河北水利电力学院学报 ›› 2023, Vol. 33 ›› Issue (3): 73-78.DOI: 10.16046/j.cnki.issn2096-5680.2023.03.012

• 岩土工程专题 • 上一篇    下一篇

季冻区路基非饱和土全吸力范围渗透规律研究

李霞   

  1. 河北省张家口市公路施工管理处,河北省张家口市经开区市府东大街11号 075000
  • 收稿日期:2022-10-20 修回日期:2022-11-19 出版日期:2023-09-30 发布日期:2023-10-26
  • 作者简介:李霞(1976-),女,河北保定人,高级工程师,主要从事道路工程勘查设计与施工。E-mail:1304343460@qq.com
  • 基金资助:
    张家口市重点研发计划项目(2221026B)

Effect of Freeze-thaw and Suction on Permeability of Unsaturated Soil

LI Xia   

  1. Highway Construction Management Office of Zhangjiakou City, 075000, Zhangjiakou, Hebei, China
  • Received:2022-10-20 Revised:2022-11-19 Online:2023-09-30 Published:2023-10-26

摘要: 冻融作用下非饱和土体渗透性的变化不仅受冻结负温、冻融次数等因素影响,试样的吸力大小也会影响土体渗透性的变化。为探究冻融循环和吸力作用下土体渗透系数的演化规律,将经历不同冻融循环次数的试件利用两种方式控制吸力,从而建立全吸力土-水特征曲线进行VG模型拟合,借助戈德纳经验公式计算全吸力条件下经历不同冻融次数的渗透系数变化规律。结果表明:全吸力土-水特征曲线随冻融循环次数的增加逐渐降低;通过研究发现在低吸力阶段渗透系数随吸力的变化有明显的分阶段性;同吸力下渗透系数随冻融次数的改变与孔隙率的改变呈现正相关;渗透系数的取值范围随冻融循环次数的增加逐渐增加,在3次冻融之后变化不明显。

关键词: 土-水特征曲线, 非饱和土, 蒸汽平衡法, 渗透系数, VG模型

Abstract: The change of unsaturated soil permeability under freeze-thaw action is not only affected by freezing negative temperature, freeze-thaw times and other factors, but also affected by suction of samples. To study the evolution law of soil permeability coefficient under freeze-thaw cycles and suction, the test piece will experience different times of freezing and thaw cycle to control suction in two ways to establish full suction soil-water characteristic curve for VG model fitting and calculate the permeability coefficient of different freeze and melting cycles within the range of full absorption. The results show that the full suction soil-water characteristic curve gradually decreases with the increase of the permeability in the low suction phase; the permeability coefficient and the permeability after three times and the permeability coefficient gradually decreases with the absorption.

Key words: soil-water characteristic curve, unsaturated soil, steam balance method, relative permeability coefficient, VG model

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