Dual-type sensor placement for multi-scale response reconstruction

Abstract

Although various types of sensors are now available to monitor a structure, structural responses are usually recorded in a limited number of locations which are much less than the total number of degrees of freedom (DOF) of the structure. The lack of information on multi-scale responses of the structure at all its key locations may hamper subsequently the accuracy of system identification, the reliability of damage detection or the effectiveness of structural control. Therefore, multi-scale response reconstruction at the key locations of a structure based on limited measured responses is essential. A dual-type sensor placement method with the aim of the possibly best reconstruction of multi-scale structural responses is investigated experimentally in this paper in terms of a simply supported overhanging steel beam. The numbers and locations of strain gauges and displacement transducers for the possibly best reconstruction of the multi-scale responses are first determined in terms of the proposed method and the updated finite-element (FE) model of the overhanging beam. An experimental work is then designed with the simply supported overhanging beam. The determined dual-type sensors are installed on the physical beam accordingly. The structural responses from these sensors are recorded during the experiments and employed to reconstruct the multi-scale responses of the beam at all its key locations. Some of these reconstructed responses are finally compared with the measured ones to verify the proposed method. The results show that the proposed method is feasible and efficient.