Effect of delamination size and location on natural frequencies of laminated composite beams

چکیده مقاله

In the present research, the effects of delamination size and location on vibration characteristics of laminated composite beams are investigated both analytically and numerically. In the analytical method, the delaminated beam is modeled as four interconnected Euler–Bernoulli beams and the constrained and free mode models are both simulated. The differential stretching and the bending-extension coupling are considered in the formulation. Analytical results are compared with finite element ones and available experiments in the literature. In finite element method, delaminated composite beams with different size and location of delaminations and various boundary conditions are modeled in commercial finite element software, ABAQUS, and natural frequencies are extracted from the modal analysis. Free mode model and constrained mode model are considered in modelling and simulation by using suitable boundary conditions, element types, interactions, nonlinearities and friction conditions. The numerical results are validated by analytical and experimental results available in the literature for some special cases. Finally, the generated database for different sizes and locations of delamination can be used to detect the existence of delamination in laminated composite beams and then specify the size and location of delamination.