| Title | Impact of Intersection Angle on Highway Safety |
|---|---|
| Record ID | 79764 |
| Personal Name Creator |
Harkey, David L.; Lan, Bo; Srinivasan, Raghavan; Kumfer, Wesley; Carter, Daniel; Nujjetty, Anusha patel |
| Personal Name Contributor |
Tan, Carol; Eigen, Ana Maria |
| Corporate Creator | United States. Federal Highway Administration. Office of Safety Research and Development |
| Corporate Contributor |
University of North Carolina (System). Highway Safety Research Center |
| Publisher | United States. Federal Highway Administration. Office of Safety Research and Development |
| Publication Date | 20210101 |
| Language | English |
| Abstract | The preferred design for conventional intersections includes adjacent legs that intersect at 90 degrees. However, there are occasions when physical constraints result in intersection angles less than 90 degrees and thus produce skewed intersections. Skewed intersections may create potential safety and operational problems for both motorists and non-motorists. To date, the research on problems related to skewed intersections has been limited, which may explain the lack of consensus among the policies and guidance that now exists in practice. The objective of this study was to derive quantitative relationships between intersection angle and safety for which intersection crashes define safety. The relationships were used to determine appropriate crash modification functions (CMFunction) for reducing or eliminating the skew angle of an intersection, determine if there is a critical minimum angle at which safety is substantially diminished, and assess the need for revising current geometric design policies and practices. Data-mining and -regression techniques were used to identify the most important predictor variables from many independent variables. Data from minor road stop-controlled intersections in Minnesota and Ohio were used to estimate negative binomial regression models using the identified variables. These models were used to derive CMFunctions for rural and urban three- and four-leg intersections. The relationship between the crash modification factor and intersection angle (represented by the CMFunctions) differs from previous studies. Agencies should consider modifying the minimum critical angle for intersections in roadway design policies to be revised to reflect the results of this research. |
| Rosap ID | dot:54782 |
| Rosap URL | https://rosap.ntl.bts.gov/view/dot/54782 |
| TRT Terms | Intersection elements; Intersections; Traffic safety; Crash modification factors |
| General Subjects | Intersection angle; Intersection safety; Crash modification factor; Crash modification function; Skew angle; Negative binomial regression; Stop controlled |
| Geographical Coverage |
United States |
| TRIS Online Accession No |
1762471 |
| Contract Number | DTFH61-11-C-00050 |
| Report Number | FHWA-HRT-20-067 |
| Resource type | Tech Report |
| URL | https://ntlrepository.blob.core.windows.net/lib/79000/79700/79764/FHWA-HRT-20-067.pdf |
| Format | |
| Database | NTL Digital Repository |