摘要
针对持续高温作用下纵连板式无砟轨道结构因温度应力过大而产生严重病害的问题,提出部分解锁方案以释放其温度应力。为量化解锁后轨道结构温度应力的释放效果并探究其释放原理,建立部分解锁后CRTSⅡ板式无砟轨道数值计算模型,分析整体温升作用下层间界面损伤的演化规律和部分解锁后轨道结构对温度应力的释放效果。研究表明:整体温升作用下,由于解锁后轨道板和底座板纵向位移差较大,导致轨道结构层间损伤、离缝产生的临界整体温升较低;解锁后轨道结构层间离缝产生的临界整体温升为13℃。由于纵连板式无砟轨道结构体系的转变,且层间黏结强度随整体温升的升高而降低,解锁后轨道板和宽窄接缝的温度应力得到了部分释放;当整体温升为50℃时,轨道板纵向应力最大释放量可达17.5 MPa,相比于解锁前下降了95.5%;宽窄接缝纵向应力释放量最大可达17.35 MPa,相比于解锁前下降了95.3%。随整体温升的不断升高,层间界面损伤不断扩展,轨道板纵向约束减弱,故纵向应力反而降低;解锁后宽窄接缝温度应力随整体温升的变化规律受层间离缝面积影响,其随着整体温升升高呈先增大后减小再增加趋势。
Aiming at the problem of serious diseases caused by excessive temperature stress in longitudinal slab ballastless track structure under continuous high temperature,a partial unlocking scheme is proposed to release its temperature stress.In order to quantify the release amount of thermal stress of track structure after unlocking and explore its principle of thermal stress release,a numerical model of partially unlocked CRTSⅡslab ballastless track is established to analyze the evolution law of the interface damage and the release effect of the partially unlocked CRTSⅡslab ballastless track on temperature stress in this paper.Results show that:Due to the large longitudinal displacement difference between the track slab and the support layer of the partially unlocked CRTSⅡslab ballastless track under load of overall temperature rise,the critical overall temperature rise of the interface damage and delamination is low;the critical overall temperature rise of the interface delamination is 13℃.Due to the change of the longitudinal connection system of the track structure and the decrease of the interlayer bonding strength with the rise of the overall temperature,the temperature stress of the track plate and the wide and narrow joints is released.When the overall temperature rise is 50℃,the maximum longitudinal stress release of the track slab is 17.5 MPa,with a decrease of 95.5%,and the maximum longitudinal stress release of the wide and narrow joints is 17.35 MPa,with a decrease of 95.3%.The longitudinal restraint strength of track plate decreases due to the continuous expansion of interlayer interface damage,which makes the longitudinal stress of track plate decrease with the increase of overall temperature rise.After the longitudinal slab ballastless track is unlocked,the variation of temperature stress of wide and narrow joints with the overall temperature rise is affected by the expansion of interlayer separation area,which increase first,then decrease,and then increase again.
作者
蒋典佑
林锦镇
曹毅杰
刘钰
孙晓丹
杨怀志
朱星盛
JIANG Dianyou;LIN Jinzhen;CAO Yijie;LIU Yu;SUN Xiaodan;YANG Huaizhi;ZHU Xingsheng(School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;Beijing-Shanghai High Speed Railway Co.,Ltd.,Beijing 100038,China)
出处
《铁道标准设计》
北大核心
2024年第1期65-71,共7页
Railway Standard Design
基金
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)。
关键词
高速铁路
板式无砟轨道
部分解锁
温度力释放
层间界面
high-speed railway
slab track
partially unlocked
temperature force release
interface
