An Alternative Design for the Intersections With Limited Traffic Lanes and Queuing Space

Existing unconventional intersection designs mainly apply to large intersections, such as the intersection of two major roads, in which there are numerous lanes on each leg and the allowed queue length is long. This paper presents a new unconventional intersection design to improve the operational efficiency of the intersections with limited traffic lanes and short distance for vehicular queuing, such as the intersections on collector roads. The new design combines the advantage of the tandem control and exit-lanes for left-turn control (CTE). An optimization model is established to maximize the capacity of the intersection under the CTE design in which the allocation of the mixed-usage lane, lane markings, and signal timings are integrated. A case study and extensive numerical analysis are conducted to evaluate the performance of the proposed model. Comparisons are made between the proposed CTE design and the other three designs, namely the tandem design, exit-lanes for left-turn design, and conventional design, under different geometric and traffic demand cases. The results show that CTE design has promising property when the left turn ratio is low to medium (< 50%), and the queue length is limited (<200m).

Automated summary

The paper introduces a new unconventional intersection design and establishes an optimization model to maximize intersection capacity. Through a case study and numerical analysis, it is proven that this design can improve operational efficiency under certain conditions.