The Comparative Study Of Theoretical Solution With Numerical Solution Of Pile-soil Coupling Vertical Vibration

Pile-soil coupling vibration theory is an important basis for the development of pile dynamical theoretical research, and existing pile-soil coupling vertical vibration theories are mainly concentrated in the analytical solutions of relatively simple pile-soil coupling model. For pile vibration problems in complex cases, it is difficult to solve such problems using the theoretical methods, thus numerical simulation methods are needed to solve such complex vibration problems. In this background, this article has carried on the coupled vibration of pile-soil analytical solution, numerical calculation and comparision the numerical and analytical solutions.On the one hand, this paper will carry on the analytical solution of pile-soil coupling vibration, and get the vibration characteristic of the foundation under vertical dynamic loading. On the other hand, this paper will use finite element software to simulate pile-soil coupling vibration problem, and obtain the results of the numerical models available, then compare the results with the theoretical solutions in order to analysis the accuracy of the simulation results, explore the feasibility of numerical simulation for pile-soil coupling vibration. The principal contents of this paper are as follows:(1) Accomploshing analytical calculation to obtain theoretical curves of three cases, including the pile-side soil is homogeneous, vertically heterogeneous and radially heterogeneous, and separately considering different variables, the rules of pile-soil coupling vibration.(2) The soil is assumed to be vertically layered, in order to improve the accuracy of theoretical model,"fictitious soil pile" model is present, which takes the place of viscoelastic model. Finally, numerical calculation results are compared with theoretical results.(3) Respectively using finite element software ANSYS to establish three numerical models which correspond to the theoretical models (the pile-side soil is homogeneous, vertically heterogeneous and radially heterogeneous), and apply viscoelastic constraint on the numerical model with the complex stiffness at the interface of pile and soil in theoretical calculation methods, then numerical results are obtained. Finally, numerical calculation results are compared with theoretical results to demonstrate reliability of the models.(4) Using ANSYS/LS-DYNA to create pile-soil coupled model, the soil is assumed to be homogeneous, draw the variations of curves at the top of the pile in time domain when the parameters of pile-side and pile-bottom soil change, and compare these curves with the one calculated in theoretical methods to explore the feasibility of the numerical model.