Analysis on effective components in reducing the vulnerability of informal settlements against earthquakes Case study: Farahzad neighborhood Tehran Metropolitan Area 2

Urban settlements have become more complex, and, consequently, instability has increased in these settlements. In this regard, the urban community, especially in its contemporary and modern forms, has been exposed constantly to a wide variety of threats. Much of the damage caused by these hazards, more than the result of unexpected events, is a predictable result of the interaction of three major systems: the physical environment (including hazards), social and demographic characteristics, and moreover the mechanism is the management and planning system. Therefore, the purpose of this study was to investigate the vulnerability of Farahzad neighborhood and identify the effective factors on it. Farahzad neighborhood due to the non-chemical and erosive texture and the location near the Laser land fault in the event of an earthquake, the damage caused by it will be doubled.

In this regard, the present study uses a descriptive-analytical method and has developed a comprehensive index and application of the AHP model in ArcGIS environment to analyze the vulnerability of Farahzad neighborhood. Also, the questionnaire was distributed among the residents of the neighborhood. The sample size is selected using the Cochran formula according to the neighborhood population. Thus, according to the population of 5931, 357 people have been selected as the sample size. Pearson and regression tests were used to analyze the questionnaire.

The findings show that the quality of the building is the most important factor in reducing vulnerability to possible earthquakes. It was also found that Farahzad neighborhood is not in desirable position as a vulnerability, with 28% having high vulnerability and 13% high vulnerability. Finally, for analyzing the effective components of vulnerability reduction, the questionnaire was evaluated and analyzed by Pearson test and multivariate regression. The results of the test analysis indicate that the physical-environmental index in the first place, and then the institutional-management index, are an effective factor in reducing vulnerability.

The existence of major weaknesses in the physical structure of the neighborhood, especially its passageways, has caused the region to be more vulnerable to crises during the crisis. In terms of institutional management, this neighborhood also has a lot of challenges. The necessity of paying attention to the crisis management agent is related to the management factors, so that the implementation of educational maneuvers and monitoring of construction can reduce the vulnerability of the neighborhood seriously.