Study On Static And Dynamic Response Of Pile Considering Cone Angle Of Virtual Pile

In this dissertation, the effect of cone angle on dynamic and static response of pile was studied. Virtual pile model is a new method proposed to solve the interaction between soil and pile. The soil among the pile and bedrock is assumed to "virtual pile". The vibration of virtual pile can be solved by one-dimensional bar theory, while the parameter of virtual pile was completely the same as soil. Compared with the traditional theory, the virtual pile model has certain advantages, mainly reflected in: You can give full consideration to the influence of multilayered soil; you can also consider the burying depth of bedrock; the parameter of virtual pile selection is also closely linked to the actual soil property.Based on virtual pile model, the following four tasks have been finished:1. Ignoring the radial displacement of soil and assuming that cone angle of virtual pile is a constant, the vibration of pile-and-soil system is investigated when harmonic force loaded on rigid circular plate. Then the bearing complex stiffness and dynamic characteristics are obtained. By analyzing Poisson's ratio, damping and some other factors, and comparing with other research results, the applicability and accuracy of virtual soil pile method in solving the problem of dynamic response of pile is studied.2. Assume that the soil under pile is single, by plane strain model a research on dynamic response of pile and soil is presented. By using complex stiffness method, the dynamic characteristics and complex stiffness in frequency domain is reached. Using the convolution theorem and Fourier inverse transform, the semi-analytical solution in time domain is reached too. Based on the above solution, the response of piles is studied under different conditions, and the solution is compared to fit with the engineering data.3. Assume that the soil under pile is single, by continuum model another research on dynamic response of pile and soil is presented. The effect of viscous damping is analyzed, while the solution under plane strain model and continuum model are compared with the same conditions.4. According to three-dimensional axial symmetry model, static equilibrium equation of pile and soil is built. By integral transformation, the settlement of pile top in frequency domain and time domain is obtained. The results are measured with project data.