Safety Analysis Of Supporting Structure Of Severely Damaged Highway Tunnel And Research On Treatment Measures

Based on a severely damaged tunnel treatment project,this paper analyzes the impact of the thickness of the second lining defect and the back cavity defect on the safety of the tunnel structure on the basis of detailed investigation and detection of the tunnel diseases.The fuzzy analytic hierarchy process is used to comprehensively evaluate the safety status of the damaged tunnel.Midas gts/nx was used to numerically simulate the process of invert dismantling and secondary lining dismantling,studying the law of tunnel deformation and its influencing factors during dismantling and dismantling,and comparing and selecting different working conditions for dismantling and dismantling.Reasonable replacement suggestions.The research content of this paper can be used as a reference for the treatment of severely damaged tunnels.The main research contents of this paper are as follows:1.Carry out on-site investigation and data investigation of tunnel diseases,count tunnel diseases,and classify them into three categories: lining crack disease,lining defect disease,and tunnel bottom disease.The causes of tunnel disease are analyzed.2.Based on the on-site investigation and statistical results of tunnel diseases,analyze the safety of some diseases that affect the safety of the tunnel,including the thickness defects of the second lining and the defects of the initial support cavity,and use the fuzzy comprehensive evaluation method to comprehensively perform the safety of the tunnel disease section.Evaluation,the safety status of the tunnel section is "lesion".3.Use the general finite element software midas GTS/NX to numerically simulate the construction process of tunnel dismantling,analyze the deformation law of tunnel lining in the process of dismantling invert and secondary lining,study dismantling sequence,dismantling and replacing footage.The influence of the invert dismantling and replacement process,as well as the influence of dismantling and replacement footage,grouting range,and temporary steel support on the secondary lining dismantling and replacement process,compare different dismantling and replacement schemes,and give suggestions for treatment schemes that meet the engineering conditions.