Interdisciplinary study for knowledge and dating of the San Francesco convent in Stampace, Cagliari – Italy (XIII-XXI century)

The Franciscan monastery, situated in the historic center of Cagliari (Sardinia), was founded in the thirteenth century, and transformed during the later centuries, up to the present day. The complexity of the case and the lack of objective data about its history has led us to carry out an interdisciplinary inquiry, in order to achieve a better knowledge of the building, preliminary for the drafting of a restoration project that respects all the signs that the time left. Starting from a deep examination of the indirect sources, turned out to be incomplete, the investigation continued with the execution of a survey with laser scanner and with the characterization of materials and related diseases of degradation. For the laser scanner survey we used a Focus 3D by Faro, versatile and lightweight instrument that allows to perform scans with high speed point acquisition and high accuracy. For management, elaboration and processing laser data we used the JRC 3D Reconstructor Software by the Gexcel srl. The characterization of the materials was performed on a reasoned sampling of natural and artificial materials, referring to masonry, interstitial mortars and plasters, carried out at strategic points, representative of the various phases of the construction. The samples were studied through mineralogical-petrographic methods with instrumental techniques for the analysis of component materials (OM, X-Ray diffraction). The data obtained, crossed with the results of the reconstruction of historical maps, of the examination of masonry techniques and of the analysis of pattern elements (arches, vaults, decorative elements), have facilitated stratigraphic analysis and helped to advance chronological reasoned hypothesis referring to the building.