Study On Mechanical Characteristics Of Tunnel Surrounding Rock Pressure Arch

Based on the previous research basis,this paper starts from the influence of tunnel stability,and combines with the teacher's curriculum reform project(project name: "tunnel project" teaching content and curriculum system reform),Guiyang rail transit line on a certain working section for the research background In this paper,the research on the progressive development of the surrounding pressure arch of the tunnel is carried out by using field investigation,theoretical analysis,model test and numerical simulation.The main works are as follows:1.based on reading a large number of tunnel surrounding rock pressure arch on the related literature,in the construction site to conduct research,collect relevant data and related information,for the purpose of classification and sorting,further understanding of the effect of surrounding rock pressure of tunnel arch factors and construction process.2.On the basis of the above,the design and production of test model box,procurement of raw materials(Cao Gang,steel,tempered glass,paint and other components)for its production.3.physical and mechanical indexes of similar principle and the railway tunnel surrounding rock grade as the foundation,using the ZJ type DT-10 W type strain controlled direct shear apparatus,GDS static analyzer and three axis of Tianjin city building materials instrument factory move the instrument test model parameters of material mechanics,in several options to select material,barite powder,quartz sand and vaseline as the raw material,and the deployment of a series of experiments,the final mass ratio of 12:5.5:1 can meet the requirements of the test.4.Through the model test and the finite difference software FLCA3 D,the whole section excavation is carried out under different depth conditionsto monitor and observe the stress development and surface subsidence of the surrounding rock under different burial conditions.The stress variation law of the surrounding rock is summarized and verified.5.Based on the comprehensive test and analysis of model test and numerical simulation,the mechanical properties and surrounding rock deformation law of the surrounding rock of the whole section tunnel under different depth of tunnel are studied.6.On the basis of the above,the paper analyzes the variation law of the pressure arch of the tunnel and the development and change of the surrounding rock mass,and compares the test results of the physical test and the numerical experiment.It is concluded that the physical test is disturbed by the excavation machinery,The test results are somewhat accidental,but generally consistent with the general law.7.Finally,the problems and shortcomings of this study are briefly described.