Structural health monitoring application of errors-in-variables identification

Structural Health Monitoring denotes a set of methodologies oriented to the description of the dynamical behavior of a structure in view of damage detection. These methodologies have taken advantage from the development of sensor, modeling and network techniques and constitute, today, a well established area. One of the most used methods consists in deducing dynamic models from the observations and in comparing these models with reference ones, concerning integrity conditions of the monitored structure. In many cases the excitations can be considered as white noise in the range of frequencies of interest and, in these cases, the structure can be described by means of autoregressive models. When this approximation is not realistic it is necessary to use input/output models that take into account also the characteristics of the excitation. This last case is considered in this paper making reference to the use of Errors-in-Variables (EIV) models and to data collected on a real structure during a small seismic event.