Structural damage detection using the estimated vibration response
Abstract »The damage index named Auto Correlation Function at Maximum Point Value Vector (AMV) which has been proposed by the authors previously, just needs the structural vibration response (displacement, velocity or acceleration) before and after damage to locate the damage. One can get the best detection results for the displacement response, while there may exist some false-positives when the acceleration response is used. But in reality it is much more easier to get the acceleration signals, so how to convert it into displacement and velocity signals is of great importance. A special estimation procedure to convert the different types of the response signals is utilized in this paper. The obtained acceleration response is first transformed into the frequency domain, in which it is converted to the displacement and velocity response, respectively. The estimated displacement and velocity signals are found to have only very small deviations from the real original ones, such that they can be used for the AMV-based damage detection method. Several cases of the stiffness reduction localization of a 12-story shear frame structure show that usage of the estimated displacement and velocity response gives better detection results compared to the original acceleration response. Furthermore there are no more false alarms, which makes the AMV-based damage detection method suitable for more applications.