单元双块式无砟轨道对隧底上拱变形的适应性研究  

Adaptability Study of Unit Double Block Ballastless Track to Deformation of Tunnel Bottom Heave

作　　者：易强 刘伟斌 张宏程 施成 宁娜 YI Qiang;LIU Weibin;ZHANG Hongcheng;SHI Cheng;NING Na(Railway Engineering Research Institute,China Academy of Railway Sciences Corporation Limited,Beijing 100081,China;Maintenance Department,China Railway Kunming Group Co.Ltd.,Kunming 650011,China)

机构地区：[1]中国铁道科学研究院集团有限公司铁道建筑研究所,北京100081 [2]中国铁路昆明局集团有限公司工务部,昆明650011

出　　处：《铁道建筑》2022年第9期9-13,共5页Railway Engineering

基　　金：国家重点研发计划(2018YFE0207100);中国国家铁路集团有限公司科技研究开发计划(J2020G001)。

摘　　要：针对隧底结构上拱变形容易导致双块式无砟轨道产生离缝或裂纹的问题,提出单元式道床板结构。采用双线性内聚力模型,计算分析隧底上拱条件下单元式道床板与隧底仰拱回填层之间黏结作用和预埋钢筋对轨道结构受力、变形以及层间状态的影响规律,并与纵连式道床板进行对比。结果表明:对于单元式道床板,层间黏结作用可有效抑制离缝的产生,黏结附加力使得道床板拉应力略有增大;层间初始黏结作用良好条件下预埋钢筋对轨道结构受力及变形影响不显著,上拱幅值过大使得层间黏结失效后预埋钢筋可改善层间状态。与纵连式道床结构相比,单元式道床板应力水平明显降低,离缝范围较小,层间离缝主要位于上拱中心板端位置。In view of the problem that the heave deformation of the tunnel bottom structure easily leads to the separation joints or crack of the double block ballastless track,a unit ballast bed plate structure was proposed.The bilinear cohesion model was used to calculate and analyze the binding effect between the unit ballast bed plate and the backfill layer of the inverted arch at the tunnel bottom under the condition of the tunnel bottom heave,and the influence of the embedded reinforcement on the stress,deformation and interlayer state of the track structure,and the comparison with the longitudinal ballast bed plate was made.The results show that for the unit ballast bed plate,the interlayer bonding can effectively suppress the occurrence of separation joints,and the additional bonding force slightly increases the tensile stress of the ballast bed plate.Under the condition that the initial bonding between layers is good,the influence of embedded reinforcement on the stress and deformation of track structure is not significant.If the heave amplitude is too large,the embedded reinforcement can improve the state between layers after the failure of interlayer bonding.Compared with the longitudinal ballast bed structure,the stress level of the unit track ballast plate is significantly reduced,the range of separation joints is small,and the interlayer separation joints are mainly located at the end of the heave center plate.

关 键 词：双块式无砟轨道 隧底上拱 单元式道床 层间状态 结构应力 

分 类 号：U213.2[交通运输工程—道路与铁道工程]