Tunneling-induced Ground Unequal Settlement On The Impact Of Buildings

City tunneling will inevitably result in a loss of ground due to soil deformation and displacement into the opening.The tunneling-induced soil movement and deformation may do damage to the pre-existing buildings.With the development of economy and improvement of urbanization level, the bulidings in the surface become more and more dense, the value of the bulidings become higher and higer, the contradiction between the tunnel excavation and the bulidings in the surface is even stand out. Therefore the study on ground surface movement and deformation caused by tunnel excavation, analysis of the effect of ground surface movement and deformation on the bulidings in the surface, puting forward a relevant defense measure have a important significance for ensureing the safety and the normal usage of the buliding. Based on the excavation of Qingdao Jiaozhou bay submarine tunnel project,taking the frame strueture on the ground above tunnel as the researching object.The Paper focuses mainly on the influence of tunnel construction on the surrounding environment by means of theoretical analysis,model test and numerical simulation.Following researching work has been done.(1) In theory, the disturbance of the formation mechanism was analyzed;(2) This paper based on discussion of the research present status that the tunnel structure stabilization,obtained from the tunnel adjacent formation pressure introduced the adjacent formation initial stress condition as well as the adjacent formation loose pressure definite method.Through mechanics analysis which mutually affects to support structure the structure and the adjacent formation,has established the adjacent formation and support structure the structure state of equilibrium.Then,representing the tunnel structure numerical simulation methods and the analyzing course of the finite element,and analyzing ANSYS application at the imitation of the tunnel construction.Based on the excavation of Qingdao Jiaozhou bay submarine tunnel project,establishing the tunnel calculation model by ANSYS,using the elastic-plastic method and yield criterion of Mohr-Coulomb to simulate the cutting and supporting on cross-section ZK2+285 of this tunnel,obtained motion stress graph of each cutting step and the changing regular of motion stress about the cutting fore and after. (3) Using the finite element software ANSYS, which according to the building of different surface settlement trough will move with the deformation of the surface as the initial condition input program, The damage of the buliding is evaluated according to the value of the stress and strain.(4) Study the defense measure of the buliding caused by tunnel excavation from five respects including the tunnel construction, ground consolidation, anti-deformation of the structure, building strengthening and building design.Ensure the damage is the minimum,realize the coordination of tunnel excavation and building protection in the surface.