文献类型：期刊文献

中文题名：多雨地区无砟轨道层间裂纹内水流空化发生及脱空损伤机理研究

英文题名：Study on Mechanism of Cavitation and Void Damage from Water Flow in Ballast Track Interlayer Cracks in Rainy Areas

作者：冉世欣 徐桂弘 邓文波 陈永胜 任娟娟 杨荣山

第一作者：冉世欣

机构：[1]贵州大学土木工程学院,贵州贵阳550025;[2]贵州理工学院土木工程学院,贵州贵阳550025;[3]重庆第一轨道交通运营管理有限公司,重庆400042;[4]中铁十一局集团第三工程有限公司,湖北十堰442000;[5]西南交通大学土木工程学院,四川成都610031

第一机构：贵州大学土木工程学院,贵州贵阳550025

年份：2025

卷号：47

期号：12

起止页码：140-149

中文期刊名：铁道学报

外文期刊名：Journal of the China Railway Society

收录：;北大核心:【北大核心2023】；

基金：国家自然科学基金(52268605);贵州省科技计划(黔科合基础-ZK[2022]重点027);贵州省高层次创新型人才(黔科合平台人才-GCC[2023]053)。

语种：中文

中文关键词：铁路路基;空化;数值计算;裂纹结构;损伤

外文关键词：railway subgrade;cavitation;numerical calculations;cracked structures;damage

摘要：无砟轨道复杂的带状结构体系、高周期的疲劳荷载作用、复杂的雨水环境条件等,致使充填层层间脱联、裂纹扩展等成为我国高速铁路养护维修面临的突出问题。从水动力特性分析出发,认为高速列车驶入带裂纹轨道上方瞬间,雨水在裂纹内部产生剧烈的压强变化,产生空化及空蚀损伤,从而导致多雨地区无砟轨道伤损较干燥地区快的工程现象。为验证这一想法,以现场揭板记录为基础,建立平面裂纹几何模型,利用Ansys-Fluent软件进行数值模拟计算。结果表明,高速列车通过时,在轨道板与充填层黏结薄弱位置,当裂纹形态满足本文所描述条件时,可以出现空化现象;裂纹几何模型的扩散角、会聚角、颈缩段长度、颈缩段直径、入口压力等参数,对裂纹内水域空化具有显著影响。随着裂纹扩散角度、会聚角度的增大,水域空化程度减小;随着颈缩段长度、颈缩段直径、入口压力的增大,水域空化程度增大。单空泡溃灭时对壁面中心的冲击压力80 MPa,超过C40混凝土和CA砂浆对应的抗压强度,造成材料表面塑性变形乃至空蚀损伤。在长期循环空蚀损伤中,导致多雨地区无砟轨道裂纹快速扩展。
The interplay of the complex structure of ballastless tracks,high-cycle fatigue loading,and adverse rainwater conditions has led to acute problems of interlayer dislocation and crack propagation in the filling layer posing a major challenge to the maintenance of China's high-speed railways.This paper,grounded in hydrodynamic analysis,hypothesized that the instantaneous pressure surge of rainwater within a crack,induced by a passing high-speed train,triggers cavitation and subsequent cavitation erosion.This mechanism explained the engineering phenomenon where ballastless track damage in rainy areas occurs at a faster rate than in dry areas.To validate this hypothesis,based on on-site slablifting records,a planar crack geometric model was established,and numerical simulations were carried out using Ansys-Fluent software.The results show that cavitation can occur at weakly bonded interfaces between the track slab and filling layer under the passage of high-speed trains,provided that the crack morphology meets the conditions described herein.Key parameters of the crack model,including the divergence angle,the convergence angle,the length of the necking section,the diameter of the necking section,and the inlet pressure,have a significant effect on the cavitation generation.With the increase of crack divergence and convergence angles,the degree of water cavitation decreases.Conversely,as the necking length,necking diameter,and inlet pressure increase,the degree of cavitation increases.The impact pressure from the collapse of a single cavitation bubble,can reach 8O MPa,which is sufficient to exceed the compressive strength of both C40 concrete and CA mortar,thereby inducing plastic deformation of the material surface and even cavitation erosion damage.Ultimately,long-term cyclic cavitation erosion damage accelerates the rapid propagation of cracks in ballastless tracks in rainy areas.