Spatial accessibility measurement of urban fire stations considering multi-path characteristic of road networks

Abstract

Given the travel time variability and potential disruptions in urban road networks, fire and rescue services may encounter unexpected response delays or even inaccessibility despite having the highest road privilege. This paper develops a multi-path accessibility measurement model tailored for fire stations (FSs). This model assesses the resilience of road networks surrounding fire and rescue systems by considering both the timely response requirement of fire and rescue services and the unique characteristics of multiple paths within road networks. The proposed model incorporates the availability of multiple road paths for fire vehicles as a strategic approach during the ex-ante stage to proactively address uncertainties inherent in road networks. By operating across three distinct levels, this model provides a comprehensive multi-path accessibility measurement of fire and rescue services in terms of their effectiveness at fire station - fire demand point (FS-FDP) pairs, spatial equity among FDPs, and resilience of FSs in navigating the challenges posed by uncertainties in road networks. The proposed model is applied to a realistic case study in Xuhui, Shanghai. Results indicate significant differences in the multi-path accessibility across three distinct levels, demonstrating the spatial inequity and disparity in the resilience of road networks surrounding fire and rescue systems. Meanwhile, we observe that the multi-path accessibility is greatly affected by road network density and travel time reliability. The proposed model can help identify the factors contributing to insufficient accessibility of fire and rescue services from the perspective of urban road network conditions, supplementing traditional accessibility measures to prevent misguided investments in fire and rescue facilities and guide the urban fire system planning.