Evaluation of vulnerability rate of urban fabrics to earthquake using ANP and GIS techniques (Case study: Semirom city)

Planning with the aim of crisis management and earthquake risk estimation has always been one of the main concerns of urban planners and managers. In order to plan crisis management before the occurrence of earthquake, determining the vulnerability rate of urban fabrics to earthquake is necessary. This research was aimedat providing an appropriate model for assessing the vulnerability of urban fabrics of Semirom city,located in Isfahan province, to earthquake. The current research is descriptive-analytical in nature with practical aims. To begin with, the criteria affectingthe vulnerability of urban fabrics to earthquake were identified, and then the value and importance of each criterion were determined by using Analytic Network Process. Finally, the results obtained from Analytic Network Processwere integrated with main and side roads, population density, buildingsquality, land slope, distance from fault, green space, health centers, cultural centers, and educational and residential centers, and vulnerability map of Semirom urban fabrics to earthquake was prepared. The results showed that among the studied criteria, population density, side road and distance from the fault were the most important criteria, while distance from cultural and educational centers had the least importance in vulnerability of urban fabrics. Furthermore, vulnerability of the northern and central parts of the city was higher than other areas of the city due to their proximity to the fault line and the presence of old buildings in these parts. Based on the results obtained from digital layer of urban fabrics of Semirom city, losses and damages caused by the earthquake can be significantly reduced by proper planning before and after the occurrence of earthquake. It should also be noted that tectonic aspect is one of the factors that has always been neglected throughout the history; therefore paying attention to slope issue and other factors in urbanism has had evolutionary process.