• About the project
• Objective
• Summary
• Implementation plan
• Results
• Tasks
  • Phase 1
  • Phase 2
  • Phase 3
  • Phase 4
  • Phase 5
• Publications

Phase 3 / 2014 (01.2014-12.2014)

Urban vulnerabilities analysis

Summary

The phase objective refers to urban vulnerability assessments in different seismic risk scenarios. Vulnerability is the potentiality of an element at risk to suffer damage following an earthquake. The vulnerability is the most important factor in mitigate disasters and knowledge about the vulnerability of an urban space - regardless of the scale of analysis: city, district or building - is premise of minimizing the risk. At this stage of the project, due to the drastic reduction of funds allocated to research in 2014, the objectives were limited to assessing the physical and the socio-economic vulnerabilities. These objectives were fully achieved, based on census data from 1992, 2002 and 2012 and by field analysis carried out in the city center.

The innovative aspects brought by the 2014 phase of the project refer to the multi-criteria applications deployed in the spatial analysis of the physical vulnerability by analytical methods. The analytical method used in this project to estimate the probability of buildings being affected was the Improved Displacement-Coefficient Method (I-DCM). This was chosen because of the good results previously demonstrated in the application for Bucharest (Thomas-Danila et al., 2014) and also because it is an up-to-date method, internationally appreciated (Lang et al., 2012) and used in the real-time Assessment System of damage caused by an earthquake in Romania, by the National Institute for Earth Physics.

In order to analyze the seismic risk based on the I-DCM method, the open-source software SELENA (Seismic Loss Estimation using a logic tree approach) was used. This software was developed by the Institute Norsar from Norway. The input data was the March 4, 1977's earthquake scenarios, based on real recordings, and the vulnerability data for buildings from 2011-2012 and the 1999 censuses.

The result shows that the highest percentage of damaged buildings could be not so much in the center of Bucharest (although percentages are significant here too), but in areas closer to the periphery, with a building profile characterized by a greater number of low-rise buildings. We could expect damages very close to those in the past (which is quite credible, judging by the fact that over 373 of individual buildings expertised from a total of 2563 old buildings are already classified as class I of seismic risk - PMB, 2014). The fact shows that although certain measures were taken to reduce the risk, reflected in the design of new buildings, housing remains vulnerable and aged. 

The second major objective focused on the analysis of socio-demographic and economic vulnerability in terms of historical and current census data.

Bucharest's urban space transformations registered after 1989 show a continuous deepening of directions already started after the Revolution. The situation of censuses carried out starting with 1992 marks the change of many social issues that led to the development of a dynamic social profile. The indicators used to capture the testing of population, based on the latest census, followed the socio- demographic and housing indicators, according to the methodology described in Armas and Gavris, 2013. As a general conclusion remains the state of degradation of most of the housing inhabited by population still concentrated in large housing estates, with a tendency to increase social discrepancies.