EFFICIENCY ELIMINATION OF LEFT TURNS AT INTERSECTIONS

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Abstract

Eliminating left turns at intersections significantly increases traffic capacity at intersections in urban environments. Simplified traffic light control phases reduce the "dead" time between phases, reducing congestion and speeding up traffic. Directly banning or replacing left turns (via U-loops or Michigan Left circuits) reduces delays, increases average speed, and reduces accidents. However, a triple detour slightly increases the distance traveled. This article includes real numerical examples, formulas for calculating throughput, and circuit drawings that show the balance between efficiency and safety. Based on the analysis of world practice (Europe, Asia, USA), it has been revealed that the elimination of left maneuvers reduces the number of conflict points to 30-40% and increases the average speed of traffic by 10-15%. The calculations of the throughput using the formulas of Brushwood and Webster, as well as the modeling of traffic flows under different scenarios of traffic organization are presented. The results show that the exclusion of left turns is especially effective in conditions of high intensity (> 3,500 vehicles per hour) and limited dimensions of the road network.

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References

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Published
2026-09-18
Issue
No. 2 (78) (2026): Известия Кыргызского государственного технического университета имени И. Раззакова
Section
TRANSPORT AND ROBOTICS

How to Cite

EFFICIENCY ELIMINATION OF LEFT TURNS AT INTERSECTIONS. (2026). THE BULLETIN OF I.RAZZAKOV KYRGYZ STATE TECHNICAL UNIVERSITY, 2 (78), 185-193. https://journal.kstu.kg/index.php/izvestiia/article/view/16

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