高速铁路桥上设计震致轨道几何不平顺等效方法  

Equivalent method for designed earthquake-induced track geometric irregularities on high-speed railway bridges

作　　者：余建 周旺保[1,2] 蒋丽忠[1,2] 冯玉林 刘祥 YU Jian;ZHOU Wang-bao;JIANG Li-zhong;FENG Yu-lin;LIU Xiang(School of Civil Engineering,Central South University,Changsha 410075,Hunan,China;National Engineering Research Center of High-Speed Railway Construction Technology,Central South University,Changsha 410075,Hunan,China;School of Civil Engineering and Architecture,East China Jiaotong University,Nanchang 330013,Jiangxi,China;School of Civil Engineering,Fujian University of Technology,Fuzhou 350118,Fujian,China)

机构地区：[1]中南大学土木工程学院,湖南长沙410075 [2]中南大学高速铁路建造技术国家工程研究中心,湖南长沙410075 [3]华东交通大学土木建筑学院,江西南昌330013 [4]福建理工大学土木工程学院,福建福州350118

出　　处：《交通运输工程学报》2024年第3期110-123,共14页Journal of Traffic and Transportation Engineering

基　　金：国家自然科学基金项目(52078487);中南大学创新驱动计划项目(502501006)。

摘　　要：为解决考虑结构随机的设计震致轨道几何不平顺等效问题,建立了高速铁路轨道-桥梁系统的数值仿真模型,基于短时傅里叶变换和假设检验原理构造了设计震致轨道几何不平顺,建立了设计震致轨道几何不平顺的等效拟合模型和等效幅值反应谱,提出了考虑结构随机的等效幅值反应谱修正方法,结合震后实测轨道几何不平顺对设计震致轨道几何不平顺等效方法的合理性展开了评价。分析结果表明:在不同墩高条件下,采用正弦函数和一次函数的组合作为等效拟合模型可将设计震致轨道几何不平顺的拟合误差控制在10%以内;在设防地震和罕遇地震作用下,当修正系数分别取为3.0和1.5时,等效拟合模型与修正系数相乘得到的修正拟合模型可以满足随机结构的适用性需求;地震前后实测轨道几何不平顺形状和幅值均无明显差异,对应的横向车体加速度幅值误差小于5%,当地震强度较小时列车可正常运行,无需大幅度减速;与震后实测轨道几何不平顺相比,设计震致轨道几何不平顺使横向车体加速度幅值提升了近50%,基于设计震致轨道几何不平顺计算得到的震后行车速度阈值具有合理安全余量;建立的高速铁路桥上设计震致轨道几何不平顺等效方法可为高速铁路震后行车速度阈值确定与基于震后行车性能的抗震设计提供快速准确的手算方法。In order to solve the equivalent problem of designed earthquake-induced track geometric irregularities considering structural randomness,a numerical simulation model of high-speed railway track-bridge system was established.Based on the short-time Fourier transform and the hypothesis testing principle,designed earthquake-induced track geometric irregularities were constructed.The equivalent fitting models and equivalent amplitude response spectra of designed earthquake-induced track geometric irregularities were established.A method for correcting the equivalent amplitude response spectrum considering structural randomness was proposed,and the rationality of the equivalent method for designed earthquake-induced track geometric irregularities was evaluated by comparing to measured geometric track irregularities after earthquake.Analysis results show that the fitting errors of designed earthquake-induced track geometric irregularities can be controlled below 10% under different pier height conditions by the combination of sine function and linear function.When the correction coefficients under seismic fortification and rare earthquakes are set to 3.0 and 1.5,the applicability of the modified fitting model obtained by multiplying the equivalent fitting model and the correction coefficient to random structures can meet the requirements.There is not significant difference in the shape and amplitude of measured geometric track irregularities before and after earthquake,and the corresponding amplitude error of lateral vehicle body acceleration is less than 5%.When the earthquake intensity is low,train can operate normally without significant deceleration.Compared with the measured geometric track irregularities after earthquakes,designed earthquake-induced track geometric irregularities increase the amplitude of lateral vehicle body acceleration by nearly 50%,and the driving speed threshold after earthquake calculated based on designed earthquake-induced geometric track irregularities has a reasonable safety margin.The

关 键 词：桥梁工程 高速铁路 震后速度阈值 轨道不平顺 结构随机 地震损伤 行车安全 

分 类 号：U24[交通运输工程—道路与铁道工程]