MINIMUM MERGING SECTION LENGTHS FOR TRIPLE LEFT-TURN LANES WITH DOWNSTREAM LANE REDUCTIONS

This paper discusses triple left turns (TLTs), an alternative to handling at-grade signalized intersections with severe left-turn capacity and operational problems. A TLT allows 3 lanes of traffic to turn left simultaneously during a (usually) protected left-turn phase. Studies have shown that TLTs greatly increased left-turn capacities. The first section provides an overview of the methodology applied in this study to develop models to determine the minimum merging section lengths based on data generated by simulation models. Critical variables considered in the simulation models are introduced in the next 2 sections. The simulation modeling process is then described in detail, followed by the method used to determine tabulated guidelines for minimum merging sections. The last section summarizes and provides conclusions for this research.