泥水盾构排浆管砾石沉积特性及对泥浆影响规律  

Sedimentation characteristics of gravel in discharge pipe of slurry shield tunneling and its impact on slurry

作　　者：李振 邓朝辉[2] 李树忱[1,4] 袁超 彭科峰[1,3] LI Zhen;DENG Chaohui;LI Shuchen;YUAN Chao;PENG Kefeng(Geotechnical and Structural Engineering Research Center of Shandong University,Ji'nan 250012,China;China Railway Fourth Survey and Design Institute Group Co.,Ltd.,Wuhan 430063,China;Qilu Jiaotong College of Shandong University,Ji'nan 250061,China;School of Mechanics and Civil Engineering,China University of Mining and Technology,Xuzhou 221116,China;School of Civil Engineering and Water Resources,Shandong University,Ji'nan 250062,China)

机构地区：[1]山东大学岩土与结构工程研究中心,山东济南250012 [2]中铁第四勘察设计院集团有限公司,湖北武汉430063 [3]山东大学齐鲁交通学院,山东济南250061 [4]中国矿业大学力学与土木工程学院,江苏徐州221116 [5]山东大学土建与水利学院,山东济南250062

出　　处：《岩土工程学报》2025年第4期849-859,共11页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金项目(52108373);济南市“高校20条”资助项目(2020GXRC046);黏性地层土压平衡盾构黏附堵塞机理与化-电协同改良机制研究项目(52478399)。

摘　　要：为研究泥水盾构掘进风化岩层时排浆管内砾石的输送特性,基于CFD-DEM方法建立排浆管砾石输送模型,分析砾石输送过程中的速度分布、受力特征、运动形式,以及砾石床层对泥浆流动的影响规律,研究砾石尺寸、砾石形状、泥浆流速和泥浆相对质量密度对砾石沉积特性的影响。研究表明,砾石颗粒以沙丘状床层间歇式推移。砾石速度沿高度分层,表层砾石速度快,运动以碰撞和滚动为主;近壁层砾石速度慢,运动以滑移为主。近壁层和表层砾石间存在过渡层。砾石床层使管道内泥浆流速和压力局部增大。砾石床层速度随泥浆流速增大呈现线性增大。砾石床层高度随砾石尺寸增大而增大。泥浆相对质量密度越大,砾石受到曳力越大。砾石形状系数越小,输送难度越大。建立砾石沉积风险评价指标,通过传速系数α和增压系数β对砾石沉积风险评价,并提出针对性调控方法,为预防和处理砾石沉积堵塞提供参考。The slurry shield tunneling in weathered rock layers is prone to gravel accumulation within the slurry pipe.In order to study the transportation characteristics of gravel in the slurry pipe,a model of gravel transportation in the slurry pipe of the shield tunneling was established based on the computational fluid dynamics-discrete element(CFD-DEM)coupling method.The rheological characteristics of the slurry were considered through the rheological tests,and the accuracy of the model is verified through the gravel sedimentation tests.The velocity distribution,force characteristics and motion forms of gravel during transportation as well as the influences of gravel bed deposition on the slurry were analyzed.The effects of gravel size,gravel shape,slurry flow rate and slurry density on the sedimentation characteristics of gravel are explored.This study indicates that gravel particles move intermittently in a sand dune-like bed.The gravel velocity is layered along the height,and the surface gravel velocity is fast,with collision and rolling as the main movements.The velocity of gravel in the near wall layer is slow,and its movement is mainly dominated by sliding.There is a transition layer between the near wall layer and the surface gravel layer.The gravel bed layer locally increases the flow velocity and pressure of the slurry in the pipeline.The velocity of the gravel bed increases linearly with the increase of the slurry flow rate.The height of the gravel bed increases with the size of the gravel.The higher the density of the slurry,the greater the drag force on the gravel.The smaller the gravel shape factor,the greater the difficulty of transportation.Finally,the risk assessment indices are established for gravel sedimentation,and the targeted control methods are proposed to provide reference for preventing and treating sedimentation blockage of gravel.

关 键 词：泥水盾构 CFD-DEM耦合 砾石输送 沉积堵塞 颗粒床推移 

分 类 号：TU443[建筑科学—岩土工程]