摘要
在弱纵连施工过程中,为了避免轨道板凿除宽窄接缝后在解锁位置发生较大的位移变形,有必要明确不同解锁条件、不同解锁温度下轨道结构的受力变形特征,指导现场施工。基于梁轨相互作用原理和有限元法,建立无砟轨道-多跨简支梁桥精细化模型,利用有限元软件中“生死单元”的功能分步骤解锁轨道板,研究桥上CRTS Ⅱ型板式无砟轨道在不同解锁工况下轨道结构受力变形规律,据此分析得出合理解锁条件及解锁温度,并对应仿真计算中板端植筋工况,在预加固植筋地段进行了现场解锁实验。研究结果表明:不松开钢轨扣件,解锁板温在初始施工锁定板温±5℃范围内,可以直接解锁宽窄接缝;解锁板温在初始锁定板温±5℃之外,轨道板纵向位移不满足规范限值要求,需严格控制解锁温度;松开扣件解锁轨道板,轨道结构整体受力变形增大,轨道板纵向位移超过规范允许限值,建议解锁时不松开钢轨扣件;板端植筋有利于减小解锁后结构的受力变形,但轨道板纵向应力除外,板端植筋可作为解锁时的预防性手段。现场试验表明,解锁时轨道板板端植筋,宽窄接缝位置处轨道板间相对位移几乎不发生变化。研究成果对于CRTS Ⅱ型板式无砟轨道高温胀板病害提出了一种新的解决思路—弱纵连CRTS Ⅱ型板式无砟轨道。
In order to avoid the large displacement deformation at the unlocking position,during the construction of weak longitudinal connection,it is necessary to clarify the stress and deformation characteristics of the track structure under different unlocking conditions and different unlocking temperatures,and guide the on-site construction.Based on beam rail interaction principle and the finite element method,the ballastless track-simply supported beam bridge model was established.Using the function of model change in the finite element software to unlock the track plate step by step,the stress and deformation was analyzed when the CRTS II slab track was unlocked.The reasonable unlocking conditions and unlocking temperature were obtained,and the on-site unlocking experiment was carried out in the pre-reinforced area corresponding to the planting reinforcement condition in the simulation calculation.The research results are shown as follows.Without loosening the rail fasteners,the unlocking plate temperature is within the range of the initial construction locking plate temperature±5℃,and the wide and narrow joints can be directly unlocked.The unlocking plate temperature is outside the initial locking plate temperature±5℃.The longitudinal displacement of the track plate does not meet the requirements of the specification limit.The unlocking temperature needs to be strictly controlled.Release the fastener to unlock the track plate,the longitudinal displacement of the track plate exceeds the allowable limit of the specification,it is recommended not to loosen the rail fastener when unlocking.Post-installed reinforcement bars at the end of plate is beneficial to reduce the stress and deformation of the structure except for the longitudinal stress of the track slab.Post-installed reinforcement bars can be used as a preventive measure during unlocking.On-site unlocking experiment shows that the relative displacement between the track slabs at the position of the wide and narrow joints hardly changes when post-installed reinforcement bars at the end of plate.A new solution for CRTS II slab track slab-expanding disease is proposed:weaken longitudinal connection of the CRTS II slab track.
作者
蔡嘉升
陈进杰
王建西
陈龙
李杨
王瑞
CAI Jiasheng;CHEN Jinjie;WANG Jianxi;CHEN Long;LI Yang;WANG Rui(Key Laboratory of Roads and Railway Engineering Safety Control of Ministry of Education,Shijiazhuang Tiedao University,Shijiazhuang 050043,China;State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures,Shijiazhuang Tiedao University,Shijiazhuang 050043,China;Hebei Key Laboratory of Geotechnical Engineering Safety and Deformation Control,Hebei University of Water Resources and Electric Engineering,Cangzhou 061001,China)
出处
《铁道科学与工程学报》
EI
CAS
CSCD
北大核心
2023年第5期1533-1542,共10页
Journal of Railway Science and Engineering
基金
国家重点研发计划(2021YFB2601000)
河北省自然科学基金资助项目(E2020210092)
京津冀基础研究合作专项(河北省自然科学基金)(E2021210142)
中国国家铁路集团有限公司科技研究开发计划课题(P2019G055)
河北省高校百名优秀创新人才支持计划(III)项目(SLRC2019036)。
关键词
弱纵连
锁定板温
解锁温度
CRTSⅡ型板式无砟轨道
梁轨相互作用
weak longitudinal connection
locking plate temperature
unlocking condition
CRTS II slab track
track-bridge interaction
