Structural identification and numerical models for slender historical structures

In the present chapter the theoretical basis of different methods developed for the calibration of finite element models (FEMs) are discussed. In general, Model Updating techniques are based on the use of appropriate coefficients (sensitivity coefficients) that iteratively update selected physical properties (properties of materials, stiffness of a link, etc.) in such a way that the correlation between the simulated response and the target value could improve if compared to an initial value. The FE model thus obtained can be used for a detailed structural analysis with a greater confidence. Finally, an application of Model Updating to a case-study of a slender structure (the tower of the palace of the Province of Bari) is shown. The FE model of the structure, initially developed taking into account a codified approximate behavior of the materials, is first refined through the application of a method based on the sensitivity analysis and is then validated through a correlation with the experimental response of the structure measured during dynamic tests under an unknown input