基于事故数据与安全服务水平的高速公路路段安全性评价方法

分析了高速公路路段的基本划分方法, 提出了基于事故点集疏程度的动态聚类路段不定长划分方法, 依据负二项分布标定了事故预测模型, 提出了基于负二项分布的路段安全性评价方法。引入交通安全服务的水平概念, 确定了分级标准, 提出了基于安全服务水平的路段安全性评价方法, 并进行了实例验证。验证结果表明: 分别利用2种方法对京珠高速公路109个路段进行安全性评价时, 57.8%的路段评价结果相同; 利用基于负二项分布的安全性评价方法评价的安全状况良好、较好、较差、差的路段分别为5、63、36、5个, 利用基于安全服务水平的安全性评价方法评价的结果分别为1、64、26、18个, 基于负二项分布的安全性评价方法评价的安全等级更符合实际高速公路安全状况。基于负二项分布的安全性评价方法考虑了交通量与线形条件, 适用于线形条件复杂的高速公路, 基于安全服务水平的安全性评价方法考虑了交通量与事故次数, 更适合于线形条件较好的高速公路。

Safety evaluation method of freeway segment based on accident data and safety service level

The basic division method of freeway segment was analyzed, the unequal-length division method of dynamic clustering segment based on the concentration and dispersion degrees of accident point was put forward.The accident prediction model was calibrated based on negative binomial distribution, the safety evaluation method of freeway segment based on negative binomial distribution was proposed.The concept of safety service level was introduced, the classification standard was determined, the safety evaluation method of freeway segment based on safety service level was proposed, and the example verification was carried out.Verification result indicates that when the 109 segments of Jingzhu Freeway are evaluated by using the two methods respectively, the 57.8% of segments have the same results, the segment amounts of safety conditions in great, good, normal, poor are 5, 63, 36 and 5 respectively by using the safety evaluation method based on negative binomial distribution, while the segment amounts of safety conditions in great, good, normal, poor are 1, 64, 26 and 18 respectively by using the safety evaluation method bassed on safety service level.The evaluation result of safety evaluationmethod based on negative binomial distribution is more in line with freeway actual safety situation.The safety evaluation method based on negative binomial distribution considers traffic volume and geometric alignment, and is more suitable for the freeway with complex geometric alignment conditions.The safety evaluation method based on safety service level considers traffic volume and accident frequency, and is more suitable for the freeway with better geometric alignment conditions..