Development of a framework for evaluating yellow timing at signalized intersections.

Details

• Creators:
  Rakha, Hesham ; El-Shawarby, Ihab ; Amer, Ahmed
• Corporate Creators:
  Virginia Center for Transportation Innovation and Research
• Corporate Contributors:
  Virginia. Dept. of Transportation ; United States. Federal Highway Administration
• Subject/TRT Terms:
  • Yellow interval (Traffic signal cycle)
  • Traffic signal intervals
  • Signalized intersections
  • Evaluation
  • Crashes
  • Safety and security
  • Traffic safety
  • Highway safety Yellow Timing at Signalized Intersections
• Publication/ Report Number:
  FHWA/VCTIR 11-R12;VCTIR 11-R12
• Resource Type:
  Tech Report
• Geographical Coverage:
  Virginia
• Edition:
  Final contract.
• Corporate Publisher:
  Virginia Center for Transportation Innovation and Research
• Abstract:
  Studies show that the proper design of clearance intervals has significant implications for intersection safety. For ; example, in 2001, approximately 218,000 red-light-running crashes occurred at signalized intersections in the United States. ; These crashes resulted in nearly 181,000 injuries and 880 fatalities and an economic loss of $14 billion. Driver behavior while ; the driver is approaching high-speed signalized intersections at the onset of a yellow indication varies as a function of many ; parameters. Some of these parameters are related to the driver’s attributes, e.g., age, gender, perception-reaction time, and ; acceptable deceleration levels. Other parameters that relate to the intersection geometry include the approach speed, distance, and ; time to the intersection at the onset of the yellow indication. ; This study developed a novice approach for computing the clearance interval duration that explicitly accounts for the ; reliability of the design (probability that drivers are not caught in a dilemma zone). Lookup tables based on the limited data ; available from this study are provided to illustrate how the framework could be used in the design of yellow timings. The ; approach was developed using data gathered along Virginia’s Smart Road test facility for dry and clear weather conditions for ; two approach speeds: 72.4 km/h (45 mph) and 88.5 km/h (55 mph). Each dataset includes a complete tracking of the vehicle ; every deci-second within 150 m (500 ft) before and after the intersection. A total of 3,454 stop-run records were gathered. These ; include 1,727 records (687 running records and 1,040 stopping records) for an approach speed of 45 mph and 1,727 records (625 ; running records and 1,102 stopping records) for an approach speed of 55 mph. Using these data, models that characterize driver ; perception-reaction times and deceleration levels were developed. ; The application of the proposed approach demonstrates that the current design procedures are consistent with a ; reliability level of 98%.
  More +
• Format:
  PDF
• Funding:
  87584
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/24528/dot_24528_DS1.pdf
• File Type:
  [PDF - 2.37 MB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:deebd7f3944c3e689afd1300a79de483043272d1bb6707532d647cc3b7d431369f428059ec5844cd0f9ffb96098aa26392df2f31ecde440af1d98934282df512