Analysis And Optimization Of The Vibration Response For Fiber Reinforced Composites With Laminated Structure

The use of fiber reinforced composites has become widespread recently because of their high stiffness, high damping and low density. The excellent damping in polymer composites plays a significant role in reducing the nose and the vibration in mechanical and structural systems.This paper made the following three areas of research for composites laminates:Firstly, a mathematic model has been proposed for predicting the dynamic properties of uni-direction composites laminates with interphase. Dynamic properties mainly include loss factors and elastic moduli. Then the results of elastic moduli from the present model have been compared with other models. The effect of fiber volume fraction, interphase volume fraction and Young's modulus and loss factor of interphase on dynamic properties in composites laminates has been carried out here.Secondly, by the use of Hencky plates/shell theory, the finite element dynamic analysis models of the composites laminates has been established. Meanwhile, the modal experiment has been done for different laminates, and the results show that the prediction models of loss factor of composites laminates are valid. The influence of length of plates on the nature frequencies and mode shapes has also been studied.Lastly, the dynamical differential equations have been solved by use the method of Newmark-? and multi-front. The effect of ply stacking sequence and the layers number on the vibration response, the first modal frequency and SDC of the composites laminates. And the genetic algorithm(GA) is applied to the stacking sequence optimization of composite laminate plates that have the specified layer and angles, to satisfy the requirements of the vibration response.This research has a certain reference value on predicting the dynamic properties of uni-direction composites laminates. The vibration characteristic of laminate plates with any layers and angles can be conveniently got through the dynamic model. By combining the Newmark-? and multi-front method, the vibration response of composite plates can be calculated rapidly at the condition of different boundary.