Loading...

User assessment of traffic quality measures on freeway weaving segments

Dehghani Sanij, M. S ; Sharif University of Technology | 2008

508 Viewed
  1. Type of Document: Article
  2. DOI: 10.1061/40995(322)77
  3. Publisher: ASCE - American Society of Civil Engineers , 2008
  4. Abstract:
  5. According to the Highway Capacity Manual, definitions of level of service for freeways are generally in terms of such service measures as freedom to maneuver, change in free flow speed, and drivers' physical and psychological comfort. These quality measures are inherently uncertain and are highly dependent on user perceptions. However, users' perception of traffic operational conditions has not been explicitly considered in defining LOS categories. This study attempt to evaluate freeways LOS and other quality measures describing LOS, based on user perception. Therefore, twenty 1-minute video clips of a weaving freeway segment were shown to users. For each video clip, users' perceptions of LOS, maneuverability, flow condition and congestion of the traffic stream were surveyed. Using fuzzy set theory, fuzzy categories for these traffic characteristics were developed. The developed categories for each quality measure were analyzed. They were also compared to the HCM LOS categories. It was found that fuzzy categories of LOS, maneuverability and flow condition are noticeably similar in terms of category range and spacing. In addition, perceived categories of these three quality measures are not necessarily similar to HCM LOS categories in terms of category range. It was also observed that for traffic conditions having HCM LOS A through E, users perceive service on three-to-four levels. The findings also suggest that when traffic conditions have HCM LOS A through E, the congestion within the traffic stream is acceptable for users. Copyright 2008 ASCE
  6. Keywords:
  7. Fuzzy set theory ; Highway engineering ; Motor transportation ; Video cameras ; Highway capacity manual ; Level of Service ; Operational conditions ; Psychological comforts ; Quality measures ; Traffic characteristics ; Traffic conditions ; Users' perception ; Traffic congestion
  8. Source: 6th International Conference on Traffic and Transportation Studies Congress 2008: Traffic and Transportation Studies Congress 2008, ICTTS 2008, Nanning, 5 August 2008 through 7 August 2008 ; Volume 322 , 2008 , Pages 827-836 ; 9780784409954 (ISBN)
  9. URL: https://ascelibrary.org/doi/abs/10.1061/40995%28322%2977