access enhancement by making changes in the route network to facilitate rescue perations in urban disasters

having access to locations struck by natural environmental disasters is one of the chief necessities in urban disaster management. this paper aims to study different physical and semi-physical patterns for increasing access to different districts in a city through applying changes to the present network of routes. to attain this goal, district 6 of tehran municipality was selected for the case study. the technique used in this research is based on multi-criteria decision- making methods. thus, the patterns and indices were extracted by means of ahp method, and then the indices were assigned weights. these patterns were, then, analyzed and ranked through topsis, fuzzy and saw techniques respectively. next, the results were combined by means of borda method. the results indicated that a4 pattern which obtained 7 maximum scores was the most efficient pattern in increasing access through changes in the network of routes. next to it is a3 pattern which ranked second. it is, therefore, suggested that in order to increase access for rescue operation in urban disasters, parallel routes in directions of the first and second priority, east to west and north to south, must be constructed so that arterial roads in the district offer better services in normal and emergency conditions.