高速公路拥堵下的分级限速控制策略
余雪1，2，凤鹏飞1，3，4，段萌萌1，3，4
1.安徽三联学院智慧交通现代产业学院，安徽 合肥 230601；
2.山东交通学院交通与物流工程学院，山东 济南 250357；
3.国家车辆驾驶安全工程技术研究中心，安徽 合肥 230601；
4.安徽省普通高校交通信息与安全重点实验室，安徽 合肥 230601
摘要：为缓解高速公路交通事故后的拥堵问题，采用软件VISSIM模拟高速公路发生交通事故前、后的交通流状态，获取非拥堵状态和拥堵状态的交通流数据，分别采用Greenshields模型和Greenberg模型拟合非拥堵状态和拥堵状态的车流速度-密度关系曲线，构建高速公路交通拥堵持续时间预测模型，通过该模型计算不同上游到达流量和不同交通事故阻塞时间下交通拥堵持续时间，并通过仿真验证模型的准确性。将高速公路交通拥堵持续时间预测模型与遗传算法相结合，求解车辆到达拥堵路段排队队尾位置时的车速，以此确定参考限速，针对拥堵情况提出分级限速控制策略，从事故上游路段对车辆实施多次逐级限速，使车速平稳减小，限制拥堵区的车辆数。结果表明：不同上游到达流量和不同阻塞时间下交通拥堵持续时间计算结果和仿真结果的平均绝对百分比误差为14.37%，交通拥堵持续时间预测模型准确性较高，可用来计算高速公路事故发生后的拥堵持续时间；采取分级限速控制策略后，上游到达流量为3 000 veh/h时，平均排队长度从2 141 m降至1 340 m，拥堵路段平均车流速度从28.7 km/h增至36.0 km/h，分级限速控制策略可有效缓解高速公路交通事故后的拥堵状况。
关键词：高速公路；拥堵持续时间；分级限速；仿真
Graded speed limit control strategy under highway congestion
YU Xue1,2, FENG Pengfei1,3,4, DUAN Mengmeng1,3,4
1.College of Intelligent Transportation Modern Industry, Anhui Sanlian University, Hefei 230601, China;
2.School of Transportation and Logistics Engineering, Shandong Jiaotong University, Jinan 250357, China;
3. National Engineering Research Center for Vehicle Driving Safety, Hefei 230601, China;
4. Anhui Provincial Key Laboratory of Traffic Information and Safety in General Universities, Hefei 230601, China
Abstract: To alleviate occasional congestion problems after highway traffic accidents, the traffic flow states before and after accidents are simulated using the software VISSIM, and traffic flow data for non-congested and congested states are obtained. The Greenshields model and the Greenberg model are used to fit the speed-density relationship curves for non-congested and congested states, respectively, and a highway traffic congestion duration prediction model is constructed. Through the model, the congestion duration under different upstream arrival flows and different traffic accident blockage times is calculated, and the model′s accuracy is verified through simulation. The highway traffic congestion duration prediction model is combined with a genetic algorithm to solve the vehicle speed when vehicles arrive at the queue tail position of the congested section, thereby determining the optimal speed limit. A graded speed limit control strategy is proposed for congestion situations, where multiple gradual speed limits are implemented for vehicles from the upstream section of the accident, allowing the speed to decrease smoothly and restricting the number of vehicles in the congested area. The results show that the mean absolute percentage error between the calculated and simulated results of congestion duration under different upstream arrival flows and different blockage times is 14.37%, indicating that the traffic congestion duration prediction model has high accuracy and can be used to calculate the congestion duration after highway accidents. After implementing the graded speed limit control strategy, when the upstream arrival flow is 3 000 veh/h, the average queue length decreases from 2 141 m to 1 340 m, and the average traffic flow speed in the congested section increases from 28.7 km/h to 36.0 km/h, demonstrating that the graded speed limit control strategy can effectively alleviate highway congestion.
Keywords: highway; congestion duration; graded speed limit; simulation
