Optimization Study On Roadway Support Scheme Of Shallow Thin Layer Uranium Mine In Weakly Consolidated Soft Rock Stratum

Uranium as an important strategic resource is mainly used in national defense construction and nuclear energy development.In Inner Mongolia,xinjiang,there are a plenty of uranium resources in the western region,such as formation in the majority with weakly consolidated formation in the mine.Due to the late diagenesis,poor cementation performance,low strength(uniaxial compressive strength < 1 MPa),easy weathering,cement disintegration and easy expansion of this formation,significant plastic deformation will occur under certain conditions,leading to serious destruction of roadway surrounding rock and increasingly prominent support problems.In this paper,the roadway with a depth of 70 m in a uranium mine in Inner Mongolia is taken as the engineering background,and the thickness of its ore bed is 1.5 m.The support technology,stress distribution and deformation characteristics of the surrounding rock of weakly cemented shal ow ore body are studied comprehensively by means of physical and mechanical test,numerical simulation and similar model test.The main research contents are as follows:(1)Basic physical and mechanical parameters of the surrounding rock are obtained through on-site sampling and laboratory tests,providing basic data for subsequent numerical calculation and analysis,study of similar proportions and model tests;(2)FLAC3D numerical software was used to build different models and analyze the deformation characteristics and plastic zone of surrounding rock when row spacing between 0.5m and 1.1m was used for U29 and U36 sections,so as to optimize the optimal supporting parameters;(3)Platt’s theory and ansys numerical software were used to analyze the stress of u-shaped steel support obtained by numerical simulation,to verify the feasibility of the support scheme;(4)Based on the similarity theory,the selection of fine sand as aggregate,gypsum as main cement,calcium carbonate as the auxiliary cement are adopted to simulate the hard and solid rock,and join bentonite to simulate Mr Has the character of swel ing rock and ore deposits,and conducted a series of 39 mechanics test,to find the ratio of 3 groups close to the physical model,provide data for subsequent model test research information;(5)The integrated use of digital technology,digital photography film sensors,and micro resistance strain gage measurement method,analysis of the optimal selection of supporting schemes under the surrounding rock deformation and failure process,the surface displacement of surrounding rock,the stress variation in the stress variation of surrounding rock and supporting artifacts such as law,used to guide the engineering field.The paper has 67 figures,22 tables and 107 references.