Characterize dynamic dilemma zone and minimize its effect at signalized intersections.

Details

• Creators:
  Wei, Heng
• Corporate Creators:
  University of Cincinnati. Department of Civil and Environmental Engineering
• Corporate Contributors:
  Ohio Transportation Consortium
• Subject/TRT Terms:
  • Dilemma zone
  • Signalized intersections
  • Dynamic dilemma zone
• Resource Type:
  Tech Report
• Geographical Coverage:
  Ohio
• Corporate Publisher:
  Ohio Transportation Consortium
• Abstract:
  Dilemma zone at signalized intersection has been recognized as a major potential causing rearend ; and right-angle crashes, and has been widely studied by researches since it was initially ; proposed as the GHM model in 1960. However, concepts conventionally defined to represent the ; yellow phase dilemma lack integrity. This research conducts a comprehensive literature review ; with attempt to clarify the interrelationship among dilemma zone, option zone, and indecision ; (decision) zone, and to develop a heuristic framework to present the contributing factors in ; dilemma zone modeling. A new method for modelling the locations and lengths of the dilemma ; zone using video-capture techniques and vehicle trajectory data is presented in this report. First, ; dilemma zone is mathematically modeled based on the GHM model. Then, field-observed ; trajectory data extracted by the video-capturing-based approach are used to calibrate the ; contributing factors involved in the dilemma zone model. The high accuracy of the time-based ; trajectory data has significantly enhanced the accuracy of the calibrated dilemma zone models. ; Two sets of trajectories are explored for calibrating the dilemma zone contributing factors. One ; is concerned with maximum yellow-onset safe passing distance and minimum yellow-onset ; stopping distance. The other is concerned with Xth percentile yellow-onset passing distance and ; (100-X)th percentile stopping distance for the prevailing travel behaviors. The latter alternative ; actually precludes “too conservative” and “too aggressive” maneuvers in response to yellow ; indications. ; One critically important result is the dilemma zone look-up charts that are developed ; based on the calibrated dilemma zone models. Such charts provide a convenient tool to identify ; the locations and lengths of dilemma zones for any speed and yellow duration conditions. ; Additionally, impact of arrival type and vehicle types are also explored. Results reveal that ; traffic in a good progression (Arrival Type ≥ 4) has a further option zone. It is also discovered ; that the length of option zone decreases as the vehicle size increases, while the downstream ; boundary of option zone is further from the stop line as the vehicle size increases. In overall, this ; project aims to conduct a preliminary research for providing a proof of concept about the ; modeling of dynamic dilemma zones, and validating the feasibility of the methodology for ; calibrating the dilemma zone model using trajectory data. The methodology used in this study ; establishes a solid basis for future research of the optimum signal detection placement and ; related dilemma zone protection problems with consideration of multi-speed protection. ; This project is granted by the Ohio Transportation Consortium (OTC). The research team ; is thankful to Dr. Ping Yi at University of Akron and staffs at OTC for their strong support to the ; project. Gratitude goes to Ph.D. students, Mr. Zhixia Li and Mr. Qingyi Ai, and M.S. students, ; Mr. Vijay Krishna Nemalapuri and Mr. Sudhir Reddy Itekyala for their effective assistances in ; field data collection. In particular, Mr. Zhixia Li took the lead in data collection and analysis and ; participated in drafting the report. Finally, the research team also expresses our thanks to Ms. ; Brenda Slaughter, senior Grant Administrator at UC Sponsored Research Services and Mr. Tom ; Davis, senior Grant Administrator at UC Department of Civil and Environmental Engineering ; for their administrative support. This research could be not successfully finished without all their ; active participations, critical contributions, and strong supports.
  More +
• Format:
  PDF
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/20589/dot_20589_DS1.pdf
• File Type:
  [PDF - 3.10 MB]
• Collection(s):
  University Transportation Centers ; US Transportation Collection
• Main Document Checksum:
  urn:sha-512:c3ee4f77622cb9a12aeb0a6afb0d99ec80d884a2fb235949fbdab405b2d762cbae268ab824cc21b8347a2efdb8f65777157363309f719fd1d7da0d8e451ec553