Between Safety and Conservation—Procedure for the Assessment of Heritage Buildings Based on Historic Research

Correct approaches to the assessment of historic structures involve the collection of data related to materials, building technology, eventual damage and decay, and transformation that has occurred over time. The procedure proposed by the authors is based on multidisciplinary research, merging data ranging from documentary and archive research to structural modeling. In the developed procedure, the minimization of the costs and timing of the structural assessment were the main requirements. The procedure, implemented on the Arengario, the 13th-century Town Hall of Monza, focuses on the key role of historic and documentary research in order to highlight the difference in the building technology. The overall research program involves the following steps: (i) historical analysis and documentary research; (ii) visual inspections, geometric survey, and decay/damage identification and mapping; and (iii) dynamic testing and modal identification, with these steps driving the choices involved in the subsequent step: (iv) FE modeling and updating.