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| ANALYSIS OF PORE PRESSURE ACCUMULATION IN SATURATED SOIL INDUCED BY PILE VERTICAL VIBRATION |
| SHI Qian，LI Qiang，DUAN Weiwei |
| (Department of Civil Engineering，Zhejiang Ocean University，Zhoushan，Zhejiang 316004，China) |
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Abstract A non-coupling method is used to simulate the pore pressure accumulation in surrounding soil induced by pile vertical vibration. Firstly，an analytical solution of steady-state pore pressure built up by vertical vibration of a floating pile in saturated soil is obtained based on Biot?s theory of saturated porous media，considering the imperfect bonding condition at the contact surface of pile and soil in the course of pile sinking. A semi-analytical solution of transient pore pressure oscillation is deduced by using a convolution method and a numerical integration technology of the inverse Fourier transform under arbitrary sinusoidal excitations. Then according to empirical formula of residual pore pressure of saturated silty clay obtained from dynamic triaxial test，a connection between the steady pore pressure and the residual pore pressure is established in terms of shear strain and excitation times. Furthermore，the simulation of pore pressure accumulation of surrounding soil aroused by pile vertical vibration is successfully achieved. Numerical results show that the steady-state pore pressure distributions and pore pressure accumulations in the imperfect bonding condition are smaller than the ones in the perfect bonding conditions. The contact stiffness between pile and soil and the rigidity at pile toe have significant effects on them. Besides，the permeability coefficient of soil has obvious effect on steady-state pore pressure distributions.
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Received: 02 May 2013
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2013, Vol. 32 
