Investigation of Driving Behavior at Alternative Intersection Designs and Safety Improvement: A Driver Simulator Study

Alternative intersection designs have been proposed due to their theoretical expected ability to simultaneously enhance traffic safety and operation as a result of reducing the number of conflict points and signal phases. However, this was only achieved at very limited intersection designs which have a very low number of conflict points and under certain traffic conditions. For example, the restricted crossing U-turn (RCUT) intersection, which has the lowest number of conflict points among other proposed intersection designs, has operational advantages at extremely unbalanced traffic volumes. Our shifting movement (SM) intersection design, which has the same number of conflict points as the RCUT intersection, has been proposed to replace the RCUT implementation at intersections with medium to high minor traffic volumes. It was proven that it outperforms the RCUT intersection which has medium to high minor traffic volumes in terms of average delay and throughputs. This study aimed to investigate the safety aspects of this intersection design by utilizing the driving simulator. The effectiveness of using infrastructure to vehicle (I2V) communication for mitigating the confusion at alternative intersections was also investigated in the study. The results indicated that RCUT and SM intersections have similar safety performance and crossing them is safer than crossing the conventional intersection. However, there is a need to improve drivers’ knowledge about the SM intersection, especially regarding the major left-turn movement. Most participants have found that using I2V communication is helpful in understanding the unconventional movement patterns.