高速铁路无砟轨道斜拉桥刚度理论分析与设计参数研究  

Stiffness and structural parameters of high-speed railway cable-stayed bridge with ballastless track

作　　者：孙宗磊 郭辉 向律楷[3] SUN Zonglei;GUO Hui;XIANG Lükai(School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;Railway Engineering Research Institute,China Academy of Railway Sciences Corporation Limited,Beijing 100081,China;China Railway Eryuan Engineering Group Co.,Ltd.,Chengdu 610031,China)

机构地区：[1]西南交通大学土木工程学院,四川成都610031 [2]中国铁道科学研究院集团有限公司铁道建筑研究所,北京100081 [3]中铁二院工程集团有限责任公司,四川成都610031

出　　处：《铁道科学与工程学报》2024年第5期1726-1736,共11页Journal of Railway Science and Engineering

基　　金：国家重点研发计划(2022YFB2602900);中国国家铁路集团有限公司科技研究开发计划重大课题(K2021G020);中国铁道科学研究院院基金重大课题(2021YJ084);国家自然科学基金高铁联合基金资助项目(U1934207)。

摘　　要：为研究高速铁路无砟轨道斜拉桥的刚度特征以及合理结构设计参数,采用理论公式推导、数值分析等手段,得到结构设计参数刚度影响解析公式及其影响规律,用于指导桥梁设计。首先引入索梁活载刚度比的概念,通过建立斜拉桥主梁多点支承连续梁的三弯矩方程得到主梁刚度,通过考虑主塔变形和拉索伸长量得到斜拉索等效刚度,进而给出斜拉桥整体刚度、索梁活载刚度比和主梁跨中挠度的理论公式,并基于理论公式得出主梁惯性矩、斜拉索倾角、塔高以及拉索面积对斜拉桥整体刚度的影响。以广湛铁路东平水道特大桥主桥(67.5+60+60+350+60+60+67.5)m钢箱混合组合梁无砟轨道斜拉桥为例,通过对比跨中活载位移理论解与数值解验证本文理论公式的准确性,进而采用理论公式分析结构设计参数对桥梁刚度的影响。研究结果表明:随拉索倾角增大或者塔高增加,主梁的跨中位移先减小后增大,索梁活载刚度比先增大再减小,拉索倾角为29.2°~73.9°时主梁跨中位移达到最小值36.4 cm,此时索梁活载刚度比为15.4。随着主梁的梁高增加,主梁跨中位移减小,索梁活载刚度比减小,但是减小幅度较为缓慢。拉索面积增大,主梁跨中活载位移减小,索梁活载刚度比增加。提出了桥梁合理梁高、塔高和斜拉索规格及拉索面积。桥梁结构静动力检算、桥上轨道静态高低不平顺验算以及无砟轨道受力与层间压缩量等检算结果均表明,该桥具有良好的安全性和行车平稳性。In order to study the stiffness characteristics and proper structural parameters of high-speed railway cable-stayed bridge with ballastless track,theoretical analysis and numerical simulation were carried out.Analytic formulae were obtained to calculate the influence of structural parameters on stiffness.Firstly,concept of cable beam stiffness ratio was proposed to analyze the stiffness characteristics.Then stiffness expression of main beam was derived from three-moment equation which the beam of cable-stayed bridge was equivalent to multi-support continuous beam.Equivalent stiffness expression of stayed-cable was obtained after considering the pylon deformation and elongation of stayed-cable.And the theoretical formulae were deduced including overall stiffness of cable-stayed bridge,cable beam stiffness ratio,and vertical deflection at mid-span.The influence of design parameters on cable-stay bridge overall stiffness was calculated mainly considering moment of inertia of main beam,inclined angle of stayed-cable,pylon height,and the stayed-cable cross sectional area.A steelconcrete hybrid composite box beam cable-stayed bridge,crossing the Dongping Waterway in GuangzhouZhanjiang Railway,was analyzed as a practical example with span arrangement of(67.5+60+60+350+60+60+67.5)m.Firstly,the accuracy of the proposed theoretical formulae was verified through comparison between the theoretical solution and numerical result of deflection at mid-span under live-load.Then the influence of structural parameters on bridge stiffness was analyzed.Results show that the displacement at the mid-span of main beam decreases firstly with increase of cable inclination or pylon height,and then increases.The cable beam stiffness ratio increases firstly,and then decreases.When the cable inclination is from 29.2°to 73.9°,the displacement at mid-span of main beam reaches the minimum value of 36.4cm and the cable beam stiffness ratio is 15.3.With the increase of the beam height,the mid-span deflection of the main beam decreases,and the ca

关 键 词：高速铁路 斜拉桥 混合组合梁 索梁活载刚度比 静力分析 车桥耦合动力分析 轨道静态高低不平顺 

分 类 号：U24[交通运输工程—道路与铁道工程]