高速公路客货混行交通流元胞传输模型

Cell transmission model for mixed traffic flow of cars and trucks on highways

针对客货混行引发的交通流稳定性下降、交通安全风险增加以及运行效率降低等问题,构建一个多车道客货混行交通流元胞传输模型,从宏观角度研究不同货车渗透率下的高速公路客货混行交通流特性.首先,利用微观车辆跟驰模型,分析均质小汽车和货车交通流的基本图特征,提出不同货车渗透率下的客货混行交通流基本图模型.然后,采用具体参数表征换道、有限加速度造成的道路交通容量下降效应,刻画客货混行交通流中货车对直行和换道流量的影响,采用Logit模型计算多因素影响下的换道交通流量,构建多车道客货混行交通流元胞传输模型.最后,通过高速公路多场景仿真实验验证模型的有效性.研究结果表明:所提出的模型可准确模拟高速公路上的客货混行交通流演变过程;货车渗透率是影响混行交通运行的关键因素,在交通事件导致车道数减少时,货车渗透率超过0.6会导致交通拥堵难以消散.研究成果可为高速公路客货混行交通流特性研究提供分析工具,为客货混行下的交通管理和疏导策略制定提供理论方法.

Addressing the issues of decreased traffic flow stability,increased traffic safety risks,and reduced operational efficiency caused by mixed passenger and freight traffic,this paper constructs a multi-lane mixed passenger and freight traffic flow cell transmission model to study the characteristics of highway mixed traffic under different truck penetration rates from a macroscopic perspective.Initially,utilizing microscopic car-following models,the fundamental diagram characteristics of homogeneous passenger car and truck traffic flows are analyzed,and a fundamental diagram model of mixed traffic flow under different truck penetration rates is proposed.Subsequently,specific parameters are employed to characterize the effects of lane-changing and limited acceleration on the reduction of road traffic capacity,depicting the impact of trucks on straight and lane-changing traffic flow in mixed traffic.The Logit model is used to calculate lane-changing traffic volume under the influence of multiple factors,thus constructing a cell transmission model of multi-lane mixed passenger and freight traffic flow.Finally,the model's effectiveness is verified through multi-scenario highway simulation experiments.The research results show that the proposed model can accurately simulate the evolution of mixed traffic flow on highways;truck penetration rate is a critical factor affecting mixed traffic operations,and when traffic incidents reduce the number of lanes,a truck penetration rate exceeding 0.6 leads to persistent traffic congestion.The study provides analytical tools for researching mixed passenger and freight traffic flow characteristics and offers theoretical methods for traffic management and guidance strategy formulation under mixed traffic conditions.