江淮水利科技Issue(5)：3-8,15,7.DOI:10.20011/j.cnki.JHWR.202505002
干湿循环条件下改良膨胀土力学特性及微观机理研究
Mechanical properties and microstructural characteristics of modified expansive soil under wet-dry cycles
摘要
Abstract
To elucidate the mechanism and effectiveness of fly ash-ionic stabilizer modification on expansive soil under wet-dry cycling conditions,this paper comparatively analyzed the mechanical properties and microstructural evolution patterns of natural soils,single-modified soils,and composite-modified soils before and after wet-dry cycling.Through unconfined compressive strength cross-testing,with the increase in additive content,the specimen strength first increased and then decreased,reaching its peak when the fly ash content was 15%and the volumetric ratio of the ionic stabilizer was 1:300.Wet-dry cycling tests re-vealed that composite-modified soil exhibited minimal strength decay,highest shear strength,and significantly lower cohesion reduction compared to native soil.SEM and XRD test results indicated that fly ash formed aluminosilicate cementation to fill pores,while the ionic solidified promoted clay agglomeration and reduced interlayer spacing.This synergistic effect enhanced soil compaction and water stability.This paper demonstrated that the composite improvement mechanism of"cementation-filling and lattice stabilization"through fly ash and ionic stabilizer not only improved the mechanical properties of expansive soil but also significantly suppressed strength deterioration caused by wet-dry cycles.This provides both experimental and theoretical bases for engineering improvements in regions with expansive soils.关键词
膨胀土/粉煤灰/离子固化剂/干湿循环/抗压强度Key words
expansive soil/fly ash/ionic stabilizer/wet-dry cycles/unconfined compressive strength分类
建筑与水利引用本文复制引用
龚郴彬,张家柱,代世军..干湿循环条件下改良膨胀土力学特性及微观机理研究[J].江淮水利科技,2025,(5):3-8,15,7.基金项目
安徽省(水利部淮河水利委员会)水利科学研究院青年创新计划项目(KY202305) （水利部淮河水利委员会）
