Investigations on the band-gap characteristics of one-dimensional flexural periodic structures with varying geometries

Periodic structures have been studied extensively for their wave-filtering capabilities as they exhibit frequency band-gaps. The band-gap characteristics of flexural periodic structures, consisting of periodic cavities, depend on the geometry (shape and size) of cavities. The present work brings out experimental and numerical investigation of the effect of geometry of periodicity on the vibration characteristics of one-dimensional periodic structures. A procedure for prediction of the experimentally observed frequency band-gaps, with the help of eigenfrequency analysis, has been presented. Further, a novel concept of ‘real’ and ‘pseudo’ band-gaps has been theorized. Based on the experimental and numerical results, the best configuration of a periodic structure for maximum vibration attenuation has been arrived at. The work can find application in the design of frames and channels, made of periodic structures, where periodicity can be introduced to reduce vibration transmission in desired frequency bands. It can also reduce the requirement of extensive prototype trials for the selection of suitable periodic geometry.