Interval Analysis Method for Damage Identification of Structures

Abstract

description was adopted for the measured natural frequencies in this paper. Via the first-order Taylor series expansion, the interval bounds of the elemental stiffness parameters of both undamaged and damaged structures were derived by using the model updating based on the initial analytical finite element model. The damage can be identified by comparing the differences between the two models, where the quantitative measure of the possibility of damage existence in the elements is introduced. A larger value of possibility of damage existence implied a higher possibility of damage occurrence. The damage identifications for a steel cantilever beam and a steel cantilever plate were performed by the presented method, which is validated by Monte Carlo simulation. Moreover, the case of the multidamage identification, the number of the used natural frequencies, and the effects of damage level and uncertainty level on the damage detection were studied as well. The numerical results proved the validity and applicability of the presented interval analysis method.