Safety Evaluation of Corner Clearance at Signalized Intersections

This study evaluated the safety effects of limited corner clearance at four-legged, signalized intersections. Corner clearance is defined as the distance between an intersection to the nearest adjacent access point. Geometric, traffic, and crash data were obtained for signalized intersections with various corner clearances from two regions in California and city of Charlotte, North Carolina. A cross-sectional analysis was conducted to estimate the effects of corner clearance on the mainline road of the intersection while controlling for other differences among study sites. The crash modification factor (CMF) estimates indicated that less clearance on mainline receiving corners (i.e., the presence of at least one driveway within 50 ft of the signalized intersection) was associated with increases in all crash types, based on the data included in this analysis. Apart from the results for turning crashes, all safety effects for mainline receiving corners were statistically significant at the 90-percent level or greater for total, fatal and injury, rear-end, sideswipe, right-angle, and nighttime crashes. For limited corner clearance on mainline approach corners, the results indicated statistically significant reductions in total, fatal and injury, and rear-end crashes. The results also indicated reductions in sideswipe and nighttime crashes as well as increases in right-angle and turning crashes, but none of these results were statistically significant at the 90-percent level. Improving corner clearance on receiving corners was shown to be a cost-effective strategy for reducing total crashes and fatal and injury crashes at four-legged, signalized intersections.

• Supplemental Notes:
  • This paper was sponsored by TRB committee AHB70 Standing Committee on Access Management.
• Authors:
  • Le, Thanh Q
  • Gross, Frank
  • Harmon, Tim
• Conference:
  • Transportation Research Board 97th Annual Meeting
  • Location: Washington DC, United States
  • Date: 2018-1-7 to 2018-1-11
• Date: 2018

Language

• English

Media Info

• Media Type: Digital/other
• Features: Figures; References; Tables;
• Pagination: 6p

Subject/Index Terms

• TRT Terms: Clearances (Navigation); Crash modification factors; Crash rates; Evaluation and assessment; Highway design; Highway safety; Signalized intersections
• Geographic Terms: California; Charlotte (North Carolina)
• Subject Areas: Highways; Operations and Traffic Management; Safety and Human Factors;

Filing Info

• Accession Number: 01660506
• Record Type: Publication
• Report/Paper Numbers: 18-03676
• Files: TRIS, TRB, ATRI
• Created Date: Feb 20 2018 9:29AM