Da. Saravanos et Da. Hopkins, EFFECTS OF DELAMINATIONS ON THE DAMPED DYNAMIC CHARACTERISTICS OF COMPOSITE LAMINATES - ANALYSIS AND EXPERIMENTS, Journal of sound and vibration, 192(5), 1996, pp. 977-993
Analytical and experimental work is presented on the damped free vibra
tion of delaminated laminates and beams. A laminate theory is develope
d in which the unknown kinematic perturbations induced by a delaminati
on crack are treated as additional degrees of freedom. The generalized
stiffness, inertia and damping matrices of the laminate are formulate
d. An analytical solution is developed for the prediction of natural f
requencies, modes and modal damping in composite beams with delaminati
on cracks. Evaluations of the mechanics on various cantilever beams wi
th a central delamination are performed. Experimental results for the
modal frequencies and damping of composite beams with a single delamin
ation are also presented and correlations between analytical predictio
ns and measured data are shown. The effects of delamination vary based
on crack size, laminate configuration and mode order. The implication
s of the mechanics in developing delamination detection techniques are
also discussed. (C) 1996 Academic Press Limited