基于安全风险的恶劣天气下高速公路建议车速确定方法

Determination of Freeway Recommended Speed Based on Safety Risk Under Adverse Weather Conditions

摘要:

为了提高恶劣天气下高速公路交通安全水平，实施更加科学有效的高速公路车速管理策略，提出了基于安全风险的恶劣天气下高速公路建议车速确定方法。综合考虑交通安全风险影响因素，基于贝叶斯Logistic回归建立交通风险评估模型，利用模糊C-均值聚类算法进行交通风险等级划分并得到了风险阈值。在此基础上提出了不同天气条件下安全车速的两步计算方法，即先根据交通风险分布，在风险小于阈值的交通流状态中选取车辆运行速度的第85 %位车速作为初定安全行驶车速，后利用停车视距原理进行修正，最终得到恶劣天气下高速公路建议车速。并以G15沈海高速（上海段）为例，展示了计算方法，给出了雾天不同能见度条件下高速公路建议车速取值。

Abstract:

To improve the safety of freeway traffic in adverse weather， a method for determining the freeway recommended speed under adverse weather based on safety risk is proposed. Considering the influencing factors of traffic safety risk， a traffic risk assessment model is established based on Bayesian logistic regression， while the fuzzy C-means clustering algorithm is used to classify the traffic risk and obtain the risk threshold. A two-step calculation method for safe vehicle speed under different weather conditions is proposed. Firstly， the 85 %th vehicle speed of the vehicle running speed in the traffic flow state where the risk is less than the threshold is selected as the initial safe driving speed. Then， the principle of parking line of sight is used to correct the speed， in order to obtain the final recommended speed of the freeway in adverse weather. Taking G15 Shenhai Expressway （Shanghai section） as an example， the recommended speed of the freeway under different visibility conditions in foggy days is given.