Investigation on structural fault detection and location methods using vibration data

An investigation on some potential structural fault location methods using vibration data was proposed. The aim was to identify which methods were least affected by the adverse conditions encountered in real life vibration testing. The methods subjected to investigation were the total MAC, the sensitivity equations method using both eigenvalues alone, the sensitivity equations method using eigenvectors, both eigenvalues and eigenvectors, the Eigen parameter method, the modified error matrix method, and the force balance method. The investigation was carried out on the basis of numerical simulation using a theoretical discrete spring-mass system and a theoretical free-free beam, and practical modal testing using a free-free beam. Of the six methods which were subjected to the investigation, the force balance method was shown to be worth testing using experimental data. Both simulation and experimental results have shown in various ways that, for the type of structures used, the force balance method bears superior fault location capabilities compared with the capabilities of the others.