Field Test of Coordinated Ramp Metering (CRM)

This project has focused on field implementation and testing of a Coordinated Ramp Metering (CRM) algorithm at California State Route 99 Northbound corridor in Sacramento between Calvine Road and the SR50 interchange after 12th Ave. It is a 9 mile long corridor with 11 onramps to which the CRM algorithm has been applied. After refining the CRM algorithm using a microscopic simulation of the test site, the project team worked closely with Caltrans Headquarters Division of Traffic Operation and District 3 Freeway Operation for (a) finalizing the ConOps (b) real-time data acquisition from 2070 controllers in the field and establishing correct data mapping between field detectors and the controller in the CRM algorithm; (c) implementing the CRM algorithms as real-time code running on a PATH computer; (d) estimating realtime traffic state parameters; (e) system integration of all software modules and hardware components; (f) conducting three weeks of dryrun tests, two weeks of progressive switching-on, system tuning and preliminary test, and five weeks of extensive testing and data collection; and (h) accomplishing performance analysis with PeMS data. By comparing the VMT (Vehicle Miles Travelled), VHT (Vehicle Hours Travelled), and the ratio VMT/VHT during field tests in 2017 with data from 2016 in the same period, during the AM peak hours, VMT/VHT was increased by 7.25% on average, which indicated traffic improvement. During the PM peak hours, VMT/VHT decreased by 0.44% on average, which meant no traffic improvement. The reason was that the traffic was not congested most of the time in PM hours. This suggests that the CRM algorithm tested could be more effective for congested traffic.


  • English

Media Info

  • Media Type: Digital/other
  • Edition: Final Report
  • Features: Appendices; Figures; References; Tables;
  • Pagination: 136p

Subject/Index Terms

Filing Info

  • Accession Number: 01640196
  • Record Type: Publication
  • Report/Paper Numbers: CA16-2445, UCB-ITS-PRR-2017-01
  • Contract Numbers: 65A0537
  • Created Date: Jun 30 2017 7:45PM