Delay Model for Right-Turn Lanes at Signalized Intersections with Uniform Arrivals and Right Turns on Red

Abstract

A framework for the future incorporation of proper right-turn-on-red (RTOR) delay estimation procedures into the Highway Capacity Manual signalized intersection chapters is provided. Models of uniform delay that are based on queuing theory and that incorporate RTORs are developed. Queuing accumulation polygons (QAPs) were used to analyze the effects of RTOR operations. A classification system for placement of any signal phasing scheme into one of four classes based on a sequence of three red regimes and one green regime is showcased. The three red regimes are characterized by the traffic stream that is given priority over the RTOR traffic during the red regime. One red regime gives priority to the intersecting and conflicting traffic. The second red regime gives priority to the intersecting but nonconflicting traffic. The third red regime prioritizes the opposing and conflicting traffic. It is further demonstrated that the four classes of signal phasing schemes result in one of two general QAP patterns. The first pattern consists of two conflicting regimes, followed by two nonconflicting regimes. The second consists of alternating conflicting and nonconflicting regimes. Models used to calculate delay for each basic pattern are presented. The parameters needed to calculate delays based on the models that were developed are discussed. Furthermore, models from related research that may be used to develop any necessary parameter estimates are also presented.