Print Email Facebook Twitter Capacity drop: Relationship between speed in congestion and the queue discharge rate Title Capacity drop: Relationship between speed in congestion and the queue discharge rate Author Yuan, K. (TU Delft Transport and Planning) Knoop, V.L. (TU Delft Transport and Planning) Hoogendoorn, S.P. (TU Delft Transport and Planning) Date 2015 Abstract It has been empirically observed for years that the queue discharge rate is lower than the prequeue capacity. This difference is called the capacity drop. The magnitude of capacity drop varies over a wide range, depending on the local traffic conditions. However, it is unknown what determines the capacity drop value. No thorough empirical analysis has yet revealed a reliable relationship between the capacity drop and the congestion level. This paper fills the gap by revealing, through empirical analysis, the relationship between vehicle speed in congestion and the queue discharge rate. The research studies congested states in which speed ranges from 6 to 60 km/h. The queue discharge rate is shown to increase considerably with increasing speed in the congestion. In contrast to previous research, this study bases the relationship on empirical data collected on freeways, and the data present a sufficiently large observation sample. A discussion about the influence of weather and study site characteristics on the discharge rate indicates that the relationship needs site-specific calibrations. This study provides a better prediction of capacity drop and a better theoretical understanding of the fluctuations in capacity drop. Subject CWTS JFIS < 0.75 To reference this document use: http://resolver.tudelft.nl/uuid:0092358c-7972-4191-8c12-45758b143c58 DOI https://doi.org/10.3141/2491-08 Embargo date 2015-07-01 ISSN 0361-1981 Source Transportation Research Record, 2491, 72-80 Bibliographical note Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public. Part of collection Institutional Repository Document type journal article Rights © 2015 K. Yuan, V.L. Knoop, S.P. Hoogendoorn Files PDF 2491_08.pdf 2.15 MB Close viewer /islandora/object/uuid:0092358c-7972-4191-8c12-45758b143c58/datastream/OBJ/view