Abstract: In order to describe the stochastic road network with time-varying congestion degree, a novel variable cell transmission model is proposed. The model is based on each lane of the road network. Each lane is divided into lane cell and intersection cell. The two cells of same lane, one falling and the other one rising, interact. Lane cell model and intersection cell model are established respectively. The average speed of lane cell and congestion degree of the intersection cell are used as the model output. Congestion degree of each lane cell and intersection cell are judged based on the model output. To describe the stochastic characterization of the road network, model and simulation data are set to increase the stochastic characterization of the road network. The simulation results indicate that：congestion degree of each lane cell and intersection cell are time-varying in a road network, and the model can describe stochastic characterization of a road network.

Key words: traffic engineering, stochastic road network, time-varying congestion degree, variable cell transmission model, simulation and verification of model

摘要： 为了描述拥堵程度时变的随机路网，提出了一种新的可变元胞传输模型。该模型是以路网各车道为基础，将各车道分为车道元胞和交叉口元胞。同一车道的两个元胞“此消彼长”，相互作用。分别建立两种元胞模型，将车道元胞的平均车速和交叉口元胞拥堵程度作为模型输出。根据模型输出结果判断各车道元胞和交叉口元胞的拥堵程度。为描述路网的随机特性，建模及仿真数据的设置增加了路网的随机性。仿真结果表明：路网中各车道元胞和各交叉口元胞的拥堵程度时变，提出的可变元胞传输模型能够描述路网的随机性。

关键词: 交通工程, 随机路网, 拥堵程度时变, 可变元胞传输模型, 模型仿真验证