A SIMPLE FINITE ELEMENT BASED MODEL FOR A CONSTRAINED-LAYER OF VISCOELASTIC MATERIAL (PART - 1): EXPERIMENTAL VERIFICATION AND COMPARISON WITH ANALYTICAL MODELS

摘要

In this article, a simple, finite element based model for a constrained layer of viscoelastic damping for beams is developed and implemented. The proposed model uses a series of discrete springs and dampers to model the stiffness and damping, and lumped masses to account for the mass of the viscoelastic material while the base material and constraining layers are modeled with a five-node Timoshenko beam element. The accuracy of the model is verified experimentally by testing damped beams with various damping treatment configurations. The results from the proposed model and the experiments are then compared with the Mead-Markus analytical model. Concerns over the accuracy of the Mead-Markus analytical model are raised and discussed. The results demonstrate that the proposed model can predict the fundamental natural frequency of damped beams to within 3.5 % or better of the experimentally determined values and that, with the exception of short and intermediate length constraining layers, the damping ratio can be predicted to within about 8 % of the experimental values under most circumstances.