摘要
采用增加道床厚度的方式维持线路的平顺性会导致道床厚度突破设计标准,边坡侵入限界,存在安全隐患。针对这一问题,基于离散单元法,采用多面体单元模拟真实道砟颗粒外形,通过建立不同厚度的道床离散元模型,对超厚道床的稳定性与结构强化措施进行研究。结果表明:厚度增加会加剧道床的累积变形,180 cm超厚道床轨枕沉降为35 cm普通道床的4.7倍;道砟颗粒呈现出向边坡流动的趋势,颗粒位移及接触力均随着道床变厚而增加;道床厚度从35 cm增至180 cm,边坡颗粒的最大位移与平均接触力分别扩大了2.7、5.7倍;两侧边坡的扩大使得道床超出建筑限界,可设置挡砟墙增强道床的稳定性;对于180 cm超厚道床,两侧设置挡砟墙后边坡宽度降低了84.1%;设置挡砟墙可增强道床的横向阻力,对降低道床累积变形作用显著,轨枕沉降最高降低了82.5%,颗粒最大位移降低了59.6%,道床横向阻力最高提升了25.7%,道床稳定性显著提高。
Maintaining the smoothness of the line by increasing the thickness of the ballast bed can lead to the thickness of the ballast bed exceeding the design standards,slope intrusion into the limit,and pose safety hazards.To address this issue,based on the discrete element method,polyhedral elements were used to simulate the shape of real ballast particles.By establishing discrete element models of ballast beds with different thicknesses,the stability and structural strengthening measures of ultra-thick ballast beds were studied.The results show that an increase in thickness will exacerbate the cumulative deformation of the ballast bed,and the settlement of the sleepers on the 180 cm thickness ballast bed is 4.7 times that of the 35 cm ballast bed.The ballast particles show a trend of flowing towards the slope,and the particle displacement and contact force increase with the thickening of the ballast bed.The thickness of the ballast bed is increased from 35 cm to 180 cm,and the maximum displacement and average contact force of the slope particles is increased by 2.7 and 5.7 times,respectively.The expansion of the slopes on both sides causes the ballast bed to exceed the building limit,and ballast walls can be installed to enhance the stability of the ballast bed.For an ultra-thick ballast bed with a thickness of 180 cm,the width of the slope has been reduced by 84.1% after setting ballast walls on both sides.Setting up a ballast wall can enhance the lateral resistance of the track bed,significantly reducing the cumulative deformation of the ballast bed.The maximum settlement of the sleepers is reduced by 82.5%,the maximum displacement of particles is reduced by 59.6%,and the lateral resistance of the ballast bed is increased by 25.7%.The stability of the track bed is significantly improved.
作者
李毅
徐旸
韩宏洋
郄录朝
余文颖
LI Yi;XU Yang;HAN Hongyang;QIE Luchao;YU Wenying(Railway Engineering Research Institute,CARS,Beijing 100081,China;State Key Laboratory for Track System of High-speed Railway,CARS,Beijing 100081,China)
出处
《铁道建筑》
北大核心
2023年第11期25-30,共6页
Railway Engineering
基金
中国国家铁路集团有限公司科技研究开发计划(P2022G013)
中国铁道科学研究院集团有限公司基金(2022YJ054)
中国科协青年人才托举工程(YESS20210173)。
关键词
超厚道床
稳定性
数值模拟
有砟轨道
结构强化
道床累积变形
颗粒位移
接触力
ultra-thick ballast bed
stability
numerical simulation
ballasted track
structural strengthening
cumulative deformation of ballast bed
particle displacement
contact force
作者简介
第一作者:李毅(1996-),男,助理研究员,硕士。E-mail:cienliyi@qq.com;通信作者:徐旸(1989-),男,副研究员,博士。E-mail:xuyangcars@qq.com。
