Structural health monitoring and damage detection using a sub-domain inverse method

Health monitoring of modern complex structures poses new challenges as regards increased safety and operational reliability, while recent sensor technology opens up many possibilities for previously undreamt of methods of analysis. The need for different schemes or algorithms for damage detection, remote monitoring and continuous real time evaluation is increasingly pressing. In this work, a sub-domain inverse method based on the analysis of the wave propagation in structures is used for the identification of the damage response vectors, with an adapted minimum rank perturbation formulation for the calculation of the perturbation stiffness matrix of a damaged structure. Results show that simple experimental procedures can be utilized and several strategies can be adopted for fast monitoring or detailed analysis. Analyses in sub-regions or complete structures are possible and testing can be done under random excitations and with structural non-linear behaviour or unknown structural parameters. The proposed method of using smart structures with many embedded sensors is potentially useful for structural health monitoring and damage detection with almost no limitation on the type or distribution of the sensors.