The research proposes an innovative, multidisciplinary, and multiscale methodology for analyzing historical centres, aimed at improving their resilience and reducing their vulnerability against seismic actions.
The Italian territory has a large amount of historical town centres, collecting most of national built heritage, monuments and minor architecture, having a considerable cultural, social and economic value. Most of these centres are vulnerable to seismic actions and periodic catastrophic events demonstrated the need for effective and efficient strategies for their preservation and resilience.
However, the damage caused by a seismic event is not only due to singular building collapses, but also by their consequences on the surrounding complex built environment typical of historical town centres. Therefore, vulnerability analyses need to be extended from The proposed methodology will be particularly addressed to the Minimum Urban Structure (MUS) of the historical centre, made of strategic buildings, roads, networks, spaces, which must remain functional during and after a seismic event, allowing to manage the emergency and drive reconstruction plans. The research is based on an extensive analysis of the centre that allows to create an accurate numerical model able to predict damage scenarios and preparatory to the design of an in-time Structural Health Monitoring (SHM) framework of the MUS.
The methodology promotes an extensive and detailed analysis of the historical centre. Surveying activities focus on buildings and urban context geometry, materials, construction techniques, also accounting for their evolution throughout time, taking into account seismic history of the context, and paying attention to historical masonry material and to pre-modern anti-seismic devices. The urban context is also analyzed, in order to find or define the MUS of the centre.
A fast seismic vulnerability analysis at urban scale is initially envisaged for qualitatively highlighting the weaknesses of the centre and evaluating potential damage scenarios. Then, the core of the project is the development of a multi-scale numerical model for accurately evaluating the seismic vulnerability of certain buildings interfering with the MUS and also highlighted as critical by the damage scenarios. Strategic buildings, together with building aggregates and row buildings close to emergency spaces and paths, are modelled in a multiscale manner (material, structural detail, structural element, single building, multiple buildings) thanks to the information collected by preliminary analyses.
A SHM framework, introduced for calibrating the numerical model, is finally designed to continuously monitor the evolution of vulnerability at urban scale of the centre. Such a tool will allow Civil Protection authorities, especially in case of long seismic sequences, to better manage emergency plans, first-aid interventions, rescue operations.