Abstract

In this article, the fragility of reinforced concrete and steel structures in Bucharest, a city of high seismic hazard, designed using the recent building codes in Romania, is assessed. A total of 24 reinforced concrete and steel structures with heights varying from five stories to 13 stories were analyzed. Their seismic fragility was evaluated using two procedures from the literature. In the first procedure (SPO2FRAG), the fragility was derived based on the pushover curves using the SPO2IDA algorithm, while in the second procedure (FRACAS), the fragility was derived from nonlinear time-history analyses. The analyzed structures were designed for three levels of peak ground accelerations, corresponding to mean return periods of 100, 225, and 475 years. Subsequently, the damage assessment of the analyzed structures was performed using ground motions generated from a Monte-Carlo simulated earthquake catalogue for the Vrancea intermediate-depth seismic source. The damage degrees that were estimated using the SPO2FRAG approach are higher than those estimated using the FRACAS approach. The life-cycle analysis of the structures shows that a further increase of the design peak ground acceleration for Bucharest is feasible from an economic point of view using the SPO2FRAG results. However, based on the FRACAS results, the opposite conclusion can be drawn. Finally, generic lognormal fragility functions are proposed as a function of building height and structural system.

Highlights

  • Bucharest, the capital city of Romania, is one of the highest seismic risk cities in Europe because of its proximity to the active Vrancea intermediate-depth seismic source and due to a vulnerable building stock

  • We evaluate the seismic fragility of bisymmetrical reinforced concrete (RC) and steel structures in Bucharest that were designed for three levels of peak ground acceleration—0.24, 0.30, and 0.36 g

  • Bds IM;ds where IM;ds is the median value of the ground motion intensity measure at which the building reaches the threshold of damage state; bds is the standard deviation of the natural logarithm of the ground motion intensity parameter corresponding to damage state

Read more

Summary

Introduction

The capital city of Romania, is one of the highest seismic risk cities in Europe because of its proximity to the active Vrancea intermediate-depth seismic source and due to a vulnerable building stock. A seismic risk assessment of Bucharest’s residential building stock was conducted by Pavel et al (2017a). The HC typology consists of the buildings designed using the 1992 and 2006 versions of the Romanian seismic design code. The mean return period and the corresponding design peak ground acceleration (PGA) for Bucharest have increased from 50 years (PGA = 0.20 g) in the 1992 version of the code, to 100 years (PGA = 0.24 g) in the 2006 code, and to 225 years (PGA = 0.30 g) in the 2013 version of the seismic design code.

Methods
Results
Conclusion

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.