Non-Linear Identification of the Seismic Damage in a Masonry Building from Dynamic Response Records

The identification of hysteretic degrading systems exposed to nonstationary loading is a paramount research topic, especially in the case of structures subjected to ground motion excitations. In this paper, the data recorded by a masonry building are used to assess its seismic damage. To better assess the mechanical characterization of the damage, a parametric non-linear identification is performed. To this aim, a Bouc-Wen type multiple oscillator model is adopted. Starting from the results of the calibration process a damage index based on the degrading stiffness matrix is defined.