Analysis On The Influence Of Rock Creep And Nonlinear Joint On The Mechanical Behavior Of Shield Tunnel

With the rapid development of underground engineering, the construction condition faced is more and more complicated in this progress. Rheological deformation caused by high ground stress is the main reason of surrounding rock damage while excavating the tunnel in high ground stress. As creep deformation is the major factor in the deformation caused by rheological deformation, it is necessary to take creep deformation into consideration when constructing tunnel in the high ground.stress. Meanwhile, the joints connecting the lining are the weakest part of the whole lining. Therefore, it is of significance for the shield construction to simulate the mechanical behavior of joints in reality.Based on the inclined shaft of long distance constructed by shield method and combined with National science and technology support project, this thesis studies the stress condition of tunnel lining in high ground stress. The research work is as follow:Use FEM software to simulate the homogeneous ring model, linear joints and non-linear joints of beam-spring model are simulated at the same time. Compare the characteristic of the stress condition in three situations and reveal the advantage of non-linear joints.Considering the creep effect of soft rock, use FEM software to simulate the homogeneous ring model and linear joints of beam-spring model, the deformation and stress condition of the surrounding rock and lining under the condition are analyzed.Introducing Burgers creep model, the mechanical behavior influence by rheological deformation and non-linearity of joint is achieved by simulating the non-linear joint in the model of beam-spring model.