Seismic vulnerability and old towns. a cost-based programming model

Abstract

Seismic vulnerability affects particularly the small inland towns due to its multifaceted nature, concerning the social capital of city in its two main dimensions, the urban capital and the human capital. In some Italian regions, as well as in Emilia Romagna, municipalities are implementing seismic vulnerability reduction policies based on the Emergency Limit Condition, which has become one of the references for ordinary land planning. With reference to the general planning framework of the Faentina Union—a group of five municipalities in the southwestern part of the Province of Ravenna, Italy—this study proposes a cost-based valuation programming approach to the seismic vulnerability reduction for the old town of Brisighella. This approach involves three cognitive areas: knowledge, aimed at the typological, constructive, and technological description of the buildings, specifically concerning their seismic vulnerability; interpretation, as a critical analysis of the urban fabric representation aimed at outlining a range of earthquake damage scenarios; planning, as a generative pattern of multiple vulnerability reduction strategies having comparable costs, and in correspondence of different budgets. This pattern includes a cost modelling tool aimed at defining the trade-off between the extension and the intensity of the vulnerability reduction works, given the budget.