Abstract:
Detection and localization of small damage of secondary structure which connects horizontally adjacent main girders of a real steel bridge structure, are dealt with in this paper. Local Excitation Method (LEM) using piezoelectric actuators is examined on the bridge to detect small condition change of structure. 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 real steel bridge. The method is based on only the output data from the accelerometers without the need to measure the excitation force. Some damage scenarios were introduced on the test structure by removing bolts from the members connecting the lower lateral members and the main longitudinal girder. The result indicates that the PSD method could identify the location and monitor small damage of a structure accurately. The algorithm also enabled damage detection at multiple locations of the bridge.
