Repair Strategies for Failure of Urban Rail Transit Stations

In order to improve the ability of urban rail transit (URT) systems to respond to emergencies, the effective repair strategies for URT stations under natural disasters and human attack are discussed. Firstly, the station failure caused by natural disasters and human attack are simulated by random attack and intentional attack, respectively. Secondly, the simulation repair strategy for damaged URT network is proposed. Finally, the average repair strategy, preference repair strategy and simulation repair strategy are used to repair the damaged URT network, and the effectiveness of repair strategies is measured with two categories of resiliency loss indicators: global accessibility resiliency loss and global proportion of unaffected passengers resiliency loss, which are proposed on the basis of the global accessibility and proportion of unaffected passengers. The results show that the global accessibility and proportion of unaffected passengers decrease by 2.54% and 64.82% in case of intentional attack, which are higher than 2.34% and 55.28% of random attack. Intentional attack is more harmful to the URT network than random attack. When the damaged URT network caused by random attack is repaired, the resiliency loss indicators of the simulation repair strategy are 0.009 and 0.182, which are better than 0.012 and 0.305 for average repair strategy and 0.010 and 0.197 for preference repair strategy; when the damaged URT network caused by intentional attack is repaired, the resiliency loss indicators of the simulation repair strategy are 0.009 and 0.258, which are better than 0.012 and 0.312 for average repair strategy and 0.014 and 0.354 for preference repair strategy. It indicates that the simulation repair strategy is more suitable for repairing the damaged URT network. The average slope of the simulation repair strategy curve is 0.146, which are higher than 0.092 for average repair strategy and 0.117 for preference repair strategy. Compared with conventional repair strategies, the simulation repair strategy has higher repair efficiency. Using simulation repair strategy can achieve optimal result when the repair resources are limited.