The Integration of Dynamic Lane Grouping Technique and Signal Timing Optimization for Improving the Mobility of Isolated Intersections

Spatial variations in traffic demand degrade intersection performance that can result in the waste of time-space resources. Existing control strategies of intersections assume fixed lane for movement assignment regardless of demand variations. Dynamic lane grouping (DLG) is one of the intelligent transportation systems techniques in which the lane allocation depends mainly on the real-time movement demand. The settings of intersection signal control depend on lane configuration where a demand-responsive lane allocation strategy will help in providing efficient signal operation with lower delays. This paper investigates the benefits of DLG technique in gaining improvements in the performance of isolated signalized intersections. A model that integrates the identification of optimum lane group combination and optimum signal timing parameters is developed. The objective function of the optimization model is based on the minimization of average intersection delay. A case study is conducted on an isolated signalized intersection in Dhahran city, Saudi Arabia. A comparison between the existing operation with fixed lane grouping and the proposed DLG is made in terms of average intersection delay, cycle length, and maximum lane volume-to-capacity ratio. It is concluded that DLG technique achieves significant reduction in average intersection delay that leads to significant improvement in mobility levels of signalized intersections.