Abstract:
Based on the elasticity and theory of saturated porous media,regarding the pile and the soil as a single phase elastic medium and a saturated viscoelastic medium,respectively,the dyn amical behavior of vertical vibration of an end-bearing pile in a saturated viscoelastic soil layer was investigated in frequency domain with the Hemlho ltzdecom position and variable separation method.The axisymm etrical analytical solutions for vertical vibrations of the pile in a saturated viscoelastic soil layer were obtained,and the an alytical expression of the dynam ical complex stiffness of the pile top was presented.The responses of dynamic stiffness factor and equ ivalent damping of pile top against the frequency are shown in figures by means of the numerical method,and the effects of the saturated soil parameters,modu lusration of the pile to soil,slenderness ratio of pile and piles.Poisson ratio,etc.on the stiffness factor and damping are examined.It is shown that,due to the effect of the transversal deformation of the pile and the action of radial force of the saturated viscoelastic soil to the pile,the dynamic stiffness factor and the damping derived from the axisymmetrical solution are greatly distinct from those derived from the classical Euler-Bernoullirod model,especially at some specific excitation frequencies.Therefore,there are some limitations for the applicability of the Euler-Bernoulli rod model for analys is of the vertical vibration of the pile,and themore accurate analysis should be based on the three dim ensionalmodel.