整体温升作用下纵连板式无砟轨道宽窄接缝损伤演化研究  

Study on damage evolution of wide and narrow joints in longitudinally connected slab ballastless track under load of overall temperature rise

作　　者：刘钰 赵国堂[1,2,3] 曹毅杰[1,2] 许乾奇 孙晓丹 LIU Yu;ZHAO Guotang;CAO Yijie;XU Qianqi;SUN Xiaodan(School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;Key Laboratory of High-speed Railway Engineering of Ministry of Education,Southwest Jiaotong University,Chengdu 610031,China;China State Railway Group Co.,Ltd.,Beijing 100844,China)

机构地区：[1]西南交通大学土木工程学院,成都610031 [2]西南交通大学高速铁路线路工程教育部重点实验室,成都610031 [3]中国国家铁路集团有限公司,北京100055

出　　处：《北京交通大学学报》2021年第4期19-27,共9页JOURNAL OF BEIJING JIAOTONG UNIVERSITY

基　　金：国家自然科学基金(51708459,51878578);中国国家铁路集团有限公司科技研究开发计划重大课题(K2020G007)。

摘　　要：为探明整体温升荷载对纵连板式无砟轨道宽窄接缝的损伤演化规律,建立了纵连板式无砟轨道宽窄接缝损伤数值模型,模拟了轨道板宽窄接缝混凝土劣化、施工温差及初始裂纹条件下的宽窄接缝损伤情况,探讨了各种因素对宽窄接缝损伤的影响.研究结果表明:整体温升作用下,宽窄接缝的损伤主要集中在接缝处的板边缘位置,接缝损伤随温度升高逐渐增大.宽接缝压溃会加剧轨道板偏心受压,导致层间界面离缝;接缝混凝土强度越大,接缝损伤临界温升和压溃临界温升越高;施工温差越大,整体温升条件下宽窄接缝损伤情况越严重.保证宽窄接缝施工温度相同,可有效避免整体温升作用下宽窄接缝损伤程度的差异;轨道板初始裂纹会显著增加宽窄接缝的损伤程度,同时将导致宽接缝压溃临界温升值明显降低.To explore the damage evolution law of wide and narrow joints in longitudinally connected slab ballastless track under the load of overall temperature rise,a numerical model of longitudinally connected slab ballastless track for the damage is established.The damage of wide and narrow joints under various concrete deterioration,construction temperature difference,and initial cracking conditions are simulated.Based on the simulation,the effects of all the above factors on the damage of the joints are discussed.The results show that:Under load of overall temperature rise,the damage of the joints is concentrated at the edge of the slab joints.The joint damage increases with the increase of temperature.Wide joint crushing will aggravate the eccentric compression of the track slab,leading to the generation of the interfacial delamination within the track structure.The greater the concrete strength of the joint,the higher the critical temperature rise for the joint damage and for the concrete crushing.The larger the construction temperature difference,the severer the damage of the joints under load of overall temperature rise.To effectively reduce the difference in the damage of the wide and narrow joints under overall temperature rise,it is better to ensure the same construction temperature for the wide and narrow joints.The initial crack of the track slab will significantly increase the joint damage degree,and meanwhile reduce the critical temperature rise for the concrete crushing of wide joints.

关 键 词：轨道工程 板式无砟轨道 扩展有限元 损伤演化 内聚力模型 离缝 

分 类 号：U213.244[交通运输工程—道路与铁道工程]