A CASE FOR FREEWAY MAINLINE METERING

In this work, the merits of freeway mainline metering as a means of better managing freeway traffic congestion are explored. Freeway mainline metering involves controlling the amount of traffic entering a freeway segment to provide improved travel downstream of the control area. To date, mainline metering has not been applied to a typical urban freeway system, although the concept has been applied successfully to bridges and tunnels. Experiences at these bridges and tunnels indicate that in the presence of a bottleneck, regulating the number of vehicles through the bottleneck will result in improved freeway operations. This study investigates whether regulating mainline vehicle movements can also improve freeway operations without the presence of a bottleneck. Also addressed in this work is whether mainline metering can provide additional benefits over and above typical ramp metering. To evaluate the above hypotheses, the INTRAS simulation model was used to replicate freeway traffic operations. The mainline metering evaluation was based on a variety of mainline volume and on-ramp control conditions. The results indicate that mainline metering can improve freeway operations downstream of the mainline meter. Most importantly, this can be accomplished without increasing the overall delay for vehicles originating upstream of the metering location. In addition, vehicles accessing the freeway from metered on-ramps downstream of the mainline meter are no longer entering a congested freeway mainline, thus reducing overall travel time. These findings appear to indicate that mainline metering is an appropriate freeway management tool.

Language

  • English

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 11-20
  • Monograph Title: Traffic operations, traffic signal systems, and freeway operations 1995
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00714894
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Dec 13 1995 12:00AM