Solutions for the seismic enhancement of a medieval tower

This paper deals with the assessment of the seismic vulnerability of the medieval civic tower of Soncino (Cremona, Italy) and the evaluation of possible retrofitting interventions to enhance the tower seismic capacity. The dynamic characteristics and the mechanical properties of the masonry tower are evaluated through a dynamic identification with ambient vibration tests. A finite element model of the tower is calibrated on the results of the dynamic identification. The vulnerability of the tower is assessed according to the italian guidelines for historical constructions performing a nonlinear static analysis. Different hypotheses of retrofitting interventions, involving the increase of the tower lateral strength or the increase of its dissipative capacity by means of dissipative devices, are investigated. The effectiveness of the proposed interventions is evaluated through nonlinear dynamic analyses, subjecting the structure, before and after the interventions, to seven artificially generated spectrum-fitting accelerograms.