Paradoxes In Urban Transportation Network Design Problem

Facing the pressure of the lack of urban transportation infrastructure construction and fund shortage, the urban transportation network design problem becomes the most effective method to solve the urban transportation problem. Especially, the paradox problem which is a counter-example in urban transportation network design problem, plays an important part in solving the urban transportation problem. This thesis is focusing on the research of the paradox phenomena that may occur in the urban transportation network design.On the basis of the present research situation of the paradox problem, this thesis first introduced Braess paradox, then studied the conditions under which Braess paradox occurs, if the link travel time is described by linear or BPR non-linear function, and pointed out the flaw and insufficiency of the studying of Braess paradox under linear link travel time function. The thesis also made a numerical experiment to analyze the difference of occurrence conditions of Braess paradox between linear and BPR non-linear link travel time function.Secondly, considering the emissions generated by vehicles, this thesis discussed emission paradoxes that may occur in the transportation network design, and studied the occurrence conditions of emissions paradoxes under linear link travel time function as well as the BPR non-linear function, and established a mathematical model to avoid emission paradoxes.Finally, this thesis also discussed kinds of paradox phenomena that may occur in stochastic assignment model, including the emission paradoxes.