高速公路改扩建期S型切换长度及限速值计算方法  

Calculation Method of S-type Switching Opening Length and Speed Limit Value during Expressway Reconstruction and Expansion

作　　者：李晓东 车思亮 何木 闫栋 宋浪 王少飞 LI Xiao-dong;CHE Si-liang;HE Mu;YAN dong;SONG Langg;WANG Shao-fei(Guangzhou Beierhuan Transportation Technology Co.Ltd.,Guangzhou 510030,China;National Engineering and Research Center for Mountainous Highways,Chongqing 400067,China;China Merchants Chongqing Communications Technology Research&Design Institute Co.Ltd.,Chongqing 400067,China)

机构地区：[1]广州市北二环交通科技有限公司,广州市510030 [2]国家山区公路工程技术研究中心,重庆市400067 [3]招商局重庆交通科研设计院有限公司,重庆市400067

出　　处：《公路》2025年第2期263-270,共8页Highway

基　　金：北二环高速公路改扩建期间精细化管控策略研究项目,项目编号BEH-2023-ZX-082;重庆市自然科学基金项目,项目编号CSTB2023NSCQ-MSX0387;重庆市技术创新与应用发展专项重点项目,项目编号CSTB2022TIAD-KPX0104。

摘　　要：为解决纵坡影响下高速公路不同改扩建模式不同S型切换样式开口长度合理设置问题,基于车辆在S型切换处因纵坡、横坡存在而形成的三维行驶轨迹特点,刻画车辆行驶过程中不产生横向侧滑的受力平衡关系,依托车辆受力平衡方程和三维行驶轨迹几何关系,构建S型切换开口长度通用理论计算方法,并给出了不同纵坡、横坡下的开口长度取值,发现本文方法计算的开口长度不小于规范方法,且最大差值达到了9.26 m,说明开口长度的计算不考虑纵坡的影响,其不满足行车安全要求。针对雨天、雪天等恶劣天气导致路面湿滑下摩擦系数降低的情况,推导S型切换限速值计算公式,实现恶劣天气动态限速管理,发现S型切换限速值随着路面摩擦系数的降低而降低,说明在雨雪天采用动态限速控制可保障行车安全。将研究成果应用到国内某高速公路改扩建工程,确保了该工程1处复杂道路环境导改点S型切换的合理设置。In order to solve the problem of reasonable setting of the opening length of different S-type switching styles under the influence of longitudinal slope in different reconstruction and expansion modes of expressways,based on the three-dimensional driving trajectory characteristics of vehicles at the S-type switching due to the existence of longitudinal slope and transverse slope,the force balance relationship without lateral sideslip during the driving process of vehicles is described in the paper.Relying on the force balance equation of vehicles and the geometric relationship of three-dimensional driving trajectory,a general theoretical calculation method is constructed for the opening length of S-type switching,and the opening length values under different longitudinal slope and transverse slope are provided.It is found that the opening length calculated by this method is not less than that calculated by the standard method,and the maximum difference reached 9.26 m,which indicates that the calculation of the opening length doesn't consider the influence of longitudinal slope and does not meet the requirements of driving safety.In view of the situation that the friction coefficient of the road under wet slippery conditions caused by rainy days,snow days and other severe weather,the calculation formula of the speed limit value of S-type switching is derived to realize the dynamic speed limit management in severe weather.It is found that the speed limit value of S-type switching decreases with the decrease of the road friction coefficient,which indicates that the dynamic speed limit control could guarantee the driving safety in rainy and snowy days.The research results are applied to a domestic expressway reconstruction and expansion project,which ensures the reasonable setting of the S-type switch at a complex environmental diversion point in the project.

关 键 词：交通工程 高速公路改扩建 S型切换段 开口长度 动态限速 

分 类 号：U491.4[交通运输工程—交通运输规划与管理]