基于3个不等粒径非接触颗粒模型的土-水特征曲线  

Soil-water characteristic curves based on the non-contact case of three particles of unequal size

作　　者：王文东[1] 刘小文[1] WANG Wendong;LIU Xiaowen(School of Infrastructure Engineering,Nanchang University,Nanchang 330031,China)

机构地区：[1]南昌大学工程建设学院,江西南昌330031

出　　处：《南昌大学学报（工科版）》2023年第1期38-43,58,共7页Journal of Nanchang University(Engineering & Technology)

基　　金：国家自然科学基金项目(51268046、52169026)。

摘　　要：颗粒级配及孔隙结构对非饱和土的土-水特征曲线影响较大,传统的土-水特征曲线模型多采用试验数据建立,难以揭示颗粒级配及颗粒间接触情况等因素的影响。将黏土团颗粒视为规则圆颗粒,基于热力学原理及二维液桥计算模型,以3个不同直径的非接触黏土团颗粒为研究对象,建立反映非饱和土的微观结构的3个不同直径的非接触式颗粒模型,从微观角度探究土-水特征曲线,讨论了颗粒间间距、颗粒级配以及颗粒粒径等因素对土-水特征曲线的影响。结果表明:与颗粒接触组对比发现,土-水特征曲线的特征值均随着粒间距的增大而增大,等间距的情况下相应的增长趋势却存在一个峰值;在饱和度一定的情况下,不均匀系数与基质吸力呈反相关关系;在基质吸力相同的情况下,最大粒径越小则饱和度就越高。Particle gradation and pore structure have a large influence on the soil-water characteristic curve of unsaturated soils.Traditional soil-water characteristic curve models were mostly built using experimental data,which was difficult to reveal the influence of factors such as particle gradation and inter-particle contact.The clay mass particles were regarded as regular circular particles,and based on the fractal theory,thermodynamic principle and two-dimensional liquid bridge calculation model,three non-contact clay mass particles of different diameters were used as the object of study to establish three non-contact particle models of different diameters reflecting the microstructure of unsaturated soil,to investigate the soil-water characteristic curve from the microscopic perspective,and to discuss the influence of inter-particle spacing,particle gradation and particle size on the soil-water characteristic curve.The results showed that,in comparison with the particle contact group,the eigenvalues of the soil-water characteristic curves all increased with increasing particle spacing,but there is a peak in the corresponding growth trend for equal spacing;for a certain degree of saturation,the inhomogeneity coefficient was inversely correlated with the matrix suction;for the same matrix suction,the smaller the maximum particle size,the higher the degree of saturation.

关 键 词：土-水特征曲线 颗粒间距 级配 粒径 

分 类 号：TU43[建筑科学—岩土工程]