Drift-based fragility assessment of confined masonry walls in seismic zones

The paper presents drift-based fragility curves developed for confined masonry (CM) walls, which are the main structural components for the lateral load-resisting systems employed in housing dwellings in Latin-America. Drift-based fragility curves were developed for two key damage states associated with the structural performance and repairability of CM walls, from experimental results of 118 confined masonry specimens tested under lateral cyclic loading, during research programs carried out in Mexico, Chile, Peru, Venezuela and Colombia. In particular, four sources of uncertainty, due to specimen-to-specimen, finite-sample, measured diagonal compression strength of the masonry and wall height-to-length aspect ratio were included. These fragility curves are very useful for assessing the seismic vulnerability of CM structures, and for estimating the earthquake-induced economic losses employing recently proposed methodologies based on aggregating the estimated damage at the component level for a specific structure.