Structural Health Monitoring: State of the Art and Perspectives

Different authors have presented perspectives of structural health monitoring (SHM) for different applications and state of the art of SHM in aerospace, civil, and mechanical engineering, and for military applications in the JOM, June 2012 issue. The basic premise of an SHM system is that damages alter stiffness, mass, or damping of a structure and in turn cause changes in the system performance as well as dynamic response. The first key issue of SHM is to identify the existence of damage in structures so that required maintenance can be conducted and catastrophic failures can be prevented. This procedure can be referred to as damage detection. The most useful SHM techniques developed for the DoD and aerospace applications are vibration-based approaches and GW propagation-based approaches. Global health monitoring, which refers to the damage detection in the entire bridge structure, has been applied for the SHM of both concrete and steel bridges.