CROSS-TIME FREQUENCY TECHNIQUES FOR THE IDENTIFICATION OF MASONRY BUILDINGS

is paper explores the performance of some time-frequency bi-dimensional estimators in the identification of masonry structures. These techniques offer the advantage of being suitable for use in unknown input conditions, with no restrictions on the stationary character of the excitation. Hence, they are able to exploit the natural excitation of a structure, so that monitoring activities can be performed in normal service conditions, without making costly preparations on the structures. The second part of the paper concentrates on the identification of an old masonry bell tower on the basis of the accelerometer data acquired during the vibration transmitted by bells and wind and points out the advantages of the proposed method compared to the classical procedures.