On The Damping Analysis of Layered Beam Structures

Abstract

The present work deals with the improvement of damping capacity of layered bolted joint beam and sandwich beam with constrained viscoelastic layer. Damping capacity of structural element is an important design aspect. It enables to reduce the amplitude of vibration, increase the long-term reliability and fatigue life. So it is a great challenge for engineers and scientists to develop suitable damping improvement technique in the field of aerospace, automobile and other industrial applications. A lot of researches are going in this field. Damping offers an excellent potential for energy dissipation. Friction plays a vital role in energy dissipation in layered structure, which is greatly influenced by the roughness in between the layers. In this work the effect of surface roughness and bolt tightening torque on the damping capacity of layered bolted joint beams has been experimentally investigated. Based upon the experimental results, Taguchi principle and artificial neural network method have been applied to develop models to predict damping in bolted layered beam structures. The damping capacity in terms of modal loss factor has been studied for sandwich beams with constrained viscoelastic layer. The effect of core loss factor and core thickness on modal loss factor of the sandwich beam has been studied using finite element based model. Predictive models to estimate damping in sandwich beams have been developed applying Taguchi principle and artificial neural network method. Both Taguchi principle and artificial neural network method can be successfully applied to predict damping in layered structures.