长江科学院院报 ›› 2021, Vol. 38 ›› Issue (1): 114-118.DOI: 10.11988/ckyyb.20200034

• 岩土工程 • 上一篇    下一篇

内部侵蚀砂土的三轴试验研究

杨阳1,2, 毛无卫1, 叶敏1   

  1. 1.同济大学 地下建筑与工程系,上海 200092;
    2.河海大学 水文水资源与水利工程科学国家重点实验室,南京 210098
  • 收稿日期:2020-01-10 修回日期:2020-04-29 出版日期:2021-01-01 发布日期:2021-01-27
  • 通讯作者: 毛无卫(1986-),男,江西玉山人,助理研究员,工学博士,研究方向为基础工程、地质灾害防治。E-mail: maowuwei@tongji.edu.cn
  • 作者简介:杨 阳(1988-),女,陕西西安人,工程师,工学博士,研究方向为土工测试技术、土体内部侵蚀。E-mail: 2011yang@tongji.edu.cn
  • 基金资助:
    国家自然科学基金项目(51609171);中央高校基本科研业务费专项资金项目(22120180625);水文水资源与水利工程科学国家重点实验室“一带一路”水与可持续发展科技基金项目(2019492311)

Triaxial Experiments on Sandy Soil Subjected to Internal Erosion

YANG Yang1,2, MAO Wu-wei1, YE Min1   

  1. 1. Department of Geotechnical Engineering, Tongji University,Shanghai 200092,China;
    2. State Key Laboratoryof Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing 210098, China
  • Received:2020-01-10 Revised:2020-04-29 Online:2021-01-01 Published:2021-01-27

摘要: 由管涌等水土内部侵蚀作用产生的贯通侵蚀孔道是土体结构破坏以及边坡、水坝、堤防等失稳的重要原因之一。利用溶解土样中预制水溶性化学添加物的方法在三轴试样中还原内部侵蚀效果,结合弯曲元测试系统,探讨初始密实度、围压对侵蚀后土体力学参数的影响。研究结果表明:随着侵蚀过程的加剧,砂土的剪切波速逐渐降低,且降低幅度随围压和密实度的增大而增加;相较于纯砂试样,侵蚀试样的峰值强度出现一定降低,但两者残余强度差别较小。土体的内部侵蚀发展过程较为复杂,利用葡萄糖粉末的溶解过程模拟细颗粒在渗流作用下被带出的管涌侵蚀作用,可以精确控制侵蚀产生和发展过程中孔隙通路的形成过程,为研究侵蚀后土体力学性质提供了新思路。

关键词: 砂土, 内部侵蚀, 弯曲元, 剪切波速, 抗剪强度, 三轴试验

Abstract: Internal erosion of soil resulted from piping, seepage or overtopping is found to be responsible for a large number of hydraulic structure failures. In this research, a method of preparing samples subjected to piping effect is achieved by dissolving water soluble material (glucose) in sandy soil. Qualitative impacts of initial density and confining pressure on the mechanical properties of the disturbed soil were investigated through triaxial compression tests and bender element tests under different initial densities and confining pressures. According to the test results, obvious reduction in shear wave velocity as well as peak shear strength was observed in the eroded specimen, and such reduction intensified along with the increasing of confining pressure and density, while residual strength appeared to be less affected.

Key words: sandy soil, internal erosion, bender element, shear wave velocity, shear strength, triaxial test

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