Exploring the Association between Traffic Safety and Geometric Design Consistency Based on Vehicle Speed Metrics

Past design consistency research has demonstrated the relationship between operating speeds and geometric design features on two-lane rural highways. However, little is known about the relationship between geometric design consistency and traffic safety. In this study, design consistency is referred to as the difference between operating speed and inferred design speed, and design consistency density is measured to account for the effect of elements upstream and downstream of the study element. To perform the design consistency–safety evaluation in the present study, geometric design, roadway inventory, crash, and operating speed data were collected along two case-study highways in central Pennsylvania (U.S. 322 and PA 350). Several count regression model formulations were used to explore the statistical association between design consistency and total crash frequency. A statistically significant positive association between geometric design consistency and safety was found. Design consistency surrounding the study elements was also found to increase the expected crash frequency in the study element. The significant effects of design consistency and design consistency density measures on crash frequency for the two case-study sites indicate that there is value in further considering the relationship between design consistency and safety in future research, particularly in the context of the highway safety manual crash-prediction algorithm.

• Record URL:
  https://doi.org/10.1061/(ASCE)TE.1943-5436.0000553
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/oclc/8674831
• Supplemental Notes:
  • Copyright © 2013 American Society of Civil Engineers
• Authors:
  • Wu, Kun-Feng
  • Donnell, Eric T
  • Himes, Scott C
  • Sasidharan, Lekshmi
• Publication Date: 2013-7

Language

• English

Media Info

• Media Type: Digital/other
• Features: References;
• Pagination: pp 738-748
• Serial:
  • Journal of Transportation Engineering
  • Volume: 139
  • Issue Number: 7
  • Publisher: American Society of Civil Engineers
  • ISSN: 0733-947X
  • Serial URL: https://ascelibrary.org/journal/jtepbs

Subject/Index Terms

• TRT Terms: Geometric design; Highway design; Operating speed; Statistics; Traffic safety; Traffic speed; Two lane highways
• Geographic Terms: Pennsylvania
• Subject Areas: Design; Highways; Safety and Human Factors; I80: Accident Studies; I82: Accidents and Transport Infrastructure;

Filing Info

• Accession Number: 01484309
• Record Type: Publication
• Files: TRIS, ASCE
• Created Date: Jun 12 2013 10:46AM