钢管混凝土双块式轨枕道床复合受力性能试验  

Experimental test on composite working performance of track bed with concrete-filled steel tube connected double-block sleepers

作　　者：刘晓春[1,2] 姚军[1,2] 罗延亮 李启航 朱志辉 余志武[1,2] LIU Xiaochun;YAO Jun;LUO Yanliang;LI Qihang;ZHU Zhihui;YU Zhiwu(National Engineering Research Center of High-speed Railway Construction Technology,Central South University,Changsha 410075,China;School of Civil Engineering,Central South University,Changsha 410075,China;China Railway Siyuan Survey and Design Group Co.,Ltd.,Wuhan 430063,China)

机构地区：[1]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 [2]中南大学土木工程学院,湖南长沙410075 [3]中铁第四勘察设计院集团有限公司,湖北武汉430063

出　　处：《铁道科学与工程学报》2024年第10期4040-4052,共13页Journal of Railway Science and Engineering

基　　金：国家重点研发项目(2022YFB2603301);国铁集团实验室基础研究项目(L2021G006);国家自然科学基金资助项目(U1934217,52078498);湖南省自然科学基金资助项目(2019JJ40383);湖南省教育厅科学研究项目(18K003)。

摘　　要：新型钢管混凝土(CFT)双块式轨枕采用钢管混凝土取代了桁架钢筋的连接构件作用,具有结构简单、安全耐久性好等优点。为研究钢管混凝土双块式轨枕与现浇混凝土道床所形成的轨道结构的复合受力性能,采用某实际工程的材料和工艺制作了一段足尺CFT轨枕减振道床和现浇整体道床,经疲劳试验验证后,用绳锯将其沿横向切割成单承轨台和双承轨台的CFT轨枕道床试件,分别开展试件的轨下截面加载试验和中间截面加载试验,分析道床试件中轨枕、现浇道床、底座板混凝土和钢筋的应力、变形及裂缝的开展演化规律。试验结果表明:CFT轨枕道床受力破坏过程均表现出整体工作、带裂缝工作和破坏的典型三阶段特征;中间截面加载试件破坏时受拉钢筋被拉断而受压区混凝土未被压碎,类似于低筋破坏,轨下截面加载试件因竖向裂缝和弯剪区段斜裂缝之间的混凝土被压碎剥落而失效,受拉纵筋未屈服,类似于斜压破坏;CFT轨枕整体道床试件抗裂能力、承载能力更高,整体道床试件开裂荷载约为减振道床试件相应值的4.7倍,其极限荷载约为减振道床的2.3倍,道床与底座板之间采用拉结钢筋连接后能大幅提升轨道结构刚度和承载能力。CFT轨枕与现浇道床界面黏结及整体工作性能良好,研究成果可供钢管混凝土双块式无砟轨道理论研究和工程应用参考。The new concrete-filled steel tube(CFT)connected double-block sleeper uses concrete-filled steel tubes to replace the connecting components of the truss steel bars.It has the advantages of simple structures and excellent safety and durability.To investigate the composite working performance of the track structure formed by a concrete-filled steel tube sleeper and cast-in-place track bed,a full-size CFT sleeper vibration-damping track bed and a monolithic track bed were made.After verification by fatigue test,it was cut transversely into CFT sleeper track bed specimens.The specimens were subjected to loading tests conducted on under-rail section and middle section to analyze the stress and deformation of sleepers,track beds,base plates and steel bars.The results demonstrate that the failure process of the CFT sleeper track bed shows the typical three-stage characteristics during the elastic stage,the cracking stage,and the damage stage.When the specimens subjected to middle section loading failed,the tensile steel bars were pulled off but the concrete in the compression zone was not crushed,which is similar to the failure due to the lack of reinforcement.When the specimens subjected to under�rail section loading failed,the steel bars did not yield,but the concrete between vertical cracks and oblique cracks in the bending and shear sections was crushed and peeled off,which is similar to the failure due to diagonal compression.Compared with the specimens from the CFT sleeper vibration-damping track bed,the cracking load of the integral track bed specimen is approximately 4.7 times,and the ultimate load is approximately 2.3 times.The stiffness and load-bearing capacity of the track structure can be greatly improved by using tie steel bars to connect the track bed and the base plate.The interface bonding performance and composite working performance of CFT sleepers and cast-in-place track beds are satisfactory.The study can provide a reference for theoretical research and engineering applications of concrete-filled

关 键 词：钢管混凝土 双块式轨枕 无砟轨道 复合受力 静载试验 

分 类 号：U213.211[交通运输工程—道路与铁道工程]