Sensitivity Analysis of Freeway Capacity at a Complex Weaving Segment

Freeway mainline and ramp flows interact at weaving segments. During traffic peaks, drivers' intensive weaving maneuvers yield frequent interferences between vehicles, which disturb flow and reduce freeway capacity and safety. Thus, effective freeway operation strategies require weaving capacity estimations to assess real-time traffic states. Generally, existing weaving capacity estimation methods are classified as theoretical or empirical. However, some of the parameters adopted in these existing methods are insufficient as inputs for freeway operation. This study aimed to fill that gap. The study began with a determination of all of the possible weaving parameters that may be used in traffic control. Then, a micro-simulation model was calibrated with field data to replicate the capacity of a two-sided weaving segment. With the calibrated micro-simulation model, a sensitivity analysis was systematically performed to determine the weaving parameters' potential impact on weaving capacity. The results showed that the simulated weaving segment capacity is highly sensitive to speed, while the variations in bottleneck capacity reductions are sensitive to traffic flow rates and their proportions. Finally, an empirical model for capacity estimation was established based on the sensitivity analysis results. The developed model could be applied to dynamic freeway operation strategies to accurately estimate traffic states.

Language

  • English

Media Info

  • Media Type: Web
  • Features: References;
  • Pagination: pp 596-608
  • Monograph Title: CICTP 2014: Safe, Smart, and Sustainable Multimodal Transportation Systems

Subject/Index Terms

Filing Info

  • Accession Number: 01532911
  • Record Type: Publication
  • ISBN: 9780784413623
  • Files: TRIS, ASCE
  • Created Date: Jul 2 2014 3:02PM