Damage Identification in a Plate Structure Based on Strain Statistical Moment

摘要

The fourth strain statistical moment (FSSM) based damage detection method has been recently proposed by the authors and the results of numerical study demonstrated the proposed method is sensitive to local structural damage but insensitive to measurement noise for beam-type structure. In this paper, the method is extended to a plate structure. The method consists of two steps: damage localization and damage quantification. First, the damage is located by using the difference curved surfaces of FSSMs in one direction of a plate subjected to Gauss White Noise (GWN) excitation before and after damage. Then the model updating method based on least square algorithm is used to estimate the damage severities. Also, the numerical (finite element) simulations are carried out for a simply supported plate. The results demonstrate the proposed method can provide good prediction of both location and severity of damage at one or more sites, even under low damage severities and high measurement noise conditions.