CMF / CRF Details
CMF ID: 8316
Convert diamond interchange to Diverging Diamond Interchange (DDI) or Double Crossover Diamond (DCD)
Description: Convert a diamond interchange to a Diverging Diamond Interchange (DDI) or a Double Crossover Diamond (DCD)
Prior Condition: Diamond interchange
Category: Interchange design
Study: Safety Evaluation of Seven of the Earliest Diverging Diamond Interchanges Installed in the US, Hummer et al., 2016
Star Quality Rating: | [View score details] |
Rating Points Total: | 45 |
Crash Modification Factor (CMF) | |
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Value: | 0.33 |
Adjusted Standard Error: | |
Unadjusted Standard Error: | 0.05 |
Crash Reduction Factor (CRF) | |
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Value: | 67 (This value indicates a decrease in crashes) |
Adjusted Standard Error: | |
Unadjusted Standard Error: | 5 |
Applicability | |
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Crash Type: | Angle |
Crash Severity: | All |
Roadway Types: | Principal Arterial Other Freeways and Expressways |
Street Type: | |
Minimum Number of Lanes: | 3 |
Maximum Number of Lanes: | 6 |
Number of Lanes Direction: | |
Number of Lanes Comment: | |
Crash Weather: | Not specified |
Road Division Type: | Divided by Median |
Minimum Speed Limit: | 35 |
Maximum Speed Limit: | 45 |
Speed Unit: | mph |
Speed Limit Comment: | |
Area Type: | Suburban |
Traffic Volume: | |
Average Traffic Volume: | 30664 Annual Average Daily Traffic (AADT) |
Time of Day: | All |
If countermeasure is intersection-based | |
Intersection Type: | |
Intersection Geometry: | |
Traffic Control: | |
Major Road Traffic Volume: | |
Minor Road Traffic Volume: | |
Average Major Road Volume : | |
Average Minor Road Volume : |
Development Details | |
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Date Range of Data Used: | |
Municipality: | |
State: | KY,MO,NY,TN |
Country: | USA |
Type of Methodology Used: | Simple before/after |
Sample Size (crashes): | 274 crashes before, 59 crashes after |
Sample Size (sites): | 7 sites before, 7 sites after |
Sample Size (site-years): | 28.85 site-years before, 19.03 site-years after |
Other Details | |
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Included in Highway Safety Manual? | No |
Date Added to Clearinghouse: | Jan 17, 2017 |
Comments: | The volume here is the crossover volume. |