西北地质2026，Vol.59Issue(2)：59-71,13.DOI:10.12401/j.nwg.2025136
矿物-孔隙耦合作用控制下富县黄土增湿变形差异性
Differences in Loess Wetting-Induced Deformation in Fuxian County Controlled by Mineral-Pore Coupling Effects
摘要
Abstract
The study of the wetting-induced deformation mechanism of loess is of great importance for engi-neering disaster prevention and control in the Loess Plateau region.This research focuses on the Q3p and Q2p loess from Fuxian County,northern Shaanxi,aiming to reveal the deformation behavior and underlying mecha-nisms of loess from different geological eras under wetting conditions.A comparative study of the engineering properties of the two types of loess was systematically conducted through a series of physico-mechanical tests,mineral composition analysis,scanning electron microscopy(SEM)observations,and multi-condition consolida-tion-collapse tests.The results indicate that the consolidation deformation process of both types of loess can be divided into three stages:slow deformation under low pressure,accelerated deformation under medium pressure,and stabilized deformation under high pressure.Under high pressure conditions,the consolidation deformation becomes more sensitive to changes in initial water content.With increasing initial water content,the compres-sion deformation of the Q3p specimens intensifies significantly,while that of the Q2p specimens weakens.In col-lapse tests,the two groups exhibited fundamentally opposite deformation characteristics:the Q3p specimens showed typical collapse behavior,with the collapse coefficient initially increasing and then decreasing with ris-ing pressure,whereas the Q2p specimens displayed certain expansion characteristics.As the initial water content increased,the collapse coefficient of the Q3p specimens gradually decreased,while the expansion tendency of the Q2p specimens also weakened.Microstructural analysis revealed that the stability of the loess microstructure,particularly the presence of large pores,provides the necessary space for compression and collapse deformation.Mineral composition analysis indicated that the dissolution of soluble salt minerals(e.g.,calcite)exacerbates soil compression and collapse deformation,while the water-absorbing expansion of clay minerals(e.g.,illite)partial-ly suppresses these behaviors.This study elucidates the controlling mechanism of the coupling effect between mineral composition and microstructure on the wetting-induced deformation behavior of loess,providing impor-tant theoretical support and practical guidance for engineering construction and geohazard mitigation in loess re-gions.关键词
黄土/增湿变形/扫描电镜/微观机理Key words
Loess/wetting-induced deformation/Scanning Electron Microscopy/microscopic mechanisms分类
天文与地球科学引用本文复制引用
纪成亮,谢婉丽,刘琦琦,周嘉豪,马陈,曲晨飞,李仁杰,王立波..矿物-孔隙耦合作用控制下富县黄土增湿变形差异性[J].西北地质,2026,59(2):59-71,13.基金项目
国家自然科学基金项目(42372320、41972292),陕西省创新能力支撑计划项目(2021TD-54),陕西省重点研发计划项目(2022ZDLSF06-03)联合资助. （42372320、41972292）
