循环荷载下无砟轨道-桥梁结构体系刚度退化性能  

Performance of stiffness degradation of structure system in ballastless track-bridge under cyclic load

作　　者：李龙祥 周凌宇[1] 黄戡[1,2] 张燕 赵磊[1] LI Longxiang;ZHOU Lingyu;HUANG Kan;ZHANG Yan;ZHAO Lei(School of Civil Engineering, Central South University, Changsha 410075, China;School of Civil Engineering, Changsha University of Science & Technology, Changsha 410114, China;Guangxi Communications Design Group Co. Ltd., Nanning 530029, China;Shanghai Design Institute of China Railway Group Co. Ltd., Shanghai 200070, China)

机构地区：[1]中南大学土木工程学院,湖南长沙410075 [2]长沙理工大学土木工程学院,湖南长沙410114 [3]广西交通设计集团有限公司,广西南宁530029 [4]中铁上海设计院集团有限公司,上海,200070

出　　处：《中南大学学报（自然科学版）》2019年第10期2481-2490,共10页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(51578546);高速铁路基础研究联合基金资助项目(U1434204);湖南省教育厅科学研究重点项目(18A127);长沙理工大学“双一流”科学研究国际合作拓展项目(2018IC19)~~

摘　　要：为了预测高速铁路无砟轨道梁桥结构体系的长期性能演化规律,在充分考虑轨道层间黏结性能的基础上,建立CRTSⅡ型无砟轨道-简支梁桥结构空间有限元模型。基于材料疲劳力学性能的研究,通过1次静力加载,确定材料刚度退化曲线并构造不同服役期时荷载循环加载N次后的等效静力模型,分析结构在列车荷载、温度作用或它们共同作用下的工作性能。研究结果表明:在正温度作用下,结构体系整体在纵向以受压为主;在负温度下,结构体系整体上在纵向以受拉为主;在单线列车荷载下,轨道各层纵向在梁端处受拉、跨中处受压;轨道各层应力随结构服役时间增加不断减小,各层纵向与竖向位移则不断增大;结构各层的应力与位移随结构服役时间的变化规律与材料疲劳性能的3阶段变化规律较相似;结构体系在温度与单线列车荷载共同作用下,有载侧与无载侧的力学反应稍有不同,单线列车荷载的存在仅影响结构服役初期不同侧的响应值,对结构的力学性能随服役时间变化的规律影响不大。To predict the long-term performance evolution rule of the structural system, a space finite element model of the ballastless track-bridge structure system was established on the basis of fully considering the bond performance between the orbital layers. Based on the study of the mechanical properties of material fatigue, the stiffness degradation curve of the material was determined and the equivalent static model was constructed after load cycle loading N times. The working performances of the structure under the effects of train load, temperature or their combination were analyzed, and the evolution law of the structure system during the operation process was revealed. The results show that under the action of positive temperature, the whole structure system is mainly subjected to compression, and under the action of negative temperature, it is dominated by tension. The longitudinal direction of the track under the load of single-line train is pulled at the beam end, and the track is compressed in the midspan. The stress of each layer of the orbit decreases with the increase of the service time of the structure, and the longitudinal displacement and relative displacement of each layer increase. The stress and displacement of each layer are similar to those of the three phases of material fatigue performance. Under the combined effect of temperature and single-line train, the mechanical reaction between the loading sides and the noload side is slightly different. The existence of single line train load only affects the response value of different sides of the initial service. It has little effect on the changing rule of structural mechanical properties.

关 键 词：无砟轨道-梁桥结构体系 刚度退化 等效静力分析 经时性能演化 

分 类 号：U213.2[交通运输工程—道路与铁道工程]