Inverse Analysis Of The Surrounding Rocks Of Tunnels And The Reinforcement Structures Using Numerical Simulations

Displacement inverse analysis has been more and more applied in geotechnical engineering. Because of the complexity of geotechnical engineering, many questions have been come into existence in the application of the displacement inverse analysis for tunnel engineering.This paper will by the numbers introduce the history and actuality of displacement inverse analysis, conclude the theory of displacement inverse analysis and FEM implement for elastic-plastic problem. This paper presents the application of displacement inverse analysis in tunnel engineering.Based on the Yinjiayan bi-arch tunnel engineering of the Hurong national highway trunk-line in Hubei Province Yichang (the Changjiang Rive bridge) to Changyan (Baishiping) highway , the thesis primarily discourses upon the numerical simulation analysis of the stability of the excavating and supporting during the bi-arch tunnel construction in the surrounding rock by the finite element method(FEM) calculation , adopting the elasto-plastic theory. Finally, taking the constructing Yichang (the Changjiang Rive bridge) to Changyan (Baishiping) highway as a case history, thecomputation of displacement inverse analysis is carried out, The elastic from the inverse analysis is used to process the normal analysisto supervise the tunnel construction.This paper focuses on 3 facets as below:1.Erecting analytic model by dynamical FEM (GeoFBA-V3.0),we will compute the stress and strain of surrounding rock and achieve displacement of underground carvern.2.Using several controlling points' actual displacement in underground cavern,the article adopt elastic-plastic theory. We can invert Young's modulus E of rock mass, acting on the side of computing model.3.Utilizing inversion results, we can verify the feasibility of the method of the article combining geological condition, constructive situation and monitoring data.