基于终点的用户均衡交通分配模型求解算法

用户均衡分配模型是更接近实际交通状态的分配模型,它是建立在出行者总选择起迄点间交通时间最短的路径作为出行路线的行为假设基础上的。分析基于终点的用户均衡交通分配模型,指出该模型与基于路径均衡配流模型是等价的,在选择美国BPR路阻函数后,模型可以转化为带线性约束的非线性规划问题,并给出模型的矩阵表示。对这类问题,采用简便实用的仿射尺度算法求解,给出算法的基本思想及详细的实现过程。仿真结果显示,所得最优解满足Wardrop第一准则,表明该算法是有效的,可用于大型路网的配流计算。

Algorithm for User Equilibrium Traffic Assignment Model Based on Destination

User equilibrium assignment model is the one that is closer to actual traffic situation.It is established on the fact that the travellers are apt to choose the shortest paths as travel routes between OD(origin destination).The paper analyzes user equilibrium traffic assignment model based on destination,and points out that the model and traffic assignment model based on path are equivalent.By using BPR link travel time function,the model can be translated into nonlinear programming problem with linear constraints and represented in matrix form.To solve the problem,affine scaling algorithm is adopted and the general idea and detailed implementation process of the algorithm are given.Simulation demonstrates that the optimal solution observes Wardrop first principle and the method is effective,so it is suitable to solve the traffic assignment problem in large scale road network.