CMF / CRF Details
CMF ID: 11018
Install Texas U-Turn (Texas Turnaround)
Description: Texas U-turns allows vehicles traveling on a one-way frontage road to access the opposing direction one-way frontage road via a U-turn before the terminal intersections at the diamond interchange. This technique removes two potential left-turn maneuvers from the adjacent at-grade intersections.
Prior Condition: No Prior Condition(s)
Category: Intersection geometry
Study: Safety Evaluation for Turnarounds at Diamond Interchanges: Assessing the Texas U-Turn, Dixon et al., 2018
| Star Quality Rating: |  [View score details] |
| Rating Points Total: | 115 |
| Crash Modification Factor (CMF) | |
|---|---|
| Value: | 2.014 |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 0.3278 |
| Crash Reduction Factor (CRF) | |
|---|---|
| Value: | -101.4 (This value indicates an increase in crashes) |
| Adjusted Standard Error: | |
| Unadjusted Standard Error: | 32.78 |
| Applicability | |
|---|---|
| Crash Type: | All |
| Crash Severity: | All |
| Roadway Types: | All |
| Street Type: | |
| Minimum Number of Lanes: | 2 |
| Maximum Number of Lanes: | 4 |
| 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: | 55 |
| Speed Unit: | mph |
| Speed Limit Comment: | |
| Area Type: | Not specified |
| Traffic Volume: | |
| Average Traffic Volume: | |
| Time of Day: | All |
| If countermeasure is intersection-based | |
| Intersection Type: | Roadway/roadway (interchange ramp terminal) |
| Intersection Geometry: | |
| Traffic Control: | Signalized |
| Major Road Traffic Volume: | |
| Minor Road Traffic Volume: | |
| Average Major Road Volume : | |
| Average Minor Road Volume : | |
| Development Details | |
|---|---|
| Date Range of Data Used: | 2009 to 2015 |
| Municipality: | |
| State: | TX |
| Country: | USA |
| Type of Methodology Used: | |
| Other Details | |
|---|---|
| Included in Highway Safety Manual? | No |
| Date Added to Clearinghouse: | Nov 09, 2021 |
| Comments: | This CMF is for adding additional frontage road lanes to frontage roads with 2 - 4 lanes. |
