Damage detection of a steel frame from shake table tests

In this paper is discussed the application of two approaches to the process of the vibration-based damage detection for an experimental steel frame. In particular, the first one is based on changes of the mode shapes, natural frequencies and stiffness matrices. The model based indexes require the use of two records, in the undamaged and damaged states, and do not account of structural nonlinearity. The second approach is a statistical analysis procedure where the derived three indexes are data-driven; consequently, they do not require any assumptions about the structural model but only the knowledge of the output signals in the undamaged and damaged states. The main goal of the paper is to experimentally verify the efficacy of the considered procedures with the support of the results of an experimental study performed on a four-story steel frame tested at the Carlton Laboratory of the Department of Civil Engineering and Engineering Mechanics at the Columbia University in New York.