DYNAMIC ANALYSIS OF AXISYMMETRICAL FOUNDATIONS ON POROELASTIC MEDIA

A boundary element method (BEM) is presented for the dynamic analysis of axisymmetric poroelastic media, subjected to time-harmonic excitati on. The integral formulation, based on the fundamental solution of Bio t's poroelastic theory, eliminates the need for domain discretization for piecewise homogeneous media and automatically satisfies the radiat ion conditions. Additionally, there is no special treatment required f or the incompressibilty that may result under undrained conditions. Th e axisymmetric formulation that is developed offers further reduction in dimensionality of the problem and provides a convenient framework f or investigating the behavior of circular foundations. The BEM algorit hm is validated via comparisons with an analytical solution for the dy namic response of a soil column under uniaxial loading and is then uti lized to study the dynamic compliance of a shallow circular foundation . The suitability of employing various quasistatic and elastodynamic i dealizations is considered in some detail.