中南大学学报（自然科学版）2024，Vol.55Issue(9)：3530-3542,13.DOI:10.11817/j.issn.1672-7207.2024.09.025
膨胀土地基膨胀特性对无砟轨道路基变形性能的影响
Influence of swelling behavior of expansive soil foundation on deformation performance of ballastless track subgrade
摘要
Abstract
To study the impact of the swelling behavior in expansive soil foundations on the mechanical and deformation characteristics of ballastless track subgrades,firstly,the thermal properties of materials were introduced to simulate the swelling behavior of expansive soils through thermal-force coupling analysis,based on the theory of equivalence between temperature and moisture fields.Secondly,a three-dimensional numerical model of ballastless track-subgrade-expansive soil foundation for double-line railways was established and verified.Finally,the effects of the swelling potential(denoted by the coefficient of thermal expansion)and the swelling area(denoted by the longitudinal length of the swelling area)of the expansive soil foundation on the mechanical and deformation behavior of the ballastless track subgrade were investigated.The results show that localized water immersion causes swelling in the expansive soil foundation,resulting in heave,longitudinal irregularity and lateral tilting of the ballastless track structure.These effects are more pronounced with the increase of swelling potential and area in the foundation.However,when the length of the swelling area along the longitudinal direction of the subgrade exceeds 10 m,there is only a small increase in the lateral inclination angle for the ballastless track structure.Furthermore,the compression of the subgrade fillers results in an attenuation of the heave,and the attenuation rate of the heave increases with the increase of the swelling potential and decreases with the increase of the swelling area in the foundation.The heave amount,longitudinal unevenness of heave and lateral inclination angle of the ballastless track structure are suggested as the performance control indexes for ballastless track subgrades in expansive soils.Additionally,measures should be implemented to mitigate the uneven transverse distribution of subgrade heave and moisture gradient in expansive soil foundations,aiming to alleviate the lateral inclination of the ballastless track structures.关键词
膨胀土地基/隆起变形/膨胀潜势/无砟轨道/侧向倾斜Key words
expansive soil foundation/heave deformation/swelling potential/ballastless track/lateral tilting分类
交通工程引用本文复制引用
段君义,曹鹏远,粟雨,林宇亮,杨果林..膨胀土地基膨胀特性对无砟轨道路基变形性能的影响[J].中南大学学报（自然科学版）,2024,55(9):3530-3542,13.基金项目
国家自然科学基金资助项目(52208348,52208347) （52208348,52208347）
江西省自然科学基金资助项目(20232ACG01003,20232BAB204083,20224BAB214064,20224BAB214063) （20232ACG01003,20232BAB204083,20224BAB214064,20224BAB214063）
中国博士后基金资助项目(2023M731436)(Projects(52208348,52208347)supported by the National Natural Science Foundation of China （2023M731436）
Projects(20232ACG01003,20232BAB204083,20224BAB214064,20224BAB214063)supported by the Natural Science Foundation of Jiangxi Province （20232ACG01003,20232BAB204083,20224BAB214064,20224BAB214063）
Project(2023M731436)supported by the Postdoctoral Science Foundation of China) （2023M731436）
