchor length is1.8m, anchordiameter is18mm, bolt between row spacing is600mm,800mm and pre-tighteningforce is40KN in powder ore zone, bolt between row spacing is900mm andpre-tightening force is10KN in Diorite. GFRP Bolt sparging and anchoring netsupporting application testing research is carried out in typical roadway of contactbetween poder ore and Diorite in Daye Iron Mine, the results of testing and monitoringshow that support scheme control effect is good on surrounding rock deformation.GFRP Bolt sparging and anchoring net is adopted to support roadway of contact zone of ore and rock in Daye Iron Mine, not only can effectively control the non-uniformdeformation to guarantee the stability of roadway, but also can decrease supporting costand reduce the labor intensity of support,it has the great application promotion value.