This paper describes the solution of the traffic assignment model under fuzzy information. The assumption about perfect network information is relaxed. The fuzzy algorithm, successive representative method, is proposed in this study. This algorithm assigns a set of O-D trip rates to a transportation network in which the link travel times are fuzzy. The assignment assumes that route choice is based on fuzzy link travel times. The fuzzy travel times are modeled not only as fuzzy numbers, but also as flow dependence. This dependence is accounted for by assuming that the fuzzy travel time for each link is a fuzzy mapping of the flow on that link. Four fuzzy operations are used in the successive representative method, including fuzzy addition, fuzzy multiplication, fuzzy comparison and defuzzification. Our algorithm is exemplified by the road network around Osaka. Sensitivity analysis of the algorithm are also presented.
