山区高速公路车辆速度特性与区间限速方法

Speed behavior of mountain expressway and determination method of interval speed limit

为了合理确定事故多发路段的区间测速值,以G5515张南高速事故多发路段(K556+200 m~K578+800 m)为例,提出了高速公路区间限速值的设置方法和工作流程.以该路段为对象,利用移动式测速系统和ETC龙门架分别获取了该路段小型车和大型车的瞬时速度和行程速度数据,明确了高速公路典型车型的运行特性和速度分布特征,并根据大样本速度数据,建立了基于速度特征值的区间限速阈值模型,且运用横向力系数对模型进行了检验.研究结果表明:小客车和小货车的速度分布非常接近,可归类为小型车;小型车的速度离散性高于大型车(大客车和大货车),超出公示限速值的比例也高于大型车;车辆运行速度值与平均速度V_(a)的修正值(V_(a)+8 km/h)具有极强的线性关系,因此可以将其作为高速公路区间限速值的设置依据.

To determine the interval speed limit values for accident-prone sections, taking the accident-prone section(K556+200 m—K578+800 m) of G5515 Zhangnan Expressway as an example, the method and workflow of setting interval speed limit of expressway were proposed. Taking this section as the object, the instantaneous speed and travel speed data of light-duty vehicles and full-size vehicles in this section were obtained by the mobile speed capture system and electronic toll collection(ETC) gantry, respectively, and the operation characteristics and speed distribution characteristics of typical vehicles were obtained. According to the large sample speed data, the interval speed limit threshold model based on the speed characteristic was established and tested by the sideway force coefficient. The results show that the speed distribution of passenger cars is very similar to the vans, so the two vehicle types can be classified as small vehicles. The speed dispersion of small vehicles is higher than that of large vehicles(buses and trucks), and the proportion of exceeding the posted speed limit is also higher than that of large vehicles. The operating speed has a strong linear relationship with the corrected value of average speed(V_(a)+8 km/h), so the two parameters can be used as the setting basis of the interval speed limit value of expressway.