The conservation and protection of the Italian architectural heritage is a current and particularly interesting theme for the scientific community. A part of this historical heritage is represented by worship places made traditionally with masonry systems that result, nowadays, still open to the public.
In this work, particular attention is paid to the churches typology found within the “Sassi” UNESCO site of Matera. They are very often built with calcarenite masonry, a local rock also frequently named “tuff”, and show a high degree of seismic vulnerability also facilitated by many factors such as, for example, the material inhomogeneity, the low connections among the structural elements in conjunction with an inadequate maintenance status. In this paper the most vulnerable local collapse mechanisms of an ancient masonry church are at first individuated and, then, analytically evaluated. Two different approaches are followed: by using the classical kinematic linear analysis, and by simulating the nonlinear response of these macro-elements by the means of nonlinear pushover analyses. Moreover, in the paper some comparisons among the obtained results are shown
