Research on the Optimal Method of Cycle Length for Signalized Intersection

Abstract

Webster's method (TRRL) and the ARRB method are the main timing methods for isolated signalized intersection. But they are not adequate for high density and low traffic flow, and highly saturated traffic conditions. A traffic intensity model is established in the paper as the optimized index of cycle length according to two parameters, traffic flow and time occupancy. The optimized modes were given for ordinary 2-5 critical phase intersection. The validation of the method was testified from a videotape of intersection operation at a series of intersections of Chanchun in China. The value of cycle length can match the actual traffic conditions, and is better than the value computed by the TRRL method or the ARRB method. The c-1 method can be used for cycle length optimization. A timing illustration for 4 critical phase intersection is given.