DYNAMIC RESPONSE ANALYSIS OF A TWO DIMENSIONAL FLUID-SATURATED POROUS BEAM

Based on linear elastic theory and Biot’s theory for saturated porous media, the dynamic response of a two dimensional fluid-saturated porous beam is studied, in which the compressibility of solid particles and fluid and the viscosity of the pore fluid are taken into account. Using Fourier series expansion and solving the ordinary differential equations, a solution for the dynamic response of the two dimensional simply-supported fluid-saturated porous beam is obtained. By degenerating the beam into a single-phase two-dimensional solid beam, the presented methodology is validated by comparing the free vibration frequency of the beam with that of a Bernoulli-Euler beam and a Timoshenko beam. As a numerical example, the dynamic response characteristics of the free vibration and forced vibration of the beam under uniformly distributed harmonic load are analyzed. The influences of surface infiltration condition, pore fluid permeability coefficient, and loading frequency parameters, etc. on the free vibration, solid displacement and pore fluid pressure of the two-dimensional fluid-saturated porous beam are studied.