THE STRUCTURAL CONSOLIDATION IN THE CHURCHES IN SARDINIA, FROM 1950 TO THE PRESENT. A BUILDINGS TYPOLOGICAL READING FOR A VIABLE CONSERVATION STRATEGY

An in-depth analysis of the consolidations carried out in recent decades in Sardinia shows the evolution of intervention methods on cultural heritage, marked by different approaches who have been going on for several decades. Based on pre-established theories or specific laws, the solutions adopted are not always able to establish a good balance between conservation need and appropriate security. Equally important is the fact that the structural consolidation becomes in these cases exclusively scope of intervention in emergency, since we are in contexts considered low seismic risk, so that is not imposed by the law. For this reason "Budget consolidations" are conspicuously absent in this circumstance: the evaluation of the costs and benefits of the two different approaches, that of emergency and of prevention, on the other hand, is particularly important, considering that this is a context particular, with the rare presence of cultural heritage not always very elaborated and with scarce resources. Starting by a simplification of the reality, with an unavoidable exemplification of the cases studied through a typological reading, it is possible to classify the churches according to the common characteristics of the geometry and combination of architectural elements, in order to achieve the identification of a viable method of analysis and intervention, both in the specific buildings studied, both in similar contexts. For each category we have identified the corresponding specific structural behavior, in order to plan a generic operational approach, universally valid, for all cases included in it, except that then must be followed by a specific intervention program for each particular case. It is thus a process of investigation and intervention methodology similar to that is applied in the area where the earthquake risk is high and, for obvious reasons, this is the most studied in Italy; so this metodology is nevertheless appropriate in contexts where this study is not investigated as it is need, although here the causes of the building vulnerability are different. The analysis of the structural behavior of historic buildings has been carried by the methods usually used in the architectural restoration, with the aim of a thorough knowledge of the actual structural behavior, with its on-going issues, also as a result of changes and stratifications that, since factors of influence, it need to know. The development of this method of analysis can be considered essential to ensure the most correct choice of the management strategy of the local cultural heritage, within a strategy of preventive conservation and planned, rather than emergency continues: the purpose of the analysis performed is to have a strategy for ensure the conservation of the architectural heritage widespread and, in particular, the churches, who are particularly vulnerable, considering their tendency to become gradually more and more unused, buildings that had interventions almost exclusively responsive to use needs, rather than the real structural requirements to guarantee its preservation.