冰块冲击作用下CRTS Ⅲ型无砟轨道板损伤及变形数值模拟分析
Numerical Analysis of Damage and Deformation of CRTS Ⅲ Ballastless Track Slab Subject to the Impact of Ice Block
宋小林 1傅炫然 1余黄胜 1肖定军2
作者信息
- 1. 西南交通大学轨道交通运载系统全国重点实验室,四川成都 610031
- 2. 西南科技大学环境与资源学院,四川绵阳 621010
- 折叠
摘要
为研究附着在高速列车底部的冰块脱落后对高速铁路轨道板等基础结构造成的冲击损伤影响,采用光滑粒子-有限元耦合(SPH-FEM)方法,利用数值模拟软件LS-DYNA建立冰块冲击CRTS Ⅲ型板式无砟轨道的动力有限元分析模型,分析冰块冲击荷载作用下无砟轨道变形和损伤特征及其演化过程,探讨冰块半径、冲击速度和冲击角度对轨道板变形和损伤的影响.结果表明:圆柱形冰块垂直冲击轨道板时,会在其表面形成碗状凹坑,最大凹陷深度位于冲击中心附近,凹坑直径与冰块直径相当,凹坑边缘分布环形裂纹;模型最大凹陷深度和失效单元个数均随冰块半径和冲击速度的增大而增大,但会随冲击角度的增大而减小,冲击角度从0°增加至15°时降低最为显著,最大凹陷深度和失效单元个数分别减小89％和80％;当冰块半径从30 mm增加至60 mm时,最大凹陷深度从0.079 mm增至0.139 mm,失效单元个数从36个增至973个;当冲击速度由40 m·s-1增至100 m·s-1时,最大凹陷深度和失效单元个数由0.014 mm和0个分别增至0.079 mm和36个.研究成果可为冰雪天气高速列车限行及轨道板寿命评估提供参考.
Abstract
To investigate the impact damage of track slabs caused by detached ice blocks adhering to the underbody of high-speed trains,a dynamic finite element analysis model for the ice impact on CRTS Ⅲballastless track slab was established coupled with smoothed particle hydrodynamics(SPH)and finite element method(FEM)by utilizing the LS-DYNA software.The characteristics of the slabs deformation and damages imparted by ice blocks were analyzed and the influence of ice block radius,impact velocity,and impact angle on the patterns was also investigated.The numerical results reveal that when a cylindrical ice block impacts the track slab vertically,a bowl-shaped depression is formed on its surface,with the maximum depression depth located near the center of the impact.The diameter of the depression is similar to that of the ice block,and annular cracks are distributed around the edge of the depression.The maximum depression depth and the number of failed elements increase with the rise of the ice block radius and impact velocity,while decreasing with the increase of the impact angle.The impact angle from 0° to 15° has the most significant reduction,with a maximum depression depth and failed element number decreasing by 89％and 80％,respectively.When the ice block radius extend from 30 mm to 60 mm,the maximum depression deepens from 0.079 mm to 0.139 mm,and the number of failed elements increases from 36 to 973.Moreover,with the increase of the impact velocity from 40 m·s-1 to 100 m·s-1,the maximum depression depth and the number of failed elements increase from 0.014 mm and 0 to 0.079 mm and 36,respectively.The results can provide references for the service life assessment of track slab and speed limit of high-speed trains in ice and snow weather.
关键词
高速铁路/轨道板/损伤/变形/冲击作用/冰块/数值模拟Key words
High-speed railway/Track slab/Damage/Deformation/Impact/Ice block/Numerical simulation引用本文复制引用
基金项目
国家自然科学基金(52078433)
四川省科技计划(2020YFH0007)
出版年
2024
国家科技期刊平台
NSTL
万方数据