21474

21474

تدوين مدل مفهومي و راهبرد استوار افزايش برگشت‌پذيري مناطق شهري با تأكيد بر زلزله مطالعه موردي شهرداري منطقه 6 شهر تهران

دكتري

شهرسازي

1391

1398/8/30

دكتر مصطفي بهزاد فر

دكتر محمد باقر قاليباف

معماري و شهرسازي

1398/09/24

تدوين مدل مفهومي و راهبرد استوار افزايش برگشت‌پذيري مناطق شهري با تأكيد بر زلزله مطالعه موردي شهرداري منطقه 6 شهر تهران

12/15/2019 12:00:00 AM

Disasters have always had a negative impact on human life. Individuals and communities try to reduce exposure to these disasters and their consequences and to develop scales for assessing their primary impacts. The study of cities resilience against earthquake is one of the planning requirements of earthquake mitigation in cities. Resilience has many definitions and there is no comprehensive model to quantify it. In this research, using library studies and expert opinions, the dimensions that influence the urban resilience against earthquake are identified. The economic, social, technical, physical, security, and institutional dimensions are considered to be the major urban earthquake resilience having their own indicators. Next, the relative weights of these dimensions and indices were obtained by pairwise comparison using 20 expert opinions. Accordingly, the physical, social, security, economic, institutional and technical were ranked in order of high to low importance, respectively. Combined index of urban resilience is presented using the results. In the next step, considering the district No. 6 of Tehran as the study area, information on each of the indicators and dimensions was extracted and three seismic scenarios were selected from JICA report to investigate the resilience status of the area and improvement strategies. Strategies, including "structural-engineering" (technical and physical), "human-social" (social and economic), and "governmental" (institutional and security), and a combination of them were introduced. They were given three levels of 10, 50, and 90 percent improvement, and eventually 21 strategies were considered. Using expert opinion to compare strategies, the implementation time and cost was considered. Then their regrets were calculated based on the resilience values. Three measures were considered to compare strategies. At first, the rates of regret reduction were compared with each other. Then, the Pareto curve with least squares was used in the plot of time or cost versus regret and finally the ratio of regret reduction to cost was used. The regret values for the situation in the three seismic scenarios of North Tehran, Ray and Floatinf fault are 0.542, 0.546 and 0.544, respectively. The results for the North Tehran fault seismic scenario show that the best strategy in terms of resilience index is a 90% improvement in the "security - (economic - social) strategy", but the strategy has reduced the regret index by 11% compared to the 50% improvement and 23% more than the 10% improvement. Among the three groups of strategies, the highest impact was related to the human and social strategy and the least to the governmental strategy. In all the scenarios, the most cost-effective strategy is the S3 strategy (90% socio-economic improvement) and the most time-optimized strategy is the T1 strategy (10% technical-physical improvement). Choosing a robust strategy depends heavily on decision-limiting variables. However, in the short term T1 strategy and in the long term S2 strategy (50% socio-economic improvement) are the most optimal strategies.