双车道公路机动车交通行为安全评估模型

Safety Evaluation Model of Vehicle Behaviors on Two lane Highway

摘要:

为了客观评价双车道公路机动车交通行为安全性，应用神经网络与模糊评判方法，结合空间向量理论，构建了安全评估模型.首先根据国内外机动车交通行为安全性的相关研究成果，选用超速指数、平均车头时距与安全超车视距分别作为自由流超速行为、跟驰行为与超车行为3类机动车交通行为安全性状态判别指标，并提出各指标安全性界定标准.然后利用3层神经网络模型建立了双车道公路运行环境下7个主要指标与机动车交通行为的关系模型，通过部分实测路段数据验证了模型的可靠性；以模糊评判方法为基础，建立了机动车交通行为安全性判别指标的隶属函数，基于评价结果对3类机动车交通行为安全性等级进行了划分；并结合空间向量理论提出综合评价向量以表征机动车交通行为综合安全性.理论分析和实例表明该评估模型可为双车道公路机动车交通行为安全性评估提供一种较为可行的方法.

Abstract:

A safety evaluation model was established based on neural networks, fuzzy evaluation method and space vector theory, for an objective evaluation of vehicle behaviors safety on two lane highway. First, according to the previous research, overspeed index, the average headway and safety overtaking sight distance were selected as discriminant indexes of safety state about the three types: overspeed behavior of free flow, following behavior and passing behavior， respectively, and safety level were determined for each indicator. Then, the relationship model between the seven major indicators of the operating environment on two lane highway and vehicle behaviors characteristics was established by three layer neural network model and its reliability was verified with the measured sections data. The membership function about the discrimination indexes of safety state was established by fuzzy evaluation method and the safety level of the three types of vehicle behaviors were divided. Vehicle behaviors comprehensive safety was characterized by comprehensive evaluation vector which was proposed by space vector theory. The evaluation model is illustrated by a case study which will serve a reliable method to evaluate vehicle behaviors safety on two lane highway.