Exact analysis of the plane-strain vibrations of thick-walled hollow poroelastic cylinders

The paper deals with the plane-strain vibrations of thick walled hollow, co mposite poroelastic cylinder. The frequency equations of axially and non-ax ially symmetric vibrations, each for pervious and impervious surfaces are o btained using the analytical model based on Blot's theory of wave propagati on in fluid-saturated porous media. In case of axially symmetric vibrations , dilatational and shear modes are uncoupled, while in non-axially symmetri c vibrations, dilatational and shear modes are coupled. The plot of frequen cy versus ratio of wall thickness to inner radius of composite cylinder for different materials is presented, and then discussed. For axially symmetri c vibrations, two limiting cases of ratio of wall thickness to inner radius of composite cylinder are considered, i.e., when these ratios are very sma ll and very large. The first limiting case corresponds to modes of thin por oelastic shell and plate, while in the second limiting case, modes of poroe lastic solid cylinder is obtained. Thus, the problem of axially symmetric v ibrations describes a transition from the case of plate, thereby thin shell to analogous pochammer case of poroelastic solid cylinder. The results of purely elastic solid are shown as a special case. (C) 2000 Elsevier Science Ltd. All rights reserved.