Research on the Operational Efficiency of the Two-Way Left-Turn Lane

In order to solve the traffic congestion and safety problems caused by the staggered intersection of urban roads, this paper proposes a new traffic organization: a two-way left-turn lane (TWLTL) in the center of the road. Research into the geometric design of the TWLTL is based on the comparison of traditional staggered intersections and alternative traffic organization methods. The minimum width of TWLTL and the spacing of adjacent intersections under different speeds are proposed. The effectiveness of TWLTL is demonstrated through a field data investigation, simulation, and analysis performed with VISSIM software. The applicability analysis of TWLTL was carried out with a combination of different main road traffic volumes and left turn ratios. When the traffic volume is lower than 1,120 veh/h and the left turn ratio is less than 20%, compared with Four-Lane, TWLTL reduces traffic efficiency slightly, but greatly improves safety at the intersection.