Vertical Vibrations Of A Rigid Footing On Nearly Saturated Ground

Based on the Biot' s two-phase theory for fluid-saturated porous media, considering the inertia force of the solid and the liquid, and the coupling function between the solid and the liquid, and the compressibility of the liquid in allusion to the character of the nearly saturated soils. The dynamic governing differential equations are solved by Hankel transform. Then, considering the boundary condition, the dual integral equations of vertical vibration are established which are reduced to Fredholm integral equation of the second kind. The vertical vibration of a rigid footing on nearly saturated ground, nearly saturated stratum with an elastic superstratum, and a nearly saturated visco-elastic medium, is discussed in this paper.The dynamic compliance coefficients for the nearly saturated soils and the amplitude of the vibration of the footing versus the dimensionless frequency aO are presented in this paper. Numerical results indicate that, the influence of the vertical vibration induced by the saturation is high, even a slight decrease of complete saturation may lead to substantial change, the vibration which is induced by the height of the dry elastic layer is higher in high frequency than low frequency.