Three-dimensional analysis of a damaged masonry arch bridge under horizontal load

The aim of this paper is to study the vulnerability to horizontal loads of a severely damaged masonry arch bridge located in the province of Ascoli Piceno (Marche, Italy). The bridge is a traditional single-span masonry arch designated as road bridge. A wide fracture line has been observed along the longitudinal direction. The arch has been studied by applying two distribution of horizontal loads directed in the longitudinal and the transversal directions separately. A new upper bound limit analysis recently developed by the cooperation of the Polytechnic University of Milan and the University of Ferrara has been adopted. For the case of horizontal load acting along the longitudinal direction, the capacity curve and the associated fragility curve are presented.