基于交通流特性的高速公路出口匝道与地面道路衔接部安全几何设计

摘要

Off ramp-street terminal is a key transfer node for the traffic flow from freeway to the street.An appropriate safety geometric design method of off-ramp-street terminal is very significant for improving the freeway off ramp performance,capacity and safety.Based on investigations,some terminal traffic flow characteristics were analyzed from the following aspects:traffic flow characteristics,vehicle speed,traffic flow composition and so on,in order to identify the difference between the terminal and common intersections.Then,the terminal geometric design method was demonstrated in site selection of a terminal and the key points' safety geometric design.Last,the research result of this paper was applied to a planning project of a off-ramp-street terminal between Fen-jun freeway and 340 provincial highway in Shanxi Province as an example.It was proved that the presented method was practicable and applicable and could be reffered for safety geometric design of an off-ramp-street terminal.%高速公路出口匝道与地面道路衔接部是高速公路与地面道路交通流转换的重要节点,研究其安全几何设计方法,对改善高速公路匝道出口区域内的交通流通行效率和交通安全具有重要的意义.本文在现场调研的基础上,分析了衔接部的交通流特性,明确了衔接部的交通流性质、车辆行驶速度、交通组成等方面的特点;然后,从衔接部的选位、安全几何设计的要点方面提出了衔接部的安全几何设计方法;最后,以山西省汾军高速公路出口匝道与340省道衔接部为例,进行了衔接部的安全几何实例分析.研究表明,本文提出的衔接部安全几何设计方法是一种简单实用、可操作性强的交通设计方法,它对我国现阶段衔接部的交通安全设计具有一定的借鉴意义.