Analyses of Vehicle Trajectories When Leaving the Traveled Way on Curved, Superelevated Road Sections

The curvature and surface slope are known to affect vehicle dynamics and influence trajectories. On curved roadway sections, the vehicle can leave the road at a sharper angle and with superelevation the vehicle may have greater vertical force components. Consequently, impacts with roadside barriers could potentially result in a higher impact severity. The objective of this effort was to apply vehicle dynamics tools to assess the trajectories of vehicles leaving the traveled way on curved, superelevated roadway sections. The intent was to develop a better understanding of the influence of various roadway curvatures, superelevation, and shoulder or roadside designs on these trajectories to develop recommendations for effective barrier features and placement in these situations. The analyses considered two types of vehicles, six roadway curvature and superelevations rates, three impact angles, and three speeds. Data is presented comparing changes in roll, pitch, and yaw for vehicles on a roadway departure trajectory. Normalize trajectory plots were used to the potential effectiveness of three types of barrier relative to override and underride. Graphs indicating effective placement locations were generated for the three barrier types. Tabular summaries of the relative effectiveness measures are also provided. Efforts continue on this research to develop recommendation for the selection and placement of barriers on curved, superelevated roadway sections.

• 
• Supplemental Notes:
  • This paper was sponsored by TRB committee AFB20 Roadside Safety Design.
• Corporate Authors:

  Transportation Research Board

  500 Fifth Street, NW
  Washington, DC  United States  20001
• Authors:
  • Marzougui, Dhafer
  • Opiela, Kenneth S
  • Kan, Cing-Dao (Steve)
• Conference:
  • Transportation Research Board 94th Annual Meeting
  • Location: Washington DC, United States
  • Date: 2015-1-11 to 2015-1-15
• Date: 2015

Language

• English

Media Info

• Media Type: Digital/other
• Features: Figures; References; Tables;
• Pagination: 22p
• Monograph Title: TRB 94th Annual Meeting Compendium of Papers

Subject/Index Terms

• TRT Terms: Crash severity; Highway bridges; Ran off road crashes; Roadside hazards; Roadside structures; Speed; Superelevation; Vehicle trajectories
• Subject Areas: Highways; Safety and Human Factors; I85: Safety Devices used in Transport Infrastructure;

Filing Info

• Accession Number: 01559021
• Record Type: Publication
• Report/Paper Numbers: 15-5838
• Files: PRP, TRIS, TRB, ATRI
• Created Date: Mar 31 2015 9:09AM