Characteristics Of Deep Structure And Research On The Surrounding Rock Stability Of Roadway In Huize Mining Area

Huize Pb-Zn ore has more than 50 years mining history, with the exploration and mining depth increase, the geological environment become more and more complex, the increasing of broken rock, stress and water inflow, water inflow changes in complex which will be the key factors affect the stability of underground caverns. Therefore,in this paper the systematic collection and analysis on the basis of previous research, through on-site geological survey and laboratory analysis, summed up the deep structure characteristics of the mine area and its effect on deep exploration and mining tunnel, appling FLAC3D simulation method and combining with the original experiment to evaluate the stability of the surrounding rock.The deep structure of mining area are mainly developed with fracture, jiont fissure and a little folds. The direction of fracture developed mainly north-east direction and north-east, north and south and east-west and northwest, and complex changes of the fracture mechanics have taken place. Joint the mainly shear resistance, the mostly surfaces are flat and dry, filling material is mainly clay, calcite and filling is not thick.According to the site mechanical tests of different quality rocks, the physical and mechanical parameters were given, though the use of rock grading standards of engineering, conservancy and hydropower standard classification, internationally accepted classification RMR On the for grading the qualitative, semi-quantitative quality of roadway wall rock. Classâ…¢quality roadway wall rock which accounted for 72%,classâ…£for 24%;classâ…¤rock accounted for 25.4%, classâ…¡for 3.4%.The quality of surrounding rock are medium, basically guarantee the stability of mining tunnel, but partial area need supporting.Using F1AC3D to simulate and analysis the deformation and damage of the deep roadway surrounding rock, The results show that,the impact of horizontal stress of the roadway surrounding rock is greater than the vertical direction, level deformation range bigger than the rate of vertical; Stress redistribution after the tunnel excavation, As the role of secondary stress, Roadway deformation and damage stress decreased significantly in the first side wall and floor, two sides sink additional compression to produce rock deformation, and because the floor squeezing by the two sides,the deformation and damage arised with heaving floor.Through the situ experiments and numerical simulation results we can know, the rock compressive strength of situ experimental is greater than the compressive stress of the simulation rock formation, the results have a certain significance to future deep process engineering design of Huize Pb-Zn ore.