Maximizing the Traffic Throughput of Turn Bays at a Signalized Intersection Approach

Abstract

This paper proposes a method to maximize the throughput of a single-lane approach with a branched configuration (one-lane arterial with multiple turn bays at the intersection approach). Field observations determined that, for such an intersection approach, turn bays can be efficiently used only for a limited amount of time after the start of green, and setting the maximum green too high will result in loss of efficiency. The proposed method provides equations for estimating the maximum green that would maximize throughput and suggests repeating the phase twice in the cycle, such that the multilane section can be filled up each time before the green is given. After the new approach is presented and discussed, it is applied to modify the signalization pattern of an existing signalized intersection. This study site is along a single-lane arterial with three lanes at the stop bar: left turn, through and right turn. The new signalization pattern is applied at the study site, and the field evaluation of the before and after conditions are reported. It was concluded that the new scheme increased the throughput of the subject approach by 12.6%.