Vertical dynamic characteristics of single pile with cushion cap undergoing free vibration
WANG Kui-hua1, CHEN Xin1, LV Shu-hui1, WU Wen-bing2, LI Zhen-ya1
1.Research Center of Coastal and Urban Geotechnical Engineering, Zhejiang University, Hangzhou 310058, China; 2.Engineering Faculty, China University of Geosciences, Wuhan 430074, China
Based on generalized Voigt model, the vertical free vibration of single pile with cushion cap was theoretically investigated by considering the viscosity of pile material. First, pile top the impedance is calculated according to the impedance transformation principle. Then, substituting the top impedance which serves as the supporting rigidity into the dynamic equilibrium equation of free vibration cushion cap, a semi-analytical solution for time-domain displacement curve can be obtained by using Laplace transformation and inverse transformation methods. Parametric study method was adopted to study the effects of pile diameter, length, material viscosity and different soil types on the free vibration characteristic of pile with exposed cushion cap. Finally, a comparison between the theoretical curve and the measurement values is conducted. The results of the present approach and the engineering practice show good agreement．
WANG Kui-hua, CHEN Xin, LV Shu-hui, WU Wen-bing, LI Zhen-ya. Vertical dynamic characteristics of single pile with cushion cap undergoing free vibration. JOURNAL OF ZHEJIANG UNIVERSITY (ENGINEERING SCIENCE), 2014, 48(9): 1595-1602.
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