Research On Deformation And Support Technology Of Soft Rock Roadway In Qianxi Lead-zinc Mine

The support of soft rock roadway has been a major problem for the mine.Based in the West of Yunnan Province Lead-Zinc Mine roadway 860 main adit deformation is the most serious 120m-150m range as the research object,through in-situ direct shear test and indoor rock mechanics experiment that rock(stone)physical and mechanical parameters,and the data processing of engineering.Based on the results of field survey,the 3D finite difference FLAC3D numerical simulation software is used to analyze the deformation of the tunnel after excavation.According to the geological conditions,the paper puts forward three kinds of supporting methods,including the supporting scheme of anchor cable.From the aspects of stress,displacement and plastic zone,the three schemes are compared and analyzed,and the optimal supporting scheme is determined,which can provide some reference and reference value for the similar geological conditions in the future.The main contents of this paper are as follows:(1)On the soft rock roadway,especially the deformation characteristics of phyllite tunnel are analyzed and summarized.(2)To extremely phyllite fractured rock mass completed in-situ shear test,and by in situ direct shear test physical mechanical parameters of rock mass are phyllite.Based on the rock mechanics test,the physical and mechanical parameters of limestone are obtained,and then the rock mechanics parameters are determined according to the Hoek-Brown criterion.(3)On the basis of field survey data,the 30m tunnel numerical simulation software is used to model the FLAC3D tunnel with the most serious deformation.In this paper,the distribution law of stress redistribution and deformation law of tunnel in soft rock are studied.(4)The main supporting theory of bolt(cable)is enumerated,and the strength theory of surrounding rock is determined according to the actual geological conditions and simulation results.(5)By using the design manual and the engineering analogy method,the paper puts forward three kinds of support schemes for the tunnel,and uses FLAC3D to simulate the tunnel under the condition of three kinds of support.The support effect of different support methods is obtained,which can provide a basis for selecting reasonable support form.