Forced nonlinear vibration of laminated composite plates with random material properties

Components in aerospace vehicles, automobiles, civil and mechanical structures that have requirements of high strength to weight ratio are made of filamentary composite laminae. These structures are usually subjected to stochastic loads during their performance. This paper deals with the nonlinear random vibration of a simply supported cross-ply laminated composite plate. The material properties and the external excitations are treated as random process. Using basic analytical techniques, this investigation aims at improving the accuracy of response evaluation of such plates by employing accurate models for the material properties and external loading. The formulation uses Kirchoff-Love plate theory and Von-Karman nonlinear strain displacement relationship. The system equation is obtained with Hamilton's principle. Closed form solution for the variance of the response is obtained by using first order perturbation technique. The results attempt to bring out the characteristics of the random response and its sensitivity to the lamina thickness and plate aspect ratio.