Effect of steel collars on the seismic behaviour of axially-cracked historical stone columns

This paper focuses on the behaviour of cracked granite and heavy stone columns subjected to rocking motion due to pulse type ground shaking. In this field, the effect of the presence of circular collars is analysed and discussed. The overturning spectra are determined, including the presence of the collars, showing their effectiveness in reducing the overturning risk. Comparisons are shown with numerical analyses and a simplified analytical procedure is proposed.