岩土力学2024，Vol.45Issue(1)：302-312,11.DOI:10.16285/j.rsm.2023.0163
各向异性砂土渗流潜蚀流体动力学-离散元流固耦合分析
Computational fluid dynamics-discrete element fluidsolid coupling analysis on suffusion in anisotropic sandy soils
摘要
Abstract
For the problem of suffosion in gap-graded sand with initial anisotropy,the Ganser drag force model,which can take into account the effect of the projected area of particles,is introduced to achieve a two-phase coupling of computational fluid dynamics(CFD)and discrete elements method(DEM)for non-spherical particles.The applicability of the numerical method in solving the interaction between the non-spherical particles and fluid is verified by comparing with single particle settlement tests.On this basis,specimens with different bedding orientations and fine contents are further generated to simulate upward seepage suffosion tests,during which both macroscopic and microscopic properties,such as the fine loss,composition of strong and weak force chains,and changes in grain fabric,are monitored to explore the seepage suffosion characteristics of anisotropic soils with various fabrics under different filling states(underfilled and overfilled).Drained triaxial tests are carried out on specimens before and after erosion to investigate the effect of seepage on the weakening of soil strength.The results show that the mass loss of the overfilled specimens increases with increasing bedding angle,while the mass loss of the underfilled specimens firstly increases and then decreases with the bedding angle.The loss of fines in the underfilled specimens is mainly due to the low connectivity fines,whereas for the overfilled specimens,suffosion leads to a simultaneous reduction in the number of both low and high connectivity fines.In addition,the triaxial tests show that suffusion causes a signifiicant weakening of the peak strength of the soil,and the change in peak strength with the bedding angle is also influenced by the soil filling state.关键词
CFD-DEM/渗流潜蚀/异形颗粒/拖曳力模型/各向异性/微观组构Key words
CFD-DEM/suffosion/non-spherical particles/drag force model/anisotropy/microscopic fabric分类
建筑与水利引用本文复制引用
周闯,钱建固,尹振宇..各向异性砂土渗流潜蚀流体动力学-离散元流固耦合分析[J].岩土力学,2024,45(1):302-312,11.基金项目
国家自然科学基金项目(No.52178345).This work was supported by the National the Natural Science Foundation of China(52178345). （No.52178345）
