Print Email Facebook Twitter Mainstream traffic flow control at sags Title Mainstream traffic flow control at sags Author Goni Ros, B. (TU Delft Transport and Planning) Knoop, V.L. (TU Delft Transport and Planning) van Arem, B. (TU Delft Transport and Planning) Hoogendoorn, S.P. (TU Delft Transport and Planning) Date 2019 Abstract Sags are freeway sections along which the gradient changes significantly from downward to upward. The capacity of sags is considerably lower than the capacity of normal sections. Consequently, sags are often freeway bottlenecks. Recently, several control measures have been proposed to improve traffic flow efficiency at sags. Those measures generally aim to increase the capacity of the bottleneck, to prevent traffic flow perturbations in nearly saturated conditions, or both. This paper presents an alternative type of measure based on the concept of mainstream traffic flow control. The proposed control measure regulates traffic density at the bottleneck area to keep it below the critical density and hence prevent traffic from breaking down while maximizing outflow. Density is regulated by means of a variable speed limit section that regulates the inflow to the bottleneck. Speed limits are selected on the basis of a feedback control law. The authors evaluate the effectiveness of the proposed control strategy by means of a simple case study by using microscopic traffic simulation. The results show a significant increase in bottleneck outflow, particularly during periods of high demand, which leads to a considerable decrease in total delay. This finding suggests that mainstream traffic flow control strategies that use variable speed limits have the potential to improve substantially the performance of freeway networks containing sags. Subject Conf.proc. > 3 pag To reference this document use: http://resolver.tudelft.nl/uuid:0ae39528-2cb6-463a-b757-581c541715e9 DOI https://doi.org/10.3141/2470-06 Embargo date 2019-09-05 ISSN 0361-1981 Source Transportation Research Record, 2470 (2470), 57-64 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 © 2019 B. Goni Ros, V.L. Knoop, B. van Arem, S.P. Hoogendoorn Files PDF 2470_06.pdf 793.41 KB Close viewer /islandora/object/uuid:0ae39528-2cb6-463a-b757-581c541715e9/datastream/OBJ/view