Railway disruption management: Designing bus bridging services under uncertainty

Abstract

In this paper, we study the rail transit disruption recovery problem under uncertainty, considering features of public transit network and commuters’ behavior in disruption. To be specific, our work highlights that spare capacities of operating rail and bus lines can provide complementary services to disrupted commuters and should be taken into consideration in disruption recovery plan. To this end, an integrated network is constructed, which consists of remaining available rail lines, existing operating bus lines and newly introduced bridging bus lines. Based on this network, alternative traveling routes for disrupted commuters are generated from a multimodal k-shortest path model. The model captures the fact that commuters can have several alternative routes in practice. They usually select one from them rather than insist on the shortest path. In addition, commuters may transfer between different lines when rerouting their travel. Based on the outputs of the aforementioned models, a stochastic programming model is developed for the design of bus bridging services plan within bus resource limit. The objective of the model is to minimize the expected unsatisfied commuter demand under rail transit disruptions, considering uncertainties in commuter demand and spare capacities of existing rail and bus lines. The proposed models are demonstrated on the core part of the Singapore Mass Rapid Transit network.