Influence of swelling behavior of expansive soil foundation on deformation performance of ballastless track subgrade

被引：0

作者：

Duan, Junyi ^{[1
]}

Cao, Pengyuan ^{[1
]}

Su, Yu ^{[1
]}

Lin, Yuliang ^{[2
,3
]}

Yang, Guolin ^{[2
,3
]}

机构：

[1] School of Infrastructure Engineering, Nanchang University, Nanchang,330031, China

[2] School of Civil Engineering, Central South University, Changsha,410075, China

[3] National Engineering Research Center of High-speed Railway Construction Technology, Changsha,410075, China

来源：

Zhongnan Daxue Xuebao (Ziran Kexue Ban)/Journal of Central South University (Science and Technology) | 2024年 / 55卷 / 09期

关键词：

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. © 2024 Central South University of Technology. All rights reserved;

D O I：

10.11817/j.issn.1672-7207.2024.09.025

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摘要：

引用

页码：3530 / 3542