Detection and localization of small damages in a real bridge by local excitation using piezoelectric actuators

Detection, localization and estimation of small damage using piezoelectric actuators for local excitation is the main idea of this study. The theoretical background of an algorithm based on power spectral density (PSD) method suiting multiple damage detection is developed and verified experimentally with the field data obtained from a composite steel bridge. The method is based on only the output data from the accelerometers without the need for measuring the excitation force. Some damage scenarios were introduced to the test structure by releasing bolts from the members connecting the lower lateral members and the main longitudinal girder. The results indicate that the PSD method could identify the location and monitor small damage growth in structural members.