同向竖曲线车线共振及降振措施  

Car Line Resonance and Vibration Reduction of Synclastic Vertical Curve

作　　者：杜永平 张逸 鲁雯卓 DU Yongping;ZHANG Yi;LU Wenzhuo

机构地区：[1]同济大学建筑设计研究院(集团)有限公司,上海200092

出　　处：《上海公路》2023年第3期14-22,45,M0003,M0004,共12页Shanghai Highways

摘　　要：为提升旧路改造工程中常用的线形同向竖曲线线形质量,在受力分析的基础上,将线形参数、平整度纳入“人-车-路”动力学模型。以半径2000 m、5000 m同向凹曲线为算例,采用Newmark-β法编制程序计算,从运动、力学角度,分析表明线形变化是引起车线共振的形成原因,并采用加速度峰值等振动指标和汽车振动感知标准,总结了车线共振特征结构,确定了线形内的共振区和稳定区范围。对竖曲线形态、行驶方向以及同向竖曲线半径和间距等影响因素进行计算分析,找出同向竖曲线产生较强车线共振的二种线形工况:不对称竖曲线各半径的曲线小度小于3 s行程时,将形成耦合共振区;同向竖曲线间直坡长度小于3 s行程时,也产生耦合共振区。总结计算分析成果,确定同向竖曲线车线共振的主要影响因素是竖曲线半径、半径差以及短的曲线长度和曲线间直坡长度,这也是影响行车服务性能的主要因素。从降低车线共振角度,采用七次抛物线作为缓和竖曲线,同向竖曲线增设缓和竖曲线降振效果显著,加速度振动峰值、均方根下降到原来的3.5%以内,远小于振动感知阈值。考查纵断面线形与平整度耦合振动工况,增设缓和竖曲线,对比直坡状态下的人体加速度均方根接近1,基本消除了线形对行车舒适性的影响,接近“人-车-路”系统要求的理想平面状态。In order to improve the linear quality of homogeneous vertical curves,which are commonly used in old road reconstruction projects,the linear parameters and flatness are incorporated into the"human-vehicle-road"dynamics model on the basis of force analysis.Taking the same direction concave curve with radius of 2000 m and 5000 m as an example,the Newmark-βmethod is used to compile the program from the perspective of motion and mechanics,the analysis shows that the road alignment change is the cause of vehicle resonance.Using the vibration indexes such as the peak acceleration and vehicle vibration perception standards,the characteristic structure of the car line resonance is summarised,and the range of resonance and stability zones within the line is determined.Two strong resonance working conditions are identified by examining the factors affecting the resonance,such as the vertical curve shape,driving direction,radius,and spacing of the compound vertical curves.Coupled resonance zone will be formed on an asymmetric vertical curve while the curve length is less than 3 seconds of travel distance.Additionally,the coupled resonance zone will also be formed when the length of the straight section between synclastic vertical curves is less than 3 seconds of travel distance.Consequently,the main factors affecting the roadway resonance and driving performance are the radius of vertical curve,the radius difference,length of the shorter curve,and the straight slope length between the curves.To reduce the roadway resonance,a seven-degree parabolic curve is used as transition curve.This results in a significant reduction in acceleration peak.The root mean square of peak vibration acceleration decrease to less than 3.5%of the original value,which is below the vibration perception threshold.Furthermore,the road pavement roughness is examined in conjunction with the vertical curve.By introducing a transition curve instead of using a straight segment,the root mean square of the human body acceleration under this condition is cl

关 键 词：道路工程 同向竖曲线 动力学 车线共振 行车舒适性 

分 类 号：U418.8[交通运输工程—道路与铁道工程]