CMF / CRF Details
CMF ID: 10064
Change horizontal curve radius, posted speed and superelevation
Description: The safety effects of changing horizontal curve radius, posted speed limit, superelevation rate and various combinations of these elements.
Prior Condition: No Prior Condition(s)
Category: Alignment
Study: Reducing Roadway Departure Crashes at Horizontal Curve Sections on Two-lane Rural Highways, Donnell et al., 2019
| Star Quality Rating: |  [View score details] |
| Rating Points Total: | 125 |
| Crash Modification Factor (CMF) | |
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| Crash Reduction Factor (CRF) | |
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| Applicability | |
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| Crash Type: | Fixed object,Head on,Run off road,Sideswipe |
| Crash Severity: | All |
| Roadway Types: | Not specified |
| Street Type: | |
| Minimum Number of Lanes: | 2 |
| Maximum Number of Lanes: | 2 |
| Number of Lanes Direction: | |
| Number of Lanes Comment: | |
| Crash Weather: | Not specified |
| Road Division Type: | Undivided |
| Minimum Speed Limit: | 20 |
| Maximum Speed Limit: | 55 |
| Speed Unit: | mph |
| Speed Limit Comment: | |
| Area Type: | Rural |
| Traffic Volume: | Minimum of 15 to Maximum of 27224 Annual Average Daily Traffic (AADT) |
| Average Traffic Volume: | 4239 Annual Average Daily Traffic (AADT) |
| Time of Day: | All |
| If countermeasure is intersection-based | |
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| Development Details | |
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| Date Range of Data Used: | 2008 to 2013 |
| Municipality: | |
| State: | IN,PA |
| Country: | USA |
| Type of Methodology Used: | Regression cross-section |
| Sample Size (crashes): | 1428 crashes |
| Sample Size (sites): | 889 sites |
| Sample Size (miles): | 166.4 miles |
