CONSERVAZIONE, SOSTENIBILITA’ E RESILIENZA DEI CENTRI STORICI: IL COMUNE DI ARSITA (TE) E LA CHIESA DI SANTA MARIA DELLE GRAZIE A PETTINO (AQ)

The topics linked with the conservation, the sustainability and the resilience of historic centers are joined by the same targets: the protection of the real estate and its improvement over time. These subject affect whether the areas of history and restoration and city planning or more strictly scientific and technological aspects. The historic centers and the single architectures, sometimes injured by the carelessness and sometimes damaged by natural events, are a complex issue due to the diversity of the matters involved in the choices of action. Although it is difficult to approach the study of the preexisting in the light of the different points of view, we analyze the issue, assessing the implications of the different disciplinary contributions. Therefore, the thesis is divided into three parts, presented below. In the first part, with reference to the Italian territory, the evolutionary history of the cities at various times has been briefly traced, so as to delineate the cultural context of the prestigious monuments we have inherited from the past and which is often the subject of structural and not-structural works, necessary for the heritage survival. The path taken seeks, above all, to identify the characteristics of the urban environment and the specific aspects of each era, in order to understand the unique value of each context and redesign, if necessary, the condition of the places, with a point of view of sustainability and for increasing the resilience of the built environment. At the same time, concepts created in the restoration have been followed, spanning positions often conflicting and suggesting open questions. After a brief analysis of the considerations made in the decades by scholars belonging different disciplines, the new trends in the restoration have been outlined, that relate the conservation of historic centers with the growing demand of sustainability as well as the needs of resilience. The second part deals with the issue, instead, of seismic risk, now considered one of the most devastating threats for the safety of the urban habitat. The study inevitably covers the topics of hazard, vulnerability and exposure for the risk assessment, focusing mainly on the vulnerability of the built environment and on the methodologies used for its determination. In the same section has been then explored the theme of the masonry structures, which are the most recurrent type of construction in city centers and in old buildings. The different kind of damage have been presented in detail, which are typical for these monuments and the tools that may facilitate the study of urban aggregates and those related to the single buildings, considering the codes for masonry buildings currently in use. The third part, concluding this work, proposes two case studies: the town of Arsita (Teramo), the Santa Maria delle Grazie Church in Pettino (L’Aquila), both damaged by the 2009 earthquake. The first case, thanks to the Reconstruction Town Plan, recently worked out by ENEA (National Agency for New Technologies, Energy and Sustainable Economic Development), in collaboration with the University of Naples “Federico II”, the University of Chieti - Pescara “Gabriele D’Annunzio” and the University of Ferrara, outlines a new intervention strategy, dealing with the emerging ideological trends, applicable for the preservation of the built environment and the promotion of local development. In the second case, instead, the damage, suffered by the church, were analyzed in detail. The two examples show how the same objectives can be pursued at different scale, from the urban dimension to the architectonic space, and they demonstrate how the research may foster new ideas about the conservation of historic centers and practical models to imitate in similar situations.