关键词: 交通运输规划与管理, 交叉巢式Logit, 随机用户均衡, 等级性道路网络, 路径选择行为, 可变信息板

Abstract: Network traffic assignment and cross-nested Logit(CNL)model are investigated based on road hierarchy and VMS information. Supposing some main roads are installed with VMS equipment, the impact coefficients on traffic flow by VMS and the allocation coefficients in CNL model are calculated with road grade and a new attenuation factor of information utility that is formulated by integrating power and exponential ones. For hierarchical road network, CNL route choice model and its equivalent mathematical programming are established under the stochastic user equilibrium, and then a network flow allocation algorithm is proposed. The model and algorithm presented are examined with an example network. Calculations and analyses lead to some meaningful conclusions. The more significant hierarchical structure of road network, the lower the total travel time and the greater the absolute value of its elasticity on the diffusion parameter(θ). The enhancement of determinacy of the real road network that has relatively strong randomness will save more travel time. The road network installed with VMS is more slightly affected by dispersion parameter when the performance is measured by total travel time.

Key words: Transportation planning and management, cross-nested Logit, stochastic user equilibrium, hierarchical road network, route choice behavior, VMS