REFLECTION OF FLEXURAL WAVES IN GEOMETRICALLY PERIODIC BEAMS

The paper focuses on the reflection characteristics of elastic beams h aving a periodically varying cross-sectional area. Assuming a weak sin usoidal variation of the beam cross-section along its axis, perturbati on methods are employed to determine flexural resonance conditions and analyze the resonant destructive interaction of flexural waves with t he periodic beam. This interaction is represented in the form of coupl ed-wave equations, which are solved analytically, together with releva nt boundary conditions, at the ends of the periodic section of the bea m. The reflection coefficient is then calculated for beams having diff erent types of periodicity. This study is intended to provide guidelin es to control passively the flexural vibration in beams. (C) 1997 Acad emic Press Limited.