Vertical vibrations of a rigid circular cylinder embedded in a Poroelastic medium

Abstract

This thesis studies the steady-state vertical vibrations of a rigid circular cylinder embedded in a homogeneous poroelastic medium. The cylinder surface is assumed to be either impermeable or fully permeable, and perfectly bonded with the surrounding half¬space. The poroelastic half-space is governed by Biot’s theory for poroelastodynamic. The problem is formulated by decomposing the cylinder-poroelastic medium system into a real cylinder and poroelastic medium with a cylindrical cavity identical to the embedded cylinder. The appropriate boundary conditions are specified on contact surface. A coupled set of integral equations is established to determine the intensities of forces and fluid sources applied on the auxiliary surface defined interior to the surface on which boundary conditions are specified. The integral equations are solved numerically in the frequency domain. The kernel functions of the integral equations correspond to appropriate Green’s functions for a poroelastic half-space. The vertical impedance of a rigid cylinder are examined for different length/radius ratio, poroelastic material properties and hydraulic boundary conditions. The present results are useful in the study of dynamic response of embedded foundations in poroelastic soils.