A structural health monitoring (SHM) system provides an efficient way to diagnose the condition of critical and large-scale structures such as long-span bridges. With the development of SHM techniques, numerous condition assessment and damage diagnosis methods have been developed to monitor the evolution of deterioration and long-term structural performance of such structures, as well as to conduct rapid damage and post-disaster assessments. However, the condition assessment and the damage detection methods described in the literature are usually validated by numerical simulation and/or laboratory testing of small-scale structures with assumed deterioration models and artificial damage, which makes the comparison of different methods invalid and unconvincing to a certain extent. This paper presents a full-scale bridge benchmark problem organized by the Center of Structural Monitoring and Control at the Harbin Institute of Technology. The benchmark bridge structure, the SHM system, the finite element model of the bridge, and the monitored data are presented in detail. Focusing on two critical and vulnerable components of cable-stayed bridges, two benchmark problems are proposed on the basis of the field monitoring data from the full-scale bridge, that is, condition assessment of stay cables (Benchmark Problem 1) and damage detection of bridge girders (Benchmark Problem 2). For Benchmark Problem 1, the monitored cable stresses and the fatigue properties of the deteriorated steel wires and cables are presented. The fatigue life prediction model and the residual fatigue life assessment of the cables are the foci of this problem. For Benchmark Problem 2, several damage patterns were observed for the cable-stayed bridge. The acceleration time histories, together with the environmental conditions during the damage development process of the bridge, are provided. Researchers are encouraged to detect and to localize the damage and the damage development process. All the datasets and detailed descriptions, including the cable stresses, the acceleration datasets, and the finite element model, are available on the Structural Monitoring and Control website (http://smc.hit.edu.cn). Copyright © 2013 John Wiley & Sons, Ltd.

This work presents guided wave generation, sensing, and damage detection in metallic plates using in-plane shear (d36 type) piezoelectric wafers as actuators and sensors. The conventional lead zirconate titanate (PZT) based on induced in-plane normal strain (d31 type) has been widely used to excite and receive guided waves in plates, pipes or thin-walled structures. The d36 type of piezoelectric wafer, however, induces in-plane (or called face) shear deformation in the plane normal to its polarization direction. This form of electromechanical coupling generates more significant shear horizontal (SH) waves in certain wave propagation directions, whose amplitudes are much greater than those of Lamb waves. In this paper, an analysis of SH waves generated using in-plane shear electromechanical coupling is firstly presented, followed by a multiphysics finite element analysis for comparison purposes. Voltage responses of both the conventional d31 and the new d36 sensors are obtained for comparison purposes. Results indicate that this type of wafer has the potential to provide a simple quantitative estimation of damage in structural health monitoring.