Harnessing the Power of Microscopic Simulation to Evaluate Freeway Service Patrols

Public agencies have been increasing their use of Freeway Service Patrols (FSPs) to help with incident response and motorist support. FSPs are also a useful tool in detecting and verifying incidents, thus minimizing the duration and the impacts on traffic. A quantitative assessment of the impacts on incident duration of different FSP service strategies, including various FSP vehicle headways and dispatch policies, will provide guidance and additional motivation for the widespread deployment of such systems. Using the microscopic simulation software PARAMICS, this work evaluated the benefits of FSPs in reducing incident duration, which in turn has a considerable positive effect on total vehicle hours of travel during an incident. The authors applied PARAMICS to simulate various strategies related to FSP operations through an Application Programming Interface (API). PARAMICS is suitable for applying a combination of simulation modules, such as random spatial and temporal incident generation, and modeling FSP service headway and restrictions of FSP assignments in the network. Analysis of the simulation revealed that both dispatch policies and the headway between FSP vehicles affected the incident response times and consequently the duration of incidents as well as vehicle hours of travel. The effects of different dispatch policies diminished as the headways of FSPs increased. Results also revealed that as the severity of incidents (in terms of number of lanes blocked) increases the benefits of FSP programs increases, by reducing delay through faster detection, response and clearance.


  • English

Media Info

  • Media Type: CD-ROM
  • Features: Figures; Maps; References; Tables;
  • Pagination: 18p
  • Monograph Title: TRB 86th Annual Meeting Compendium of Papers CD-ROM

Subject/Index Terms

Filing Info

  • Accession Number: 01049578
  • Record Type: Publication
  • Report/Paper Numbers: 07-3360
  • Files: TRIS, TRB
  • Created Date: Feb 8 2007 8:03PM