Research on the Setting and Control Method of Centrosymmetric Short Straight Lanes for Signalized Intersections

A new traffic organization method has been proposed to address the issue of traffic congestion caused by oversaturation through traffic during peak hours at signalized intersections. This method involves the installation of approximately centrosymmetric short straight lanes (CSSLs) to facilitate the passage of through vehicles, aiming to improve the traffic efficiency at signalized intersections. Firstly, two types of intersection designs with CSSLs were investigated, along with their operational principles. Secondly, a capacity model for the CSSL was established, taking into account the probability theory and mutual blockage considerations, as well as a delay model based on vehicle accumulation under oversaturated conditions. Finally, the intersection of Nanxu Road and Huangshan South Road in Zhenjiang City was chosen as an example. A simulation scheme was designed using VISSIM software to evaluate the effectiveness of the proposed method by implementing CSSLs before and after the intersection. The simulation results indicate that this method effectively increases the capacity of the oversaturated intersection approaches at the intersection and reduces the average delay. Under different lengths of short through lanes and utilization rates, the capacity of the eastbound short through lane and its adjacent lane increased by 20.7%, and the average delay decreased by 14.2% in all cases. Furthermore, a sensitivity analysis was conducted to examine the impact of short through lane capacity and the number of short through lanes on intersection capacity under different traffic volume levels. This analysis provides further insights into the influence of the CSSL on intersection capacity.