improved method for damage detection in bridge girders or beams

improved method for damage detection in bridge girders or beams

bridge structures as a part of infrastructure and transportation network must operate safely. however, structures deterioration during their lifetime is unavoidable. by identifying structural damage in its initial stage, extra operational cost or catastrophic failure could be prevented. the accuracy of available damage detection methods depends highly on the quality of measured data of structure. generally, the number of used sensors is limited due to available funds, equipment, and accessibility to all parts of structure. the quality of measured data depends on the sensor location and location of excitation. thus, for successful damage identification, optimizing both the number and location of sensors and the location of excitation is essential. among dynamic characteristics of structure, the frequency response function has the highest sensitivity to the structural damage and has been utilized in many damage identification methods. in this paper, an optimization approach is presented to minimize the number of sensors and maximize the sensitivity of frequency response function of damaged structure. to evaluate the efficiency of the proposed method, a numerical example of bridge was studied. the damage detection results of the example enhanced by using the proposed approach for optimal excitation and sensor placement.