道路环形交叉口机动车冲突风险区识别模型研究

Roundabout Motor Vehicle Conflict Risk Identification Model

为定量识别城市非信控环形交叉口区域内的机动车冲突风险易发生点,降低环形交叉口的事故发生率,本文构建针对非信控环形交叉口机动车冲突风险识别模型。首先,利用无人机采集高精度、连续的多车辆轨迹视频,结合Kinovea视频运动分析软件实现运行车辆状态识别与跟踪,并记录车辆每一帧的运动数据;其次,基于交通冲突识别指标TTC(Time to Collision),提出适应环形交叉口道路线形特征的车辆TTC计算方法,并使用累计频率法确定严重、一般和轻微冲突的阈值分别为1.2,2.8,4.4 s;最后,通过绘制高峰和平峰交通冲突空间异步图,并结合交通冲突数和严重冲突率,对环形交叉口的36个子区段进行交通冲突风险等级评定。研究结果显示:在高峰时段,某一子区段的平均交通冲突发生次数约为15次,严重冲突率为17.45%;在平峰时段,某一子区段的平均交通冲突发生次数约为8次,严重冲突率为8.28%。重度风险区域在高峰时段占比达到50%,而在平峰时段为8.33%,这些重度风险区域主要集中在交织区段。因此,环形交叉口在高峰时段且位于交织区段的情况更易发生交通事故。本文研究成果有助于交通管理部门了解环形交叉口在不同时段和区段上的交通冲突情况和特征,以便采取相应的预警和管理措施。

To quantitatively identify the vulnerable points of motor vehicle conflict risk in the area of urban roundabouts and reduce the traffic accidents,this paper proposes a model to identify motor vehicle conflict risk at urban roundabouts.First,high-precision and continuous multi vehicle trajectory videos are collected using drones,and combined with Kinovea video motion analysis software to achieve vehicle state recognition and tracking,and record the motion data of each frame of the vehicle.Then,based on the traffic conflict recognition indicator TTC(Time to Collision),a vehicle TTC calculation method was proposed,which adapted to the linear characteristics of the roundabout.The cumulative frequency method was used to determine the thresholds for serious,general,and minor conflicts as 1.2 seconds,2.8 seconds,and 4.4 seconds,respectively.By drawing an asynchronous map of peak and peak traffic conflict space,and combining the number of traffic conflicts and severe conflict rates,the risk level of traffic conflict in 36 sub sections of the roundabout is evaluated.The research results show that during peak hours,the average number of traffic conflicts in a certain sub segment is about 15,with a severe conflict rate of 17.45%.During peak hours,the average number of traffic conflicts in a certain sub section is about 8,with a severe conflict rate of 8.28%.The proportion of high-risk areas reaches 50%during peak hours,while it is 8.33%during peak hours.These high-risk areas are mainly concentrated in weaving sections.Therefore,roundabouts are more prone to traffic accidents during peak hours and are located in weaving sections.The results of this study are helpful for traffic management departments to understand the traffic conflicts and characteristics of roundabout at different time periods and sections,to take corresponding warning and management measures.