高速公路交通流元胞自动机建模及大货车的影响分析

Modeling with cellular automata and influence analysis of trucks on freeway traffic flow

在分析国内4车道高速公路交通特性的基础上,根据动机将换道分为无倾向型和有倾向型,描述法定换道规则,建立相应的元胞自动机模型,用实测交通流参数标定和验证模型。研究结果表明:随着大货车比率增大,大货车对快车道的占用增多,小客车速度降低,上述变化在大货车比率小于0.25时更显著并与密度相关;当大货车比率很小时,随着大货车动力性能降低,小客车速度降低,换道和冲突增多,这些变化在中密度区最显著;在临界密度附近,随着大货车比率变化,可随机观察到典型的移动瓶颈和偏析效应。

Based on the analysis of traffic characteristics of four-lane freeways in China,lane-changing types were classified into tendentious and non-tendentious ones according to the motivation,and the legal lane-changing rules were described concisely.The corresponding cellular automaton model was proposed,which was calibrated and verified with the measured traffic flow parameters.The results show that,with the increase of the truck ratio,the fast lane occupation by trucks increases and the speed of cars decreases.The above changes are more significant when the truck ratio is less than0.25and is correlated with the density.When the truck ratio is very small,as the truck power performance degrades,the speed of cars decreases and the lane-changing rate and conflict rate of cars increase.The above changes are most significant when the density is in the medium range.When it is near the critical density,the typical moving bottlenecks and segregation effects can be observed at random when the truck ratio changes.