On the behavior factor of masonry towers

A recently proposed numerical algorithm, for the pushover analysis of masonry towers, is here adopted for the evaluation of the behavior factor, entering the simplified seismic analysis of masonry towers, suggested in the Italian Directive for the assessment and reduction of the seismic risk of the cultural heritage. In order to consider, within a probabilistic context, the uncertainty of the mechanical and structural parameters involved, Monte Carlo method is adopted. The study indicated that the reduction factor of the seismic forces depends mainly on the acting stress over compressive resistance ratio. It is shown that the actual value proposed in the Italian Directive may be unsafe for high values of this ratio. Finally, an empirical formula based on the different Monte Carlo simulations is calibrated for the prediction of the behavior factor.