不同含液量下颗粒间液桥力及形态的试验研究  

Experimental study on liquid force and profile between two moving sphere particles under different liquid content condition

作　　者：蒲诚 刘奉银[1] 张昭[1] 程靖轩 赵伟 PU Cheng;LIU Fengyin;ZHANG Zhao;CHENG Jingxuan;ZHAO Wei(Institute of Geotechnical Engineering,Xi’an University of Technology,Xi’an 710048,China)

机构地区：[1]西安理工大学岩土工程研究所,陕西西安710048

出　　处：《水利学报》2020年第1期81-91,共11页Journal of Hydraulic Engineering

基　　金：国家自然科学基金项目(51679198,41372304,41877278,41402258)。

摘　　要：对液桥力的研究有助于从根本上揭示非饱和土持水特性的内在机理。以等径球体颗粒间的液桥为研究对象,利用纳米多功能试验机及CCD数码相机分别测量并记录了三种粒径、六种含液量下液桥拉伸过程中力值及形态的变化,并将试验结果与理论计算结果进行对比,同时对不同类型液桥拉伸曲线产生的原因提出了猜想。结果表明:液桥力-位移曲线可以分为上升段、平稳下降段以及突然跌落段三部分;不同含液量下液桥的初始形态不同,钟摆状液桥主要出现在饱和度较低且重力影响可以忽略的条件下,随着饱和度的增加液桥初始形态变为圆柱状以及外凸状;最大液桥力与粒径及含液量成正比,断裂距离与含液量成正比与粒径成反比,且粒径对最大液桥力以及断裂距离的影响更为显著;不同研究者观测到的两类液桥力-位移曲线可能是试验初始点不同导致的。The study on liquid bridge is helpful to reveal the inner mechanism of water retention properties of unsaturated soil.Taking the liquid bridge between equal particles as object,the force value and profile change of liquid bridge under three particle diameters and six liquid contents were measured and recorded by using Nano UTM and CCD camera,and the test results were compared with the theoretical calculation results.Meanwhile,the supposition of different types of tensile curves was proposed.The results show that the tensile curve can be divided into ascent stage,descent stage and rupture stage,respectively,and the initial profile is various under different liquid content condition,the pendular occurs only when the satura⁃tion is extremely small and the influence of gravity can be neglected,with the rising of liquid volume,the initial profile turn into cylindrical and convex.In addition,the maximum liquid force increase with the ris⁃ing of particle size and the liquid content,while the rupture distance increase with the increase of liquid content and decrease of particle size,the influence of particle size on the maximum force and the rupture distance is more significant.Finally,different kinds of curves are caused by the discrepancy of starting point during experiment.

关 键 词：非饱和土 持水特性 液桥拉伸 试验研究 

分 类 号：TU43[建筑科学—岩土工程]