横向地震作用下高速铁路CRTSⅢ型无砟轨道-桥梁系统震致轨道不平顺研究  

Study on track irregularity of CRTSⅢballastless track-bridge system of high-speed railway under transverse earthquake

作　　者：周旺保[1,2] 彭东航 蒋丽忠 刘丽丽[1] 余建 ZHOU Wangbao;PENG Donghang;JIANG Lizhong;LIU Lili;YU Jian(School of Civil Engineering,Central South University,Changsha 410075,China;National Engineering Research Center of High-speed Railway Construction Technology,Changsha 410075,China)

机构地区：[1]中南大学土木工程学院,湖南长沙410075 [2]高速铁路建造技术国家工程研究中心,湖南长沙410075

出　　处：《铁道科学与工程学报》2023年第8期2773-2784,共12页Journal of Railway Science and Engineering

基　　金：国家自然科学基金资助项目(U1934207,52078487,52178180);湖南省交通科技项目(202011);中南大学创新驱动项目(502501006);湖南创新型省份建设专项经费资助项目(2019RS3009)。

摘　　要：为探究高速铁路轨道−桥梁系统震后轨道不平顺的产生机理,以桥面铺设CRTSⅢ型无砟轨道结构的高速铁路轨道−桥梁系统为对象,考虑钢轨、扣件、轨道板、自密实混凝土层、隔离层土工布、弹性橡胶垫、底座板等轨道结构部件,建立非线性动力仿真模型,分析轨道−桥梁系统在不同地震动强度下各关键构件的损伤规律及震致轨道残余位移分布规律,建立映射轨道不平顺计算模型,并将其与震致轨道不平顺有限元计算结果进行对比。研究结果表明:地震将引起显著的轨道不平顺,恶化钢轨的平顺程度,在设计地震和罕遇地震作用下,钢轨在梁缝处有明显折角,行车安全设计时应重点关注梁缝处的钢轨变形。钢轨的应力峰值出现在梁缝处,其应力大于钢轨的容许屈服应力。单元板式轨道结构的扣件极易在梁缝位置损坏,远离梁缝的扣件均处于健康状态。自密实混凝土与底座板不会相对滑动,二者的层间残余位移极小。在设计地震和罕遇地震下,固定支座以及滑动支座均产生显著的残余位移,而桥墩残余位移较小。隔离层以及桥墩的残余位移对于震致轨面几何形态变位的贡献可以忽略不计,震致轨道不平顺主要由扣件以及支座的残余变形引起。To explore the mechanism of track irregularities of high-speed railway track-bridge system after earthquake,the CRTSⅢballastless track-bridge system of high-speed railway was taken as the object.A nonlinear dynamic simulation model was constructed containing rail,fastener,track slab,self-compacting concrete layer,base slab,geotextile isolation layer,elastic rubber pad and other track structural components.The damage law of key components of the track-bridge system and the distribution mode of residual displacement of the track were analyzed under different intensities earthquake.The mapping calculation model of track irregularity was established and compared with the finite element calculation results of track irregularity induced by earthquake.The results show that the earthquake causes significant track irregularity and degrades the smoothness of the rail.Under design earthquake and rare earthquake,the rail has obvious bending angle at the bridge gap,and the rail deformation at the bridge gap should be paid attention to in the design of driving safety.The peak stress of the rail appears at the bridge gap,and its stress is far less than the allowable yield stress of the rail.The fasteners of the discontinuous track structure are easily damaged at the bridge gap,and the fasteners far from the bridge gap are in a healthy state.The self-compacting concrete and the base slab will not slide relatively,and the residual displacement of the isolation layer is very small.In the design earthquake and rare earthquake,the fixed and sliding bearing have significant residual displacements,while the residual displacement of pier is small.The influence of the residual displacement of the isolation layer and pier on the geometric deformation of the rail induced by the earthquake can be ignored.The track irregularity induced by the earthquake is mainly caused by the residual deformation of the fasteners and bearings.

关 键 词：高速铁路桥梁 CRTSⅢ型轨道系统 残余位移 轨道不平顺 损伤规律 映射关系 

分 类 号：U442.55[建筑科学—桥梁与隧道工程]