Analytical investigation on the minimum traffic delay at a three-phase signalized T-type intersection

Abstract

The traffic delay at intersections is crucial for the performance of urban traffic system. This paper analytically investigated the minimum traffic delay at a three-phase T-type intersection. We firstly demonstrate that the minimum traffic delay must be achieved on the surface of the 3D space constituted by the three constraints. Next, we prove that the minimum traffic delay must be achieved on the three borderlines of the surface. Finally, we show that the minimum delay is achieved either on one specific borderline or at the vertex of the surface. In the former case, extra green time is needed for the stream with largest demand, while no extra green time should be assigned to any stream in the latter case.