Longitudinal Vibration Theory Of Pile In Sophisticated Soils And Its Application

Longitudinal vibration theory of pile is the basis of any kind of method in dynamic pile testing,which can be used to explain the dynamic reaction between pile and soil,the mechanics of pile testing,and to illustrate the pile testing curves.In this dissertation,on the basis of the existing work,the longitudinal vibration theory and the relevant properties of pile with defects and variation modulus in layered soils is studied,in which viscosity of pile material is considered and surrounding soils are simulated respectively with normal Voigt model,normal Maxwell model,general Voigt model and general Maxwell model. The main original work includes:1. With Laplace transformation,the solution for longitudinal vibration of a pile with variable cross-section is derived when surrounding soil is simulated respectively with normal Voigt model and normal Maxwell model.2. Under the condition that the layered soil surrounding pile can be simulated with general Voigt model or general Maxwell model,the mathematical equations for longitudinal vibration of a pile with self-viscosity is established in the form of integral transformation,and the corresponding solution is obtained by using impedance function.3. Based on the above solutions,the influences of soil parameters in different visco-elastic model and viscosity of pile material on vibration characteristics and time domain response of pile are analyzed in detail.4. The validity of the solutions developed is verified by comparing theoretical vibration curves of pile with actually measured ones.The work presented herein overcomes the deficiency existed in available theories for longitudinal vibration of pile induced by using simpler soil model for simulating surrounding soil. This develops the longitudinal vibration theory of pile and makes it more perfect.