Details:

• Creators:
  Drakopoulos, Alex ; Liu, Yue ; Horowitz, Alan

  Drakopoulos, Alex ; Liu, Yue ; Horowitz, Alan Less -
• Corporate Creators:
  National Center for Freight and Infrastructure Research and Education (U.S.)
• Corporate Contributors:
  United States. Dept. of Transportation. Research and Innovative Technology Administration
• Subject/TRT Terms:
  [+]

  Car Following Freeway Operations Headways Heavy Vehicles Highway Capacity Level Of Service Passenger Car Equivalence Traffic Congestion Traffic Measurement Traffic Speed
• Publication/ Report Number:
  CFIRE 04-17
• Resource Type:
  Tech Report
• Geographical Coverage:
  United States
• Corporate Publisher:
  National Center for Freight and Infrastructure Research and Education (U.S.)
• Abstract:
  Information contained in the Highway Capacity Manual on the influence heavy vehicles have on freeway traffic
  
  operations has been based on few field data collection efforts and relied mostly on traffic simulation efforts. In the
  
  2010 Manual heavy vehicle impact is evaluated based on “passenger car equivalent” values for buses/trucks and
  
  recreational vehicles. These values were calibrated for relatively uncongested freeway conditions (levels of service
  
  A through C) since inadequate field data on heavy vehicle behavior under congested conditions were available.
  
  Field-collected headway information was based on the average headway for vehicles in a particular class,
  
  regardless of the type of vehicle they were following.
  
  The goal of the present effort was to collect and analyze freeway field data on headways with an emphasis on
  
  heavy vehicle behavior under lower speeds typically associated with a level of service E (capacity) or F (forcedflow
  
  conditions). Contrary to previous efforts incorporated in the Highway Capacity Manual methodology, that
  
  disregarded the effect a leading vehicle has on headways, headway information was collected for ten
  
  leading/following vehicle pair types containing at least one passenger car (for example buses followed by
  
  passenger cars). Headway statistics were analyzed for nine speed ranges (up to 20 mph; 20-25 mph; 25-30 mph;
  
  30-35 mph; 35-40 mph; 40-45 mph; 45-50 mph; 50-55 mph; and 55+ mph) and ten vehicle pair types.
  
  Passenger car equivalent values were derived for each speed range based on the average headway for a specific
  
  vehicle pair type divided by the average headway between passenger cars. A total of 3,981,810 individual vehicle
  
  records were used to construct the 2,645,210 vehicle pair records for which headway statistics were compiled. All
  
  analyzed information originated from the Milwaukee County, Wisconsin urban freeway system. Leading and
  
  following vehicle class and speed were found to significantly influence headways and passenger car equivalent
  
  values.
  
  
• Format:
  PDF
• Funding:
  244K672
• Collection(s):
  University Transportation Centers US Transportation Collection
• Main Document Checksum:
  [+]

  urn:sha256:e7e072524cea0ec014e7b4246b607250a642145052106cfbae3ef3aebfca39f9
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/27779/dot_27779_DS1.pdf
• File Type:
  [PDF-3.01 MB]