FREE VIBRATION ANALYSIS OF SANDWICH BEAM WITH ELASTIC OR VISCOELASTIC CORE BY APPLYING THE DISCRETE GREEN FUNCTION

Abstract

A method of analysis of the free vibration of a three-layer sandwich beam with an elastic or viscoelastic core and arbitrary boundary conditions is presented. The characteristic equation of the free vibration is derived by applying the Green function which is obtained as a discrete solution of differential equations governing the flexural behaviour of the sandwich beam under the action of a concentrated load. By applying the characteristic equation, the behaviour of the free vibration of the sandwich beam with an elastic or viscoelastic core can be analyzed efficiently without a calculation by a trail and error method. It is shown that the numerical solution has uniform convergence and good accuracy, and the effect of the elastic or visoelastic core shear modulus and the depth of the core on the natural frequency and the loss factor of the sandwich beam are evaluated.