Increasing the effectiveness of T-junctions with an innovative geometrical and phasing arrangement

Abstract

Improper usage of control mechanisms at intersections would lead to significant delays resulting in road user frustration. The traditional methods of traffic islands or traffic signals are no longer effective due to the high traffic movements at intersections, heterogeneity of such traffic, and uneven pedestrian movements. To minimize unnecessary delays and improve multi-user satisfaction, there is a need to use advanced traffic management systems which come at an increased cost. This research aims to develop an innovative yet cost-effective arrangement to use the existing traffic signals (modified) with a geometric alteration to reduce delays at T-junctions while catering to the high pedestrian demands effectively. The arrangement proposed in this study is twofold. First, the right turns from the minor road is forced to turn left and subsequently, a U-turn is arranged. Secondly, a signal phasing arrangement to manage the revised turning movements effectively and efficiently is introduced. The proposed arrangement was first designed using theoretical means identifying the proper scenarios, and later it was verified using an existing T-junction (case study) with real traffic and geometric data. For verification, VISSIM traffic simulation software was used after proper calibration to simulate local traffic conditions. Sensitivity analysis was also carried out to test for other possible scenarios. The results of the case study confirm that the proposed design for T-junction can reduce the delays at intersections by around 20 %, increasing the efficiency of the intersection.