“THE DURABILITY OF THE PATRIMONY BUILT THROUGH TRIALS AND EXPERIMENTATIONS ON SITE. THE CASE OF THE SASSI OF MATERA – ITALY”

In the intention of saving the historical sites is needed to put particular attention at the impact of the modernity with this particular ecosystems and give again life to the structures in respect of the needs connected with the modern living, without altering their character consolidated with time, with interventions correlated to the original building, typological, functional and technological characters. The present work was born from the will to realize an applicative methodology more respectful of the built, so as not to assist to a simple acritical transposition of the building conception, of the calculation models, of the materials, of the building techniques of the new architecture to the recovery interventions. In order to understand the technological and architectural evolution of the buildings of the past, and read through the rule of the art the gestures of the ancient builders, the Manuals and the Treaties edited from the origins to nowadays have been analysed. These are intended as sources and instruments of knowledge because every interventions on pre-existing structures is necessarily to start from the knowledge of the materials which compose them, and from the constitutive techniques of the period of their construction. In the intent of realizing interventions with a “predetermined” useful service life, they were analysed the materials of the tradition, their interactions and the possible phenomena of incompatibility to them bond. The methodology designed is based on a fundamental aspect of the project of recovery and/or restoration which is that cognitive, foreseeing investigation on site, through tests on site and in laboratory, the realization and then later on the validation of the intervention, through new tests and a periodical monitoring. The model proposed has been applied to a case study (The Sassi of Matera – Patrimony of UNESCO), emblematic site of the strong bind between architecture and natural environment, in which just because of the morphological conformation of the territory they were generated those architectures. Technological tests were executed to determine the physical chemical and mechanical characteristics of the materials used in the realization of the buildings of the Sassi (tufa, mortar, plaster) so as to evaluate the compatibility (chemical, physical, mechanical) with eventual new materials to use in phase of restoration and to validate the choices made during some interventions. This plan of surveys, accurately projected, presents as a further knowledge instrument and as a mean to programme any intervention of recovery in the respect of the ancient, without compromising the requisites of durability and safety. This research can also contribute to increment the casuistic of the tests to take on the masonry; in fact, in relation to all the problems which can enter a campaign of tests and investigations, it not only will be to think to an only kind of survey, but to an organic plan in which to compare the results, so as to have a conoscitive frame the more possible complete. Often only the compared analysis of more data, coming from different surveys, is possible to interpret the real phenomena and furnish the necessary parameters for the realisation of a correct intervention.