Stability Analysis And Structural Parameter Optimization Of Stage Filling Stope In Steeply Inclined Thick Large Orebody

With the development of mining industry,the difficulty and cost of underground mining is far higher than that of open-pit mining.In order to recover the underground ore body safely and efficiently,the open field filling method has become one of the main choices in underground mining,and it is widely used in the mining of large-scale deep metal mines in China.Due to the late start of open stope subsequent filling method,although many underground metal mines at home and abroad have used open stope subsequent filling method in recent years,the application degree is not high.In the face of the rapid development of open stope subsequent filling method,the research on open stope subsequent filling method is slightly delayed.In this paper,the stability and structural parameters of stope between No.6 and No.12 exploration lines are studied based on the engineering background of a steeply inclined thick ore body.At present,the height of the middle section of-450m is 60m,and the mining work is coming to an end.With the continuous pursuit of economic benefits,the mining enterprises put forward the plan to increase the height of the new middle section of390m,and plan to increase the height of the new middle section to 90m.In this paper,similar materials and numerical simulation are used to study the stope stability of the new middle section,and the stope structural parameters are optimized.The following is the specific work of this paper:(1)The characteristics of similar material aggregate and binder are analyzed and summarized.According to the rock mechanical properties and similar material characteristics of mining area,river sand is selected as coarse aggregate,barite powder as fine aggregate and paraffin as binder.(2)The physical and mechanical parameters of standard samples of similar materials with different proportions were tested to select a reasonable proportion scheme for large-scale similar material test.(3)According to the selected proportion of similar materials,a large-scale indoor similar material test was carried out.The influence between the previous stage mining and the panel was considered in the test.The filling process of two-stage multi panel mining was restored in the physical model.The stress and deformation monitoring methods were used to analyze the stope stability and the stress and deformation law of the pillar roof.(4)Based on the three-dimensional numerical modeling of multi panel in the middle section of-450m and-390m between No.6～No.12 exploration lines,the influence of pillar width,room stage height,stope span and stope filling sequence on stope internal stress,deformation and plastic zone was analyzed by FLAC3D numerical simulation software.According to the analysis results,eight kinds of stope structure parameters are set for optimization analysis,and the optimal stope structure parameters are obtained.