Abstract: This paper investigates the overtaking maneuver of two-lane highways in mountainous areas under mixed traffic flow conditions and identifies the relationship between key variables and the duration of overtaking. Taking a typical two-lane mountainous highway in Yunnan Province as an example, this paper uses an unmanned aerial vehicle to acquire video data of overtaking behaviors and extracts the vehicle trajectories. The variables of overtaking maneuver is constructed to obtain the overtaking characteristics of two-lane mountainous highways. The overtaking duration model is established based on survival analysis to determine the key variables and then analyze the quantitative relationship between the key variables and the overtaking duration. The results show that under the mixed traffic flow conditions, the average overtaking duration of the two-lane highway in the mountainous area is 10.3 s, and the average overtaking distance is 201.3 m, which is caused by the combined effect of drivers' driving style, high driving speed, and complex traffic flow conditions. The Log-logistic Accelerated Failure Time model has the best fitting effect on the duration of overtaking. The AIC and BIC are 272.989 and 265.650, respectively. The inflection point of the hazard function is about 13 s, indicating that the possibility of overtaking ending before 13 s is the largest. The key variables are the overtaking distance, the initial speed difference, maximum lateral distance, the oncoming traffic, the length of the overtaken vehicle, and the type of the overtaking vehicle. The variables with the greatest influence are the type of overtaking vehicle and the oncoming traffic . When the overtaking vehicle is a truck, the overtaking duration increases by 22.9%. When there is an oncoming vehicle, the overtaking duration is reduced by 17.8%.

Key words: traffic engineering, overtaking maneuvers duration, survival analysis, mountainous two-lane highways; mixed traffic flow

摘要： 为研究混合交通流条件下山区双车道公路超车行为，确定关键影响因素与超车持续时间的关系。以云南省典型山区双车道公路为例，利用无人机采集超车行为视频数据，提取参与超车行为的机动车轨迹，构建超车行为变量指标体系，分析山区双车道公路超车行为特性；建立基于生存分析的山区双车道公路超车持续时间模型，确定影响超车持续的关键协变量，并分析关键协变量与超车持续时间的定量关系。结果表明：混合交通流条件下，山区双车道公路平均超车持续时间为10.3 s，平均超车距离为201.3 m，由驾驶员的驾驶风格、较高的行驶速度及复杂的交通流条件共同作用所致；Log-logistic 加速失效时间模型对超车持续时间拟合效果最好，AIC和BIC分别为272.989和265.650，危险函数拐点约为13 s，说明超车行为在13 s前结束的可能性最大；影响超车持续时间的关键变量分别为超车距离和超车车辆与被超车车辆的初始速度差、最大横向距离、是否有对向车、被超车车辆长度和超车车辆类型，影响程度较大的协变量为超车车辆类型和是否有对向车，当超车车辆为货车时，超车持续时间增加了22.9%，当有对向车时，超车持续时间降低了17.8%。

关键词: 交通工程, 超车持续时间, 生存分析, 山区双车道公路, 混合交通流