Seismic vulnerability assessment of existing masonry buildings by nonlinear static analyses and fragility curves

The seismic evaluation of existing masonry buildings is a fundamental subject matter in order to define prevention strategies and to reduce seismic risk. Multiple factors can affect the structural safety of each single building and their effects can be defined through the adoption of different analysis methodologies. One of these is the nonlinear static analysis of global behaviour: together with kinematic analysis, global analysis is one of the essential methods to be taken into account in order to obtain a comprehensive assessment on the seismic behaviour of existing masonry buildings. Through a knowledge phase conducted which included the collection of available historical documentation and in situ survey, nonlinear static analysis allows to correctly evaluation global seismic vulnerability. From these observations, an evaluate model has been defined for the assessment of the distribution of damage probability depending on the expected seismic activity starting from the capacity curves of each single building. The aim of this proposed procedure is to define fragility curves for each construction typology; the method is carried out analysing some representative historical buildings belonging to the architectural heritage of the University of Padova. The study adopted is based on a preliminary knowledge phase. The information collected to define the construction typologies regard parameters about geometrical and structural characteristics: urban settlements (building isolated or in the aggregate), number of stories, masonry thickness, typologies of horizontal structures and roofing. The structural masonry is composed of solid brick for all constructions. The analysis of the results will permit the application of the global vulnerability evaluation to other existing masonry buildings for different structures and on the basis of same construction typologies.