ABSTRACT
Old buildings from centuries bear their own weight, and the loads due to their use and sometimes they have resisted the stresses of sudden violent events such as earthquakes. The old buildings in their long history are never equal to themselves, they have been sometimes affected by very incisive changes, which may be evident or less visible. The issue of the complexity of the buildings and of the modifications of the structures that follow each other over time, is well highlighted by the investigation on the cathedral of Siena and on the church of Monteluce in Perugia. A path of anamnesis and diagnosis is so developed as to reach a coherent understanding of the overall consistency of the artifacts, in which a more founded assessment and the evaluation of the behaviour of structures of the ancient buildings can be accomplished.
