Historical Development and Seismic Performance of Unreinforced Masonry Buildings with Vertical Extensions in the City Centre of Barcelona

This paper presents the historical development of the vertical extensions of unreinforced masonry buildings in the Eixample district of Barcelona and their impact on the seismic behaviour. Existing masonry buildings of Eixample present significant seismic risk because, despite the low to moderate seismic hazard of Barcelona, they show a marked vulnerability given their average height of six storeys and the substantial slenderness of the walls. Between the end of the 19(th) century and the beginning of the 20(th) century, the vertical extensions, known as remuntes in Catalan, were a common solution to the increasing demographic demand of the city. In their majority, these vertical extensions add a structural irregularity that represents a potential vulnerability factor not yet investigated. The present study focuses on Eixample's remuntes, including their historical development, the description of their structural features, and the identification of their most representative configurations in the existing building stock. A seismic analysis based on the Finite Element Method is presented on a reference model without extensions and three others with the most recurrent configurations of remuntes. The seismic response is investigated through pushover analysis. The results provide a better understanding of the negative impact of the vertical extensions on the seismic performance.

Automated summary

This paper presents the historical development of vertical extensions in unreinforced masonry buildings in the Eixample district of Barcelona and their impact on seismic behavior. The study found that despite the low to moderate seismic hazard of Barcelona, the existing masonry buildings in Eixample pose significant seismic risk due to their average height and slender walls. Vertical extensions were a common solution to meet the increasing population demand, but they add structural irregularities that negatively affect seismic performance.