SEISMIC DAMAGE SIMULATION AND LOSS ESTIMATION IN URBAN AREAS
Hamed Esmaeili
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Abstract
I. ABSTRACT Seismic damage simulation and loss estimation is a very important task for the civil protection departments and urban planning policies for earthquake hazard mitigation. Many different software packages have been produced around the world in order to provide accurate loss estimates. Building damage functions for ground shaking include: (1) fragility curves that describe the probability of reaching or exceeding different states of damage given peak building response, and (2) building capacity (pushover) curves that are used (with damping-modified demand spectra) to determine peak building response. For use in lifeline damage evaluation, a separate set of building fragility curves expresses the probability of structural damage in terms of peak ground acceleration (PGA). Damage is described by one of four
Figures (4)
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Bulletin of Earthquake Engineering, 2004
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Italian territory is particularly sensitive to seismic actions. The Amatrice earthquake on August 24th 2016 confirmed this aspect. Such an event, nothing but extraordinary, has been able to cause huge and tragic damages. The direct knowledge of building features is the only prior measure to face seismic events. In order to get a realistic scenario of the urban damage distribution, the determination of useful seismic vulnerability assessment tools at urban scale becomes a priority. The widespread application of seismic vulnerability assessment sheets and the related data transformation into urban damage distribution plans is exactly what municipalities need. Main advantages are both in the chance of prior knowing the most affected areas to focus on for retrofitting interventions and in the possibility of organizing optimal emergency plans. In European framework, in the last decade, the Risk-UE project has played an important role. The Risk-UE project has proposed two methods for vuln...
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International Journal of Disaster Risk Reduction, 2015
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This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/copyright Abstract Conceptual aspects related to seismic vulnerability, damage and risk evaluation are discussed first, together with a short review of the most widely used possibilities for seismic evaluation of structures. The capacity spectrum method and the way of obtaining seismic damage scenarios for urban areas starting from capacity and fragility curves are then discussed. The determination of capacity curves for buildings using non-linear structural analysis tools is then explained, together with a simplified expeditious procedure allowing the development of fragility curves. The seismic risk of the buildings of Barcelona, Spain, is analyzed in the paper, based on the application of the capacity spectrum method. The seismic hazard in the area of the city is described by means of the reduced 5% damped elastic response spectrum. The information on the buildings was obtained by collecting, arranging, improving and completing a broad database of the dwellings and current buildings. The buildings existing in Barcelona are mainly of two types: unreinforced masonry structures and reinforced concrete buildings with waffled-slab floors. The ArcView software was used to create a GIS tool for managing the collected information in order to develop seismic risk scenarios. This study shows that the vulnerability of the buildings is significant in Barcelona and, therefore, in spite of the low-to-moderate seismic hazard in the region, the expected seismic risk is considerable.
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