Interdisciplinary Knowledge for Conservation of Ruins: Stratigraphic Investigations of San Giovanni Battista Church (Sardinia, Italy)

The debate over how best to preserve and reuse ruins continues apace among academics around the world, remaining a still unresolved issue. In modern ages, different approaches have defined several solutions for rehabilitating these complex architectures. However, these do not appropriately consider their role of chrono-typological and material benchmark for the whole understanding of the fabric and consequent basis for their future sustainable enhancement. In particular, this is even more discussed in Sardinia where the high presence of ruined structures as well as the lack of documentary sources and funding has led mostly towards non-intervention policies. For these reasons, the present research contributes to this debate proposing an interdisciplinary methodology of knowledge specifically designed for buildings in a state of ruin. It involves different scientific areas: 3D survey with laser scanning technologies, archaeological graphic restitutions, stratigraphic surveys and classification of masonries types and diagnostic laboratory tests on materials (mortars, plasters, stones). The study highlights the valuable archaeological and documentary relevance of ruins for the understanding of their history, building technologies, materials and a state of conservation. It contributes to the definition of a design project, and to the identification of the typological and dimensional features referred to a specific context, also useful tool for dating coeval minor architectures, difficult to date. The investigation plan is here tested on the rural church of Saint Giovanni Battista (Bortigali, Sardinia, Italy), dating back to the XIII-XIV century and actually in a state of ruin. The case study is particularly representative of the complexity related to the investigation of Sardinian rural churches characterized by the lack of archival sources and an interesting variety of masonries types due to their different chronologies, even if it makes the buildings themselves the only available document for the comprehension of their constructive phases. The illustrated knowledge plan also provides a substantial contribution for the definition of possible actions for the conservation, re-functionalization and valorisation of these ruins.