Analysis On The Urban Traffic Dynamic Network Assignment With Multi-Modal Travel Mode

With the acceleration of urbanization, the improvement of living standard, the increasing cars of per person, the urban traffic congestion becomes even worse. Meanwhile,with the improvement of the transportation infrastructure network, the travel choice behavior becomes more and more diverse and travel mode change from single-modal to multi-modal.Most of the current researches on the dynamic traffic assignment model, however, focus on the single-modal travel mode and ignore the transfer behavior. Therefore, it is imperative to further deliberate into the dynamic traffic assignment model and algorithm with multi-modal travel modes, in order to improve the operation efficiency of urban transportation network,improve the travel efficiency of travel, help to alleviate traffic congestion. This paper establishes the urban dynamic traffic assignment model and algorithm with multi-modal travel modes, taking into consideration the travel characteristics in the multi-modal transportation network. The major contributions of the paper are as follows:(1) This paper fully elaborates the dynamic traffic assignment model and classifies the dynamic traffic assignment model. Then according to the need of follow model, this paper fully elaborates the dynamic user optimum traffic assignment model, variational inequality model and algorithm.(2) This paper presents a precise definition of travel mode, which is divided it into single-modal and multi-modal, based on the characteristics in the multi-modal transportation network. Modeling framework of urban traffic assignment in the travel multi-modal is described, combining the existing research of traffic assignment. The super network is introduced to build the multi-modal transportation hierarchical networks, which are mutually correlative and independent. Based on that, the decision condition and algorithm with effective path are put forward.(3) The expression of travel cost and travel time are given, considering the transfer behavior and the interference of bus and car. We can add up travel cost and travel time to get the generalized travel costs by linear weight method. On the basis of the established multi-modal travel cost, depending on the dynamic stochastic user equilibrium assignment and the Logit model from the travel modes and path formulation perspective, this paper analyzes multi-modal traffic network equilibrium condition. The variational inequality model equal to the equilibrium condition is build. The existence of the model solution is demonstrated. In order to solve the model, MSA algorithm is utilized.(4) Finally, the virtual traffic network experiment is designed not only to illustrate the practicality, efficiency of the model and algorithm, but also give the dynamic traffic assignment results. The sensitivity of the model parameters is discussed such as the bus and subway frequency, the parking fee of the car, the value parameter. Finally, the alleviating congestion suggestion is thrown out based on the former description.