From delay to disruption: The impact of service degradation on public transport networks

Abstract

Public transport networks (PTN) are affected daily by different types of disturbances. In fact, between a single delay and a long service interruption, there is a range of disruptions with different impacts, dependent by their characteristics. Despite this, in literature the common definition of disruption is a link closure for a certain amount of time. Low interest is given to different types of disruptions or to the connection between delays and disruptions. In addition, in multimodal PTN a link closure is not always observable, but rather people experience delays or cancelled stops on different lines. The aim of this work is to explore the relationship between delays and disruptions, analyzing different degrees of disruptions, in terms of duration, delay, size and network characteristics. Real disturbances of the Zürich and Bern PTNs are analyzed to identify disruptions with different characteristics. Hence, the disruption impact is computed on simulated ODs, based on the sets of possible paths with and without the disruption. For this purpose, a choice set generation algorithm is proposed. Finally, relationships between the disruption characteristics and the impact are analyzed to identify the main features of a disruption.