An analytical model of free vibration of a delaminated composite laminate in prebuckled states has been developed. The formulation is based on a new constrained model which includes both effects of the compressive force and bending-extension coupling. These two effects on the natural frequency of delaminated plates have not been studied by such a model before. It is found that the compressive force, laminate lay-up, delamination length, and delamination locations in the thickness-wise and spanwise directions are significant factors to determine the vibration characteristics. Experiments have been conducted to validate this analytical model. Good agreements between the analytical results and test data have been obtained.
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