Holes Parallel To The Tunnel Construction Of Surface Displacement And Deformation Studies

The construction of the tunnel in the cities will inevitably impact on the ground buildings and underground pipelines, so it needs to study the ground displacement and deformation caused by the construction of tunnels. Tunnels ofen appear in the cities in the form of the double parallel ones. The surface displacement and deformation caused by the construction of double parallel tunnels is more complex than the single tunnel's. The second tunnel is usually constructed behind the first one, so the surface displacement and deformation caused by the construction of the first tunnel is influenced by the construction of the second tunnel, at the same time the surface displacement and deformation caused by the construction of the second tunnel is influenced by the construction of the first tunnel. In order to provide guidances and references to projects, it is necessary to study the surface displacement and deformation caused by the construction of double parallel tunnels.According to the collecting information of the surface subsidence caused by the construction of double parallel tunnels, this thesis analyses the surface displacement and deformation caused by the construction of double parallel tunnels with the methods of random medium theory, Peck formula and numerical simulation. This thesis includes work as follows:1. According to lots of collecting information of the surface subsidence caused by the construction of double parallel tunnels with earth pressure balance shield, mine construction and open shield, the characteristics of surface subsidence are analyzed.2. The surface displacement and deformation caused by the construction of the tunnels of right side and left side is calculated respectively by the uses of Peck formula and random medium theory, and the surface displacement and deformation caused by the construction of double parallel tunnels is obtained by the results above with overlay superposition method. The method, which is used to caculated the surface displacement and deformation caused by the construction of double parallel tunnels, is proved to be appropriate through examples.iu 3. A model of surrounding convergence of tunnel is selected as the displacement boundary condition to study the surface displacement caused by the construction of double parallel tunnels. These include:(1) Through the contrast between calculated values and measured values, the non-uniform convergence model, which is selected as the displacement boundary condition of numerical simulation, is proved to be suitable in the study of ground surface displacement caused by the construction of double parallel tunnels.(2) The influences of distance between the tunnels, tunnel depth and ground loss to the ground surface displacement caused by the construction of double parallel tunnels, is analysed, at the same time the mutual influencing chart can be got.4. A theory solution is discussed of the class of problems of an elastic half plane with double parallel tunnels, loaded on the cavity boundaries with uniform radial displacement. The solution uses complex variables and alternating method and successfully achieved by the program with computer. And the results are confirmed by a practical engineering case.