Sparse rail network robustness analysis: Functional vulnerability levels of accidents resulting from human errors

Abstract

Transportation network vulnerability analysis has developed increasingly in the last decade with the goal to identify the most critical locations against incidences. In this domain, many of the previous researches have focused on congested urban networks; however, there is still a need to consider regional and interurban sparse rail networks, specifically those networks in developing countries. In such sparse rail networks, there are limited possibilities to redirect trains if a link is disrupted, there might be less possibility of finding redundant alternative routes, and network failures are usually accompanied by a phenomenon called ‘unsatisfied demand.’ The study reported in this paper stemmed from research aimed to design precautionary actions for a developing country's sparse railway system. Our study framework deemed to find the most vulnerable part of an inter-urban sparse rail network using a network scan approach, which found the consequences of network disruptions. A number of criteria were defined to determine the total cost including unsatisfied demand and additional transportation costs due to disruptions. The results showed that how well the process of the vulnerability analysis, considering the features of both supply and demand sides, can be a guide for railway authorities in applying system safety measures.