CMF / CRF Details
CMF ID: 4674
Decrease freeway ramp spacing from infinity to S (ft) with/without auxiliary lane
Description: Decreasing ramp spacing (painted gore to painted gore) on freeway segments from infinity to S (ft) with or without exisiting auxiliary lane
Prior Condition: Ramp spacing approaching infinity, which represents a basic freeway segment with no ramps.
Category: Access management
Study: Safety Evaluation of Geometric Design Criteria for Entrance-Exit Ramp Spacing and Auxiliary Lane Use, Le, T. Q., and Porter, R. J., 2012
Image: View the countermeasure image.
Star Quality Rating: | [View score details] |
Rating Points Total: | 125 |
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Applicability | |
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Crash Type: | Not specified |
Crash Severity: | All |
Roadway Types: | Principal Arterial Interstate |
Street Type: | |
Minimum Number of Lanes: | |
Maximum Number of Lanes: | |
Number of Lanes Direction: | |
Number of Lanes Comment: | |
Crash Weather: | Not specified |
Road Division Type: | Divided by Median |
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Area Type: | Not specified |
Traffic Volume: | Minimum of 5,134 to Maximum of 153,500 Average Daily Traffic (ADT) |
Average Traffic Volume: | 43,158 Average Daily Traffic (ADT) |
Time of Day: | Not specified |
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Development Details | |
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Date Range of Data Used: | 2006 to 2008 |
Municipality: | |
State: | CA,WA |
Country: | USA |
Type of Methodology Used: | Regression cross-section |
Sample Size (site-years): | 1212 site-years |