Braess paradox and robustness of traffic networks under stochastic user equilibrium

The Braess paradox is an important phenomenon in the traffic network, and the robustness is a characteristic that measures the network system performance under interference. Study of traffic network paradox and its robustness is an important topic of traffic assignment. In this paper, we investigate the traffic network under elastic demand, its robustness and paradox under stochastic user equilibrium. Using the Logit model and Braess’ network, we find that paradox occurs when the congestion of a newly added road meets certain criterion. Paradox severity and the ranking of the network components are both affected by the new congestion. This finding can be applied in the planning of urban traffic network.