互通式立交主线同侧相邻入口最小净距研究  

Study on Minimum Net Distance between Adjacent Entrances on Same Side of Interchange Mainline

作　　者：李兴华 李翔 潘兵宏[3] LI Xing-hua;LI Xiang;PAN Bing-hong(China Highway Engineering Consulting Corporation,Beijing 100089,China;Shandong Provincial Communications Planning and Design Institute Group Co.,Ltd.,Jinan Shandong 250101,China;School of Highway,Chang'an University,Xi'an Shaanxi 710064,China)

机构地区：[1]中国公路工程咨询集团有限公司,北京100089 [2]山东省交通规划设计院集团有限公司,山东济南250101 [3]长安大学公路学院,陕西西安710064

出　　处：《公路交通科技》2023年第4期216-227,共12页Journal of Highway and Transportation Research and Development

基　　金：中交科技基金项目[2018]05号。

摘　　要：互通式立交主线同侧相邻入口净距是影响车辆通行效率与安全的关键因素,但规范中对相邻出入口净距的规定未区分相邻入口和出口的异同,且未考虑匝道设计速度及车道数,所规定的相邻入口最小净距存在不合理的地方。以互通式立交主线同侧相邻入口最小净距为研究对象,通过分析此区域车辆运行特性,确定了相邻入口最小净距的计算模型是由加速车道及合流安全视距构成。首先,调查合流区数据,得到了符合实际的加速车道特征断面速度,以确定提速段长度。基于3阶爱尔朗分布,确定了等待段长度,同时考虑车辆换道需求,采用双曲正切换道模型确定了渐变段长度,由提速段、等待段以及渐变段共同组成加速车道长度。其次,通过对相邻入口处驾驶员视距的研究,分析了反应距离、决策距离、换道距离以及减速距离,得到合流安全视距。最后,组合加速车道长度和合流安全视距,提出了不同主线、匝道设计速度和匝道车道数下的相邻入口最小净距建议值。结果表明:主线与匝道的设计速度差越大,所需要的相邻入口净距越大;下游入口匝道为双车道时,规范中规定的最小净距值难以满足要求;主线设计速度较高或主线与匝道设计速度差值过大时,若采用规范中的规定值作为相邻入口净距,则无法满足车辆安全运行的要求。The minimum net distance between the adjacent entrances on the same side of interchange mainline is a key factor affecting the efficiency and safety of vehicle operation,while the specified net distance between adjacent accesses in the specification has not distinguished the similarities and differences between adjacent entrance and exit,and has not considered the design speed and lane number of ramp,therefore,the specified minimum net distance between adjacent entrances is unreasonable.Taking the minimum net distance between the adjacent entrances on the same side of interchange mainline for the research object,by analyzing the operation characteristics of vehicles in this area,it is determined that the calculation model of the minimum clear distance between adjacent entrances is composed of the acceleration lane and the merging safety sight distance.First,the data of merging area are investigated to obtain the realistic speed at characteristic section of acceleration lane and determine the length of acceleration section.Based on 3-stage Erlang distribution,the length of waiting section is determined.Simultaneously,considering the demand of vehicle lane changing,the length of transition section is determined by adopting hyperbolic tangent lane changing model.The length of accelerating lane is composed of accelerating section,waiting section and transition section.Second,by researching the sight range of driver at adjacent entrance,the reaction distance,decision distance,lane changing distance and deceleration distance are analyzed,and the merging safety sight distance is obtained.Finally,by combining the acceleration lane length and merging safe sight distance,the suggested minimum net distances between adjacent entrances under different mainlines,ramp design speeds and numbers of ramp lanes are proposed.The result shows that(1)the larger the design speed difference between mainline and ramp,the larger the net distance between adjacent entrances;(2)when the downstream on-ramp is two-lane,the minimum net distance

关 键 词：交通工程 相邻入口最小净距 长度建模 加速车道 合流视距 

分 类 号：U412.352.12[交通运输工程—道路与铁道工程]