Overstress analysis of the Cartagena de Indias walls under different scenarios of masonry mechanical strength

Abstract

The historical city centre of the Colombian City Cartagena de Indias and its defensive walls have been classified as UNESCO cultural heritage since 1984. The structure is composed of an internal and an external masonry layer, divided by an embankment. The wall’s structural behaviour under static and seismic loads is currently unknown.The authors in a previous research (Saba et al., 2019a) identified a possible limestone masonry mechanical-parameter range (PR) through non-destructive tests. On the other hand, regarding historical structures the Italian Standard Circolare NTC, 2019 (for its Italian initials) proposes a limestone masonry mechanical parameter range for existing buildings.In the present study, the two previously identified ranges (PR and NTC) were compared. Additionally, these intervals were discretized in middle scenarios in order to study the wall’s structural overstress under different mechanical-parameter scenarios. The yield stress range was analysed on a typical external-wall section, and on two different internal wall configurations (deformed and undeformed).Under static load combinations, the walls responded adequately in all cases. However, under the seismic combination, the internal wall showed deficiencies with possible collapse, highlighting a higher seismic vulnerability on the deformed configuration. Finally, a statistical analysis was proposed showing a structure response equivalence in terms of overstress between PR and NTC scenarios. This demonstrates that the NTC Standard, designed for existing Italian masonry, can also be considered suitable for calcareous-rock masonry structures located in other parts of the world, such as the case of Cartagena de Indias walls.

Keywords

• Defensive walls behaviour
• Preliminary research for structure reinforcement
• Masonry stability