Furong Cable Tunnel Typical Section Stability Study

Tunnel excavation causes the formation of stress distribution, regarding the underground structural engineering,the plastic deformation and loses stably both has the relation, but is not the same level concept. the plastic deformation appears certainly not to mean the structure's destruction. But it indicates certain rock bodies stresses have achieved or surpassed its capacity, demonstrates the structure has to loses the possibility and the tendency which the steady direction develops. Therefore, through the plasticity submits of characteristic, not only may carry on the rock body stability judgement and the forecast, moreover also is the rock body supporting design important basis. In addition, the plastic rock accompanies to the plastic tunnel space displacement. In particular, the high stress environment of soft rock, show a significant plastic Confucianism change . Thus, the stress and displacement of the flexibility-plastic rock analysis is the focus of this thesis. Rely on finite element analysis software to have the numerical simulation about a municipal tunnel project which have been involved in the construction and scientific research . Combining with the measurement of data, mainly from the following aspects of the stability of the tunnel.(1) By choosing three typical tunnel sections, when it is in deep and shallow status of full excavation, do research of tunnel different span and different depth of stress, displacement, the initial Lining endogenic force changes.(2) Using equivalent replaces circle method, carrying on the fo rce and the distortion analysis to two kind of typical section tunnel s, the result dicated this law is feasible. Comparing the finite eleme nt numerical method, work load is greatly the reduction.(3) Simulating in complex geological situation in tunnel excavat ion process force and displacement change rule.(4) Simulating the endogenic force and the displacement change situation when tunnel excavation established the protections anchor rod(5) Simulating lining of tunnel which has the quality flaw endogenic force, distortion change rule; the result indicates that the arche and theledger wall concrete thickness is very big regarding the wall structure axle strength influence, it is also bigger to the wall and the arche intersection place shearing force influence , the wall and the arche intersection place to the wall Level direction displacement influence is also big.(6) Quoting the stochastic medium theoretical to calculate twotypical sections the near surface of ground subsidence values, to calculatethe surface of ground subsidence value by using the finite element planenumerical analysis method, taking the computed result which throughthese two methods and the measured data to make the comparison.Reorganizing and analyzing the actual gauging data which is not verygood geological shallow submersion section working condition, useddifferent method to carry on the return analysis to the gauging data,using based on smallest two rides the non-linear law to carry onprocessing to the actual surface subsidence data, the result indicates thislaw the fitting precision is higher.