不同干密度下黄土孔隙分形特征及其对基质吸力的影响  

Pore Fractal Characteristics of Loess at Different Dry Densities and Their Influence on Matrix Suction

作　　者：童富果 李华翔[1,2] 薛松 李苗苗 TONG Fu-guo;LI Hua-xiang;XUE Song;LI Miao-miao(Hubei Key Laboratory of hydropower engineering construction and management,China Three Gorges University,Yichang 443002,Hubei Province,China;College of Hydraulic and Environmental Engineering,China Three Gorges University,Yichang 443002,Hubei Province,China)

机构地区：[1]三峡大学湖北省水电工程施工与管理重点实验室,湖北宜昌443002 [2]三峡大学水利与环境学院,湖北宜昌443002

出　　处：《中国农村水利水电》2024年第4期1-6,14,共7页China Rural Water and Hydropower

基　　金：国家自然科学基金青年项目(52209135);国家自然科学基金重点项目(51939004);湖北省自然科学基金一般面上项目(2022CFB337)。

摘　　要：基于分形几何学方法建立了土体孔径分布的描述,并结合Young-Laplace理论提出了考虑孔隙分形特征的非饱和土基质吸力模型。针对陕西地区的黄土收集了不同干密度的土水特征曲线并分析了干密度对孔隙分布特征及基质吸力的影响。结果表明:黄土孔隙具有明显分形特性,可采用Menger海绵体分形模型良好描述。模型孔隙特征参数分析发现随着干密度增大,分形维数D近似线性增大,而最大孔径L呈幂函数减小;通过函数拟合,进一步建立黄土孔径分布与干密度的特征关系,进而实现了对不同干密度下的黄土基质吸力快速预测。Based on fractal geometry,the description of soil pore size distribution is established,and a suction model of unsaturated soil ma⁃trix considering the fractal characteristic of pores is proposed in combination with Young-Laplace theory.For the loess in Shaanxi region,the soil-water characteristic curves of different dry densities were collected,and the effects of dry density on pore distribution characteristics and matrix suction were analyzed.The results show that the loess pores have obvious fractal properties,which can be well described by the Menger Sponge fractal model.The pore fractal model parameter analysis shows that with the increase of dry density,the fractal dimension D increases approximately linearly,while the maximum aperture L decreases as a power function.Through function fitting,the characteristic re⁃lationship between loess pore size distribution and dry density is further established,and the suction capacity of loess matrix suction under different dry densities is quickly predicted.

关 键 词：基质吸力 黄土 孔径分布 分形模型 干密度 

分 类 号：TV16[水利工程] TU444[建筑科学—岩土工程]