Joint bus dispatching and bus bridging timetabling for mass rapid transit disruption management

The mass rapid transit (MRT) systems play a pivotal role in urban mobility services but are frequently susceptible to various disruptions. Bus bridging service is a widely-applied substitute transit service in response to MRT disruptions, which requires a significant number of buses to transport stranded MRT passengers. In practical applications, these buses may be dispatched from the nearby bus lines or bus depots, which inevitably affect bus passengers. However, the literature has paid very little attention to the sources of buses and impractically assumed buses are immediately available. To bridge this gap, this paper proposes a joint optimization problem integrating bus dispatching and bus bridging timetabling, considering the balance between the impact of bus dispatching on bus passengers and evacuation of MRT passengers. A mixed integer linear programming model is developed to minimize total penalties caused by affected onboard passengers and cumulative waiting passengers in both bus and bus bridging systems. A tailored decomposition method is devised to find high-quality solutions efficiently. By applying the decomposition method, the model is split into three sub-problems, which are solved by three tailored and efficient methods developed based on their unique features. The efficiency of the proposed method is demonstrated using Singapore case studies. The computational results show that our method can guide bus dispatching efficiently to evacuate stranded passengers while minimizing the impact on bus passengers. Finally, the impacts of duration, bus frequency, passenger demand, and penalty coefficients are analyzed.