Earthquake-resistant design evaluation applying fragility curves

Abstract

The earthquake-resistant design codes use strength and capacity methodologies for the design of structures in terms of resistance. However, over the years performance methods have become noteworthy, as they make possible the design of structures with controllable behavior under defined levels of risk. The risk analysis considers three factors: threat, vulnerability and exposure; therefore, although Brazil is located in an intraplate region with earthquakes of medium or low magnitude, this effect cannot be underestimated, as the structural vulnerability can make the consequences of these earthquakes potentially high. Although the current Brazilian seismic standard is NBR 15421 (2006), recent studies indicate that the national seismic threat scenario is more intense than the considered in this code. Besides, the main international seismic codes are intensifying their dimensioning measures and including performance methods. Hence, this project aims evaluating and comparing earthquake-resistant designs based on strength and capacity methods with the methodology of performance due to seismic fragility. It will be take a typical Brazilian reinforced concrete structure under small, medium and high seismicity; and the design of the structure will be carried out by national and international codes. A performance analysis will be conducted establishing: the history-time of seismic events, the probabilistic seismic demand model and the capacity of the components. Finally, the results are going to being evaluated and compared regarding differences in performance and damage by type of design.