Seismic analysis of a steel structure with viscous dampers for the protection of masonry towers

This paper presents a solution for seismic retrofitting of existing historical masonry towers, consisting of an internal steel structure equipped with dissipative devices that does modify the vertical bearing mechanisms of the masonry tower and does not alter its external architectural appearance. A historic masonry bell tower in the town of Fermo (Italy) is adopted as testbed structure to evaluate the potentialities of the proposed retrofit strategy. A finite element model is developed of both the masonry tower and the dissipation system and numerical nonlinear dynamic analyses are performed to investigate and compare the seismic response before and after the intervention. The outcomes of the study highlight the suitability of the proposed retrofit strategy in mitigating the seismic response of the upgraded structure.