Abstract: When the parameters of the structures are uncertain, the structural natural frequ-encies become uncertain. In this paper, we deal with the vibration problem of the struc-ture with interval parameters, the eigenvalue problem of the structures with intervalparameters is transferrd into two different eigenvalue problems to be solved. The per-turbation method is applied to the vibration problem of the structures with interval pa-rameters, the numerical results show that lhe proposed method is sufficiently accurateand needs little computational efforts.

Key words: piezoelectric material, image force, interfacial crack, screw dislocation, natural frequency, interval parameter, matrix perturbation