Influence of rock-socketed characteristics on the vertical dynamic impedance of rock-socketed pile
WU Wen-bing1,2, JIANG Guo-sheng1, DOU Bin1, WANG Kui-hua2，HUANG GEN-sheng1
1. Engineering Faculty, China University of Geosciences, Wuhan, Hubei, 430074, China; 2.MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering, Zhejiang University, Hangzhou, Zhejiang 310058, China
Abstract：Based on plane strain model and Reyleigh-Love rod model, the calculating model and governing equation of rock-socketed pile embedded in layered soil is established when there is arbitrary vertical exciting force acting on the pile head. Combined the boundary conditions and initial conditions, the analytical solution of vertical dynamic impedance at the head of rock-socketed pile is derived by means of Laplace transformation and impedance function transfer method. By means of parametric study method, the influence of rock-socketed characteristics on the vertical dynamic impedance of rock-socketed pile is investigated within the low frequency range. The results show that, for a certain depth of overlaying soil, the dynamic stiffness decreases as the rock-socketed length increases while the dynamic damping increases as the rock-socketed length increases. When the radius of rock-socketed segment is equal to pile radius, it can be seen that the dynamic stiffness and dynamic damping increase as pile radius increases. When the radius of rock-socketed segment is less than pile radius, it can be seen that the dynamic stiffness decreases as the radius of rock-socketed segment decreases, but the dynamic damping increases as the radius of rock-socketed segment decreases. It can also been shown that the dynamic stiffness increases and the dynamic damping decreases as the shear wave velocity of bedrock increases.
2014, Vol. 33 
