Safety Analysis of RCUT Intersection

The safety of intersections on a major corridor is always a concern because of the high-risk vehicle maneuvers intertwined with high operating speed. Significant number of crashes at such intersections is angled-collisions with a high percentage of fatalities and injuries. This is especially true at intersections with a two-way stop-sign control (TWSC) where vehicles on a low-speed, minor roadway must cross or merge into the path of high-speed vehicles on the major highway. The crashes often involve a vehicle entering the intersection from the stop approach and a vehicle travelling high speed on the main approach. While sign and pavement marking may have an impact, they are not considered as effective as eliminating the through and left-turn movement from the minor street. For a signalized four-leg (4SG) intersection, an exclusive left-turn signal phase does promote safety, but it often results in a lower intersection capacity and the excessive delay, particularly during rush hours.One relatively new countermeasure, called Restricted Crossing U-turn (RCUT) has gained significant interest. The RCUT is aimed to reduce the number of conflicting point (thus, reducing crashes and crash severity) and increase intersection capacity. Left-turning and crossing vehicles on the minor road are forced to turn right at the intersection and then making a U- turn a short distance away. Clearly, the RCUT is suitable for an intersection of a major arterial and a minor roadway with significantly smaller traffic volumeThis paper evaluates the safety benefit of six RCUTs in Louisiana. Unlike the previous studies, this investigation covers both the RCUT intersection only and RCUT system (consisting of the intersection, two U-turns and segments in between). The crash analysis shows a 100% reduction in fatalities, 41.5% in injuries and 22.3% in property damage only crash for the RCUT intersection only, and less impressive reductions for the RCUT system. The review of the original crash reports greatly benefits the investigation on why the crashes increased at few locations, thus, provides the valuable information on how to correct these crash problems through the detailed design and traffic control. The safety improvement plus the high ratio of benefit to cost strongly demonstrate that the RCUT is an effective and economically justified countermeasure on high-speed roadways in both rural and urban areas.