冰雪道路环境下交通流微观仿真及事故率研究

Microscopic simulation and accident probability of traffic flow in ice and snow environment

为给冰雪下交通管控提供更加科学的决策支持以提高行车安全性,在考虑驾驶员特性的基础上,分析车辆受力及驾驶行为,讨论可能发生的追尾和侧滑事故,建立冰雪下单向双车道可能交通事故的元胞自动机模型(CAM);通过仿真校验该模型,并分析冰雪下流量-密度特性及管控措施下的事故概率。结果表明:应根据冰雪路面类型及道路几何线形采取不同措施以降低事故概率,光滑冰膜水平路面使用融雪剂并限速可将事故概率降低41. 02%,其他冰雪下水平路面采用分类限速可将事故概率降低34. 20%以上;纵坡采取融雪剂结合分类限速可有效降低事故概率;光滑冰膜下纵坡需安装防滑链或使用冬季轮胎以提高行车安全性。

In order to provide more scientific decision support for traffic control so as to improve driving safety under ice and snow conditions,vehicle force and driving behaviors were analyzed,and possible rearend collision and side-slip accidents were discussed based on drivers’ characteristics. Then,a CAM of twolane one-way possible traffic accidents under ice and snow conditions was established. Finally,through traffic simulation,this model was validated,and flow-density characteristics and accident probability with control measures were analyzed. The results indicate that different measures should be taken to reduce accident probability according to specific ice and snow conditions and road geometry. It can be reduced by 41. 02% through using deicing salt and setting speed limit on horizontal road covered with smooth ice film,and more than 34. 20% if different speed limits were set on horizontal road in other ice and snow environment. It can also be reduced effectively by using deicing salt combined with classified speedlimiting measures on longitudinal slope road. And anti-skid chains or winter tires should be installed for vehicles on longitudinal slope road under smooth ice film so as to improve driving safety.