水土保持研究2024，Vol.31Issue(6)：161-167,7.DOI:10.13869/j.cnki.rswc.2024.06.019
添加硫酸钙对崩壁碎屑层土壤抗剪强度的影响
Analysis of the Enhancing Effect of Calcium Sulfate on the Shear Strength of Clastic Layer Soil
摘要
Abstract
[Objective]The aims of this study are to explore the mechanical strength and microscopic characteristics of soil in the debris layer of collapsed walls in Fujian Province under different conditions of calcium sulfate application,and to provide data support for future soil restoration and soil and water conservation management.[Methods]This study focuses on the debris layer soil of typical granite collapsed rock gullies in Fujian Province.Calcium sulfate was employed as the ameliorating agent,with four concentration gradients(0,5,10,15 g/kg).Through indoor remolding soil tests and direct shear tests,cohesive force and internal friction angle of the ameliorated soil at different doses were obtained.The apparent porosity of soil at different concentrations was obtained by using Scanning Electron Microscopy(SEM).[Results]The optimal enhancement in shear strength is achieved with the addition of 15 g/kg calcium sulfate,resulting in a 9.04％increase under a 300 kPa vertical load.As the dosage increases,the soil cohesive force sequentially increases by 27.24％,53.57％,and 49.39％compared to the control treatment.The change in the internal friction angle of the ameliorated soil is not significant,but it exhibits a trend of initial reduction followed by an increase with increasing application concentration,consistently lower than the blank control,decreasing by 8.73％,17.35％,and 3.91％,respectively.The addition of calcium sulfate promotes the formation of large aggregates in the soil and changes the microstructure of the detrital layer soil.With the addition of low concentration calcium sulfate,the soil particles are mainly in the form of large blocks and flakes,and the distance between each particle is far and the porosity is large.When the addition amount is 15 g/kg,the soil forms a special stacked book page structure,and as the application concentration increases,the apparent porosity of the soil decreases by 15％,25％,and 47.5％,respectively.[Conclusion]In summary,adding calcium sulfate can increase the mechanical strength of soil in the debris layer,which has important guiding significance for the Benggang management.关键词
土壤侵蚀/土壤改良剂/直剪试验/扫描电子显微镜/崩岗Key words
soil erosion/soil amendment/direct shear test/SEM/Benggang分类
农业科技引用本文复制引用
李晓非,张越,吴云博,杨璐,林金石,蒋芳市,葛宏力,黄炎和..添加硫酸钙对崩壁碎屑层土壤抗剪强度的影响[J].水土保持研究,2024,31(6):161-167,7.基金项目
国家自然科学基金(41907043) （41907043）
福建省科技创新项目资金(KY-090000-04-2021-001) （KY-090000-04-2021-001）
福建农林大学科技创新专项基金(CXZX2020075A) （CXZX2020075A）
