基于格子Boltzmann方法的土石混合体的渗流特性研究  

Seepage characteristics of soil-rock mixture based on lattice Boltzmann method

作　　者：金磊 曾亚武[2] 程涛 李晶晶 JIN Lei;ZENG Ya-wu;CHENG Tao;LI Jing-jing(School of Civil Engineering and Architecture,Hubei Polytechnic University,Huangshi 435003,China;School of Civil Engineering,Wuhan University,Wuhan 430072,China)

机构地区：[1]湖北理工学院土木建筑工程学院,湖北黄石435003 [2]武汉大学土木建筑工程学院,湖北武汉430072

出　　处：《岩土工程学报》2022年第4期669-677,I0005,共10页Chinese Journal of Geotechnical Engineering

基　　金：湖北省自然科学基金项目(2019CFB199);国家自然科学基金项目(41272342,12002121);湖北省高等学校优秀中青年科技创新团队计划项目(T201823)。

摘　　要：为了探究土石混合体的渗流特性,基于颗粒离散元法和三维离散元模型虚拟切片技术建立了土石混合体的三维随机孔隙结构模型并将其体素化,引入三维格子Boltzmann方法从孔隙尺度对其渗流开展了模拟,并据此分析了块石含量、相对密实度和块石粒径对土石混合体渗透率的影响,最后探讨了不同条件下块石含量对土石混合体渗透率存在不同影响的内在机制。研究结果表明:当相对密实度和块石粒径不变时,随块石含量增加,土石混合体的渗透率总体上是逐渐增大的,且增大的速率越来越大;相对密实度越高,土石混合体的渗透率越低;块石粒径对土石混合体的渗透率存在一定程度的影响,当块石含量小于临界值时,块石粒径越大则渗透率越小,而当块石含量高于临界值时,块石粒径越大则渗透率越大;当土石混合体中土体的密度保持不变时,其渗透率随块石含量增加先减小后增大。In order to explore the seepage characteristics of soil-rock mixture(SRM),random pore-structural models of SRM are constructed and voxelized based on the discrete element method and the proposed virtual slicing technique for three-dimensional discrete element model.Then,the three-dimensional lattice Boltzmann method is introduced to conduct a series of numerical simulations of the seepage flow in SRM from the pore scale,and the influences of rock content,rock size,relative density on the simulated permeability of SRM are comprehensively investigated.Finally,the internal mechanism of the influences of rock content on the permeability of SRM under different conditions is discussed.The results show that when the relative density and rock size both remain unchanged,the permeability of SRM presents a gradually increasing trend with the increase of rock content,and the increasing rate also increases.When other conditions remain unchanged,the permeability of SRM decreases with the increase of relative density.When the rock content is lower than a threshold value,the permeability decreases as the rock size increases,while this trend gets reversed when the rock content exceeds the threshold value.When the density of soils in SRM remains unchanged,the permeability of SRM decreases first and then increases with the increase of rock content.

关 键 词：土石混合体 格子BOLTZMANN方法 渗流特性 渗透率 孔隙尺度模拟 

分 类 号：TU411[建筑科学—岩土工程]