U.S. Department of Transportation
Federal Highway Administration
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Washington, DC 20590
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Federal Highway Administration Research and Technology
Coordinating, Developing, and Delivering Highway Transportation Innovations
REPORT |
This report is an archived publication and may contain dated technical, contact, and link information |
Publication Number: FHWA-HRT-21-075 Date: August 2021 |
Publication Number: FHWA-HRT-21-075 Date: August 2021 |
PDF Version (7.34 MB)
Technical Report Documentation Page
1. Report No.
FHWA-HRT-21-075 |
2. Government Accession No. | 3 Recipient's Catalog No. | ||
4. Title and Subtitle
Developing Crash Modification Factors for Guardrails, Utility Poles, and Side-Slope Improvements |
5. Report Date
August 2021 |
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6. Performing Organization Code | ||||
7. Author(s)
Raul Avelar (ORCID: 0000-0002-3962-1758), Karen Dixon (ORCID: 0000-0002-8431-9304), Sruthi Ashraf (ORCID: 0000-0002-3304-9682), Ankit Jhamb (ORCID: 0000-0002-6123-9352) |
8. Performing Organization Report No. | |||
9. Performing Organization Name and Address
Texas A&M Transportation Institute |
10. Work Unit No. (TRAIS) | |||
11. Contract or Grant No.
DTFH6116D00039-0002 |
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12. Sponsoring Agency Name and Address
Federal Highway Administration |
13. Type of Report and Period Covered
Report; May 2017–April 2021 |
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14. Sponsoring Agency Code
HRDS-20 |
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15. Supplementary Notes
This report was prepared for the Federal Highway Administration (FHWA) Office of Safety Research and Development under Contract DTFH6116D00039-0002. The FHWA Development of Crash Modification Factors program and task manager for this project was Roya Amjadi (ORCID: 0000-0001-7672-8485). |
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16. Abstract
Through this project, researchers evaluated the safety effects of guardrails, utility poles, and side slopes using safety data from Indiana and Pennsylvania. Safety evaluations in this project focused on total, fatal-and-injury, and roadway-departure crash risk. Crash modification factors (CMFs) and benefit–cost (B/C) ratios were developed for the safety improvements (guardrails, utility poles, and side slopes) of interest. The CMFs for protecting utility poles with guardrails were not statistically significant for total and roadway-departure crashes (CMF values were 0.89 and 1.52, depending on how close the utility poles were to the roadway). The CMFs for fatal-and-injury crashes were statistically significant (CMFs of 0.524 and 0.433, depending on pole proximity to the roadway). Results for CMFs developed for pole removal in terms of fatal-and-injury crashes indicated a statistically significant CMF of 0.656. For pole relocation, this evaluation found a statistically significant CMF of 0.866 on total crashes. Finally, estimated CMFs for side-slope flattening indicated reductions in total and roadway-departure crashes. The statistically significant CMFs varied between 0.923 and 0.936 for total crashes and between 0.784 and 0.951 for roadway-departure crashes, depending on the initial and final flattened-slope values.
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17. Key Words
CMF, crash modification factor, roadside, slope, guardrail, utility poles |
18. Distribution Statement
No restrictions. This document is available to the public through the National Technical Information Service, Springfield, VA 22161. |
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19. Security Classification (of this report) Unclassified |
20. Security Classification (of this page) Unclassified |
21. No. of Pages
66 |
22. Price
N/A |
Form DOT F 1700.7 (8-72) | Reproduction of completed page authorized |