中国铁道科学2025，Vol.46Issue(6)：1-11,11.DOI:10.3969/j.issn.1001-4632.2025.06.01
高速铁路中低压缩性地基土固-液-气三相演化机制研究
Study on the Solid-Liquid-Gas Phase Evolution Mechanism of Medium-Low Compressible Foundation Soils for High-Speed Railways
摘要
Abstract
Medium-low compressible clays are used as natural foundations for high-speed railways(HSR),demonstrating favorable settlement control.However,their deformation characteristics during compression are difficult to explain by conventional drainage-consolidation theory,limiting their engineering application.This study focuses on such soils in the Hefei area,conducting high-precision compression drainage tests,measurements of strongly and weakly bound water content,soil-water characteristic curve(SWCC)tests,and microstructural pore analyses.The research systematically reveals their liquid-solid-gas phase evolution mechanism.The results indicate that:Medium-low compressible clay exhibits rapid deformation and fast convergence during initial loading,with approximately 80%of the total deformation occurring within 0.5 hour after loading and minimal pore-water drainage,showing distinct atypical drainage deformation behavior;Bound water accounts for 74.4%of the natural water content(strongly bound:32.7%;weakly bound:41.7%).Although free water constitutes 25.6%of the natural water content(6.0%of total water),its effective drainage is impeded due to dominant capillary suction forces,insufficient hydraulic gradient,and the constraints of the pore structure.Particle fragmentation and refinement increase the content of particles smaller than 2 μm from 8.1%to 15.3%.Compression leads to the conversion of larger pores into smaller ones,increasing the proportion of pores smaller than 0.2 μm to 25.4%.Results signify a microstructural restructuring characterized by particle refinement,pore compression,and structural densification.The compression deformation process of medium-low compressible clays under external loading results from the co-evolution of solid-phase reorganization,liquid-phase adsorption/retention,and pore compression,providing a micro-scale basis and theoretical support for deformation control of such soil foundations in high-speed railways.关键词
高速铁路/中低压缩性黏土/压缩变形/结合水/微观结构演化Key words
High-speed railways/Medium-low compressible clay/Compression deformation/Bound water/Microstructural evolution分类
交通工程引用本文复制引用
余雷,蒋红光,王祥,周先才,刘依依,姚成志,黄世光,杨为民,孙健凯..高速铁路中低压缩性地基土固-液-气三相演化机制研究[J].中国铁道科学,2025,46(6):1-11,11.基金项目
国家自然科学基金资助项目(52378353) （52378353）
中国国家铁路集团有限公司科技研究开发计划课题(N2023G062) （N2023G062）
中铁工程设计咨询集团有限公司重点课题(KY2024A010) （KY2024A010）
