Asymmetric Behavior and Traffic Flow Characteristics of Expressway Merging Area in China

  • Weihua Zhang
  • Siping Wei
  • Changsheng Wang Hefei University of Technology
  • Meng Qiu Hefei University of Technology
Keywords: Expressway; Merging area; Asymmetric behavior; Traffic hysteresis; Capacity


The urban expressway confluence area is selected as the research object. Through video aerial photography, image processing and artificial auxiliary technology to obtain high precision trajectory data. Based on the measured data, the driver response mode is divided into multiple sub-models from the macro and micro levels. Based on the measurement of driver type, asymmetric characteristic index and driver response mode, the type and distribution of traffic delay and the influence of asymmetric behavior on the traffic capacity of confluence area are further revealed. The results show that the radical, conservative and ordinary drivers mainly adopt non-decreasing mode, concave mode 4-1 and convex mode 2-1 respectively in the process of oscillation disturbance.The traffic delay caused by the driver ' s asymmetric behavior in the confluence area of the expressway is generally positive, and the average reaction time of the driver is larger than that of the equilibrium state. And asymmetric behavior leads to the average decrease of bottleneck outflow rate by about 7 %, which leads to the increase of delay and the decrease of traffic capacity.


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How to Cite
Zhang W, Wei S, Wang C, Qiu M. Asymmetric Behavior and Traffic Flow Characteristics of Expressway Merging Area in China. Promet [Internet]. 2023Feb.13 [cited 2023Dec.3];35(1):12-6. Available from: