Modeling and Zoning the Earthquake Risk Using Fuzzy TOPSIS Model (Case Study: Kermanshah City)

The earthquake is one of the most important environmental hazards in many Iranian cities. In this regard, spatial assessment and micro-zoning of seismic vulnerability of cities are essential requirements in earthquake mitigation planning. In the present study, seismic vulnerability of Kermanshah metropolis is investigated. Crossing three important fault lines in the vicinity of Kermanshah city has caused earthquake hazard in this urban area. One of the main measures to reduce the vulnerability of Kermanshah city to earthquake risk is seismic assessment and zoning of the city in order to implement earthquake mitigation plans. In this context, 11 variables affecting the seismic vulnerability of the city were used. These variables are: fault distance, slope, lithology, population density, land use, residential density, and major communication networks, access to hospitals, operating radius of fire stations, and distance from hazardous facilities, and access to urban open spaces. Fuzzy TOPSIS technique was used to combine these variables in the context of GIS. The results show that about 32% of the area of Kermanshah is in a very high vulnerability class. Neighborhoods located in the central part of the city (the core of the city) are among the most vulnerable to earthquake hazards in Kermanshah. In this context, factors such as proximity to faults in the southern margin of the city, high population density, high residential density, marginalization, the presence of worn urban texture, and the lack or severe shortage of open urban spaces are among the most important causes of high vulnerability of these neighborhoods.