Transportation Accessibility to Health Services Based On Earthquake Micro Zoning Study of Ray Fault Model Scenario: A Case Study of Central Restricted Zone in Tehran Municipality

In this paper, defining a probable earthquake, a calculating measure as transportation accessibility level was presented. After data collecting include: road network, population, building, seismic risk, hospitals; an appropriate network for analysis based on GIS environment was prepared. By determining centroids of each district (totally 32) zone as an origin was selected and the health service center (totally 45) as a destination was determined. Travel speed (in the of range 5km/h - 20km/h) was assumed. Road blockage caused by collapsed building was simulated with point barrier, line barrier and polygon barrier in GIS environment. According the result of network analysis in periods (10, 15, 30, 45 minutes) access to any health service and changing the accessibility by time has been shown. The analysis was performed with blockage condition; the results showed that the accessibility index significantly dropped but the changing index with barriers was similar to without barriers. Moreover, the change rate of entire index in the network without blockage comparing network with blockages links is more sever.