New methods and perspectives in bus bridging theory and practice

In a time of increasing road congestion, passenger rail networks provide superior performance to commuters in terms of capacity and speed. Although their technical complexity greatly assists in delivering these improved service levels, it also makes them vulnerable when unplanned disruptions occur. Such unexpected occurrences can be due to infrastructure malfunctions, accidents and extreme weather conditions. These incidents can often result in the rapid degradation of existing service levels given that the options for alternative internal solutions are limited. This is unlike the road network, where when one link fails, traffic can be diverted to neighbouring roads. Unfortunately, passenger railway networks are not as resilient and often a common solution to addressing disrupted commuters' travel needs is to provide alternative transportation modes such as buses. Bus bridging or the provision of buses to replace rail during service disruptions is a common response. This paper presents a synthesis of findings from a research program seeking to improve responses to unplanned passenger rail disruptions. Component parts of the research described, seek to understand current international practices, explore the significance of track crossovers to bus bridging, explore ways to optimise bus bridging depot location and the economic viability of a bus bridging reserve. Currently the management of unplanned service disruptions and the resultant initiation of bus bridging services are viewed reactively. This research paper demonstrates that it is possible to proactively plan for such incidents. Unplanned disruptions by their very nature are unexpected events; however, preparations can be made to minimise their impacts.