Assessment of Urban Spaces Based on the Principles of Passive Defense; Case Study of Enghelab Square Area, Tehran, Iran

Aims: Reducing the city's vulnerability in times of crisis and emergencies is part of the urban design mission. Hence, passive defense measures have been developed to reduce the vulnerability of cities in times of crisis. The purpose of this study was to identify the factors affecting passive defense in the performance of urban spaces in the area of Enghelab Square in Tehran. Methodology: This research was based on an evidence-based design method in the area of Enghelab Square in Tehran in 2020. So, first case samples and previous research were reviewed and then vulnerability indicators were extracted. Then, these indicators were weighed against each other using the AHP method and using the opinions of experts in the field of urban planning, urban management, and passive defense, and the importance of each to the other was determined. The weight of each element was applied in the relevant layers in the spatial system and with GIS 10.8 software, vulnerability zoning was performed for each of the main indicators. Findings: In the Enqelab square area, the indicators of vulnerability were: vital arteries (water, electricity, gas, telecommunications, and fuel station), physical structure (building density, texture, and width of passages), relief centers (hospital and fire department), access network, and Transportation (metro, bus, and traffic volume), at-risk population (population density), concentration of activities (educational and cultural, commercial-administrative, cinema, mosque, and church), and political-security centers (military centers, judiciary centers, Embassy, and Justice) In the vulnerability assessment matrix of the study area, it was determined that injuries such as fire, difficulty in providing assistance in times of crisis and traffic problems in all of these indicators, and finally, the final vulnerability map of the area was obtained. Conclusion: Based on the considerations and principles of passive defense, the vulnerability of the study area increases in a crisis situation.