中国水土保持科学2025，Vol.23Issue(6)：65-77,13.DOI:10.16843/j.sswc.2025106
不同掺量PAM和PVA对砂土与粉土物理性质及抗剪强度的影响
Effects of different dosages of PAM and PVA on the physical properties and shear strengths of sandy soil and silty soil
摘要
Abstract
[Background]When conducting ecological restoration of sandy and silty soil slopes in Dongcaoying village,Baodaoling town,Yanqing district,Beijing,issues such as substrate detachment,slope sliding and soil erosion occurred,resulting in poor stability of the restoration.Currently,the influence of different adhesive agent types and dosages on the properties of the substrate is not clear,and further research is needed to optimize the ecological restoration plan and enhance the stability of the slope.[Methods]This study took sandy soil and silt soil as the research objects and conducted indoor experiments to explore the effects of polyacrylamide(PAM)and polyvinyl alcohol(PVA)at dosages of 0(control group,CK),0.2%,0.4%,0.6%,and 0.8%(w/w)on soil density,porosity,the mass fraction of water-stable aggregates,and shear strength.The soil solidification mechanism was also revealed through electron microscopy analysis.[Results]1)The adhesives significantly reduced soil bulk density(P<0.05).The reduction in PVA(6.8%-10.3%)was higher than that of PAM(3.4%-4.8%)in sandy soil,and the reduction in PVA(11.7%-13.1%)was also higher than that of PAM(10.3%-11.7%)in silty soil.The effect of PVA was better.2)The adhesives significantly increased soil porosity(P<0.05),and the improvement effect of PVA was more significant than that of PAM,but there was no significant difference among the dosages(P>0.05).3)The adhesives significantly increased the mass fraction of large aggregates(P<0.05),enhanced the stability of soil aggregates,and the effect of PAM dosage was more obvious.4)The peak value of the principal stress difference of the soil modified by the adhesive increases in accordance with the Mohr-Coulomb law as the confining pressure increases.The strength improvement of sandy soil is better than that of silt soil,and the optimal effect is achieved at a range of 0.4%to 0.6%.Moreover,the cohesion of both types of soil increases after modification,but the internal friction angle shows different responses:the cohesion of sandy soil decreases with the increase of the admixture content,while there is no significant improvement in silt soil(P>0.05).5)The adhesives enhanced the stability of the soil body by aggregating small aggregates,forming thread connections and surface sheet-like structures.[Conclusions]PAM and PVA have significant effects on improving the physical and mechanical properties of soil.The optimal dosage is clearly 0.4%-0.6%.The results can provide theoretical support for the differences in the application effects of adhesives in different soil types,and are of great guiding value for reducing soil erosion and promoting ecological restoration projects.关键词
客土喷播/黏合剂/团聚体结构/扫描电镜/抗剪性能Key words
soil spraying/adhesive/aggregate structure/scanning electron microscope/shear resistance performance分类
农业科技引用本文复制引用
WEI Xue,ZHANG Chuanyao,ZHU Changhong,YUAN Feng,SONG Guilong..不同掺量PAM和PVA对砂土与粉土物理性质及抗剪强度的影响[J].中国水土保持科学,2025,23(6):65-77,13.基金项目
国家草业技术创新中心(筹)重大创新平台建设专项项目"防沙治沙新材料、新技术研发与示范"(CCPTZX2024GJ04) （筹）
