The Analysis Of Pile Horizontal Deformation Caused By Shield Tunnel Excavation

Pile foundation is the most widely used form of the foundation reinforcement which is the most commonly used forms for the basis of the city buildings and bridges. With the huge bearing capacity, it can resist the complex loads, minish the settlement of the foundation and the superstructure. Meanwhile, with the further development of urbanization in China, as the most convenient urban transportation system, metro has been developed rapidly. Therefore, the subway tunnel, especially the shield tunnel is inescapable for the construction of the underground project to pass by the piles. Hence, it is a concern to study the influence of underground engineering construction, cut down the disturbance to the piles and soil so as to control the settlement and deformation of the pile foundation. Figure based on piles-pile load transfer function, the deflection equation and the pile-soil reflect, which aims to analyze the obtained deformation of the pile in the soil under the influence of deformation.(1)Given in the basis of analytical on the vertical displacement of soil solutions which due to shield tunnel by Loganathan, by introducing the concept gap parameters, and combined with load transfer principle, we can establish the pile-soil load transfer equation by using shear displacement under the action of shield tunnel. By fitting the quadratic non-followed by the differential equation method, the depth of pile arbitrary vertical displacement and axial force are obtained.(2) According to the pile axial force which is obtained by the level of soil analytical solution due to the shield tunnel excavation, we can assume the pile as the vertical placement of the flexible pile foundation beam and use Winkler assumed to establish the deflection curve of differential equations. We can use finite difference method to solve the equation, and to get a numerical solution of the level of the pile.(3) Deformation under four factors to the influence of pile, three types were selected representative of typical conditions and used the single factor analysis, we compared the different pile-bit, different foundation coefficient, different soil parameters and different slenderness ratio of the pile-soil relations, summarized the various factors of the column load, the level of pile axial force to the deformation and deformation of the pile. (4) According to pile group based on the displacement transfer theory, by analyzing the soil pile displacement transfer coefficient and combined with the earlier models, we can use the Matlab program to calculate actual condition of pile axial force and displacement distribution. Compare with the same location of the pile, we can analysis the axial force and deformation of the faster pile which was masked by the nearer pile.