Free Vibration Analysis and Optimal Design of the Adhesively Bonded Composite Single Lap and Tubular Lap Joints

Abstract

ABSTRACT This study focuses on the three-dimensional free vibration analysis and modal stress analysis of adhesively bonded composite single lap and tubular lap joints subjected to clamped-free conditions, and on the effects of fiber angle, fiber volume fraction, overlap length, plate/tube thickness, and tube radius on the natural frequencies and the mode shapes of adhesive joints using the back-propagation artificial neural network (ANN) method. Free vibration and stress analyses were carried out using the finite element method for random values of fiber angle, fiber volume fraction, overlap length, plate/tube thickness, and tube inner radius, so that the proposed ANN models can be trained successfully to predict the natural frequencies as well as the corresponding modal strain energies. The ANN models indicated that fiber angle was a more dominant parameter than fiber volume fraction on the natural frequencies and corresponding mode shapes, and plate/tube thickness, tube inner radius, and overlap length were important geometrical design parameters, whereas the adhesive thickness had a minor effect. In addition, genetic algorithm was combined with the trained ANN models to achieve the optimal joint design that satisfies maximum natural frequencyCONTENTS10.1 Introduction 252 10.2 Dynamic Equations of Motion 255 10.3 Micromechanics of Composite Materials 256 10.4 Free Vibration Analysis of Composite Single Lap Joint 258 10.5 Composite Tubular Single Lap Joint 271 10.6 Conclusions 286 References 288