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- Resumen es exacto "Recent earthquakes in countries with high level of seismic preparation have shown that the minimum requirements imposed in most building codes in force throughout the world may be insficient for satisfying the socio-economic needs of the afected regions. As a result of the increased awareness of the risks associated to large seismic events, researchers and practitioners have paid greater attention in recent years to the need of improving earthquake resilience of buildings and other infrastructure. From a structural engineering perspective, this implies that the design process should not focus only on minimizing collapse risks, but also on post-earthquake functionality or, at least, the ability of being repaired as quickly as possible after strong events. In other words, seismic resilience implies designing for higher performance than that provided by minimum code standards. The purpose of this thesis is to promote the introduction of such performance objectives in the design process of civil infrastructure, both in areas of high seismicity as in the City of Buenos Aires, Argentina, often considered a non-seismic zone. When the seismic hazard at the site of interest is high, the establishment of additional goals is hindered by the fact that verifying compliance requires performing a probabilistic performance assessment. Rigorously, this implies conducting hundreds of response history analyses with a sophisticated numerical model, a task that involves a computational efort that is not manageable in practical applications. For this reason, several studies have focused on developing approximate performance assessment procedures using only a limited number of analyses. This study presents a critical review of such approaches, discussing the theoretical framework and their limitations for evaluating performance objectives posed in probabilistic terms. Based on these observations, the thesis then introduces a novel performance assessment procedure, which stands on the idea that the earthquake records that should be used for evaluating a certain performance objective depend on the structure and, therefore, on its numerical model. The result is a procedure that relies on the use of models of diferent degree of complexity. It is referred to as a \demand-oriented assessment" in the sense that it aimed at estimating the level of demand associated to the allowable failure rate of the performance check of interest. The benficts of the proposed procedure are illustrated in the performance assessment of an archetype building representative of current engineering practice in areas of high seismicity. In Buenos Aires, unlike the aforementioned, the greatest challenge that must be overcome for implementing performance-based design concepts is the total absence of information related to the seismic hazard at the site. Earthquake hazards in Buenos Aires have been traditionally ignored until 2015, when the School of Engineering of the University of Buenos Aires installed the only working seismometer in the city. This study summarizes the information obtained from the first set of ground motions recorded in Buenos Aires to date. The analysis of these records shows the existence of signficant site effects, which make Buenos Aires particularly sensitive to distant earthquakes of great magnitude, such as those that occur in western Argentina and central Chile. Based on these observations, the thesis conducts a preliminary probabilistic seismic hazard analysis that considers both local and long-distance events. In order to achieve this, a set of site-specific ground motion prediction equations are developed considering the features of the soil deposit. Noting that these preliminary results suggest that the provisions of the Argentine building code could be insuficient, the study establishes recommendations for implementing performance-based approaches in Buenos Aires."
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