动水作用下岩体裂隙中颗粒运动规律的试验研究  

xperimental study on motion law of particles in rock fissures under dynamic water action

作　　者：崔溦[1,2,3] 裴介渲 江志安[4] CUI Wei;PEI Jie-xuan;JIANG Zhi-an(State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation,Tianjin University,Tianjin 300072,China;Key Laboratory of Earthquake Engineering Simulation and Seismic Resilience of China Earthquake Administration,Tianjin University,Tianjin 300072,China;School of Civil Engineering,Tianjin University,Tianjin 300072,China;Tianjin Key Laboratory of Ground and Foundation Engineering,Sinohydro Foundation Engineering Co.,Ltd.,Tianjin 301700,China)

机构地区：[1]天津大学水利工程智能建设与运维全国重点实验室,天津300072 [2]天津大学中国地震局地震工程综合模拟与城乡抗震韧性重点实验室,天津300072 [3]天津大学建筑工程学院,天津300072 [4]中国水电基础局有限公司天津市地基与基础工程企业重点实验室,天津301700

出　　处：《岩土力学》2024年第10期2870-2878,共9页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.52079092)。

摘　　要：动水作用下岩体裂隙中的颗粒运动是引起渗透破坏的常见原因。针对天然岩石裂隙的随机性与隐蔽性,采用三维Weierstrass-Mandelbrot分形函数构建随机裂隙通道,并采用3D打印方法获得透明裂隙模型实体,使用微流体控制仪开展动水作用下颗粒在裂隙中的运动试验,分析裂隙粗糙程度、颗粒粒径与裂隙开度的比值(简称粒径隙宽比)、渗流水压力对颗粒在裂隙中起动、运移的影响规律,进而推断岩体裂隙发生渗透破坏的可能性。研究结果表明:颗粒在岩石裂隙中的运动规律与裂隙粗糙程度、水压力、颗粒粒径隙宽比3个因素有关。裂隙粗糙程度越大,或颗粒粒径隙宽比越大,颗粒越不容易开始运动,即裂隙发生渗透破坏的可能性越低。同时,水压力是颗粒运动的主导因素,颗粒粒径隙宽比对颗粒运动的影响与水压力有关。存在一特定水压力临界值,未达到该水压力时,颗粒粒径隙宽比对平均运动速度的影响不明显,超过该水压力后,影响程度显著增大,且该临界水压力值的大小与裂隙粗糙程度有关,裂隙越粗糙,临界水压力越大。Particle movement in rock fissures,influenced by dynamic water action,often leads to infiltration damage.To address the random and hidden nature of natural rock fissures,a fissure channel with a rough joint surface was constructed using a three-dimensional Weierstrass-Mandelbrot fractal function.A transparent and refined fracture channel was obtained using 3D printing technique,and the movement of particles in the fissures under the action of moving water was studied using microfluidic control instruments.The influences of the degree of fissure roughness,the ratio of particle size to fissure width(it is referred to“particle-to-gap size rate”in text),and the seepage pressure on particle initiation and transport were analyzed to deduce the possibility of infiltration damage in rock.The results show that of particle movement in rock fissures is related to three factors:the degree of fissure roughness,the water pressure,and the particle-to-gap size rate.Larger fissure roughness or larger particle-to-gap size rate makes particle movement less likely,reducing the possibility of seepage failure.At the same time,the water pressure is the dominant factor in particle movement,the impact of particle-to-gap size rate on particle movement is related to water pressure.There is a specific water pressure critical value.Below this value,the influence of particle-to-gap size rate on average movement speed is not obvious.Beyond this value,the influence increases significantly.The critical water pressure value is related to the degree of fissure roughness.The rougher the fissure,the higher the critical water pressure.

关 键 词：岩体裂隙 颗粒运动 动水压力 分形维数 室内试验 

分 类 号：TU452[建筑科学—岩土工程]