土工基础

›› 2018, Vol. 32 ›› Issue (5): 567-570.

• 工程实录 • 上一篇    

不同渗透压力条件下黏质粉土的渗透试验研究

王 沛1，石 磊2,姚远宏1   

  1. (1.天津城建大学地质与测绘学院，天津 300384；2.天津市建设工程技术研究所，天津 300000)
  • 收稿日期:2018-09-03 修回日期:2018-09-06 出版日期:2018-10-30 发布日期:2018-11-02
  • 作者简介:王 沛（1973-），男，本科，副研究员，研究方向为土工试验和原位测试。
  • 基金资助:

    天津市建交委科技术项目（201512）；天津市高等学校科技发展基金计划项目( 20120911)；横向资助项目（hx201720）

Permeability Tests of Clayey Silt under Different Seepage Pressures

WANG Pei1, SHI Lei2, YAO Yuanhong1   

  1. (1.School of Geology and Geomatics, Tianjin Chengjian University, Tianjin 300384;
    2.Tianjin Construction Engineering Technology Research Institute, Tianjin 300300)
  • Received:2018-09-03 Revised:2018-09-06 Online:2018-10-30 Published:2018-11-02

摘要： 黏质粉土的渗透性能介于黏土与粉砂之间，在常规渗透试验中所获得的渗透系数有一定的不确定性，给基坑工程降水带来不良的影响。以天津主城区的黏质粉土层为研究对象，开展原状土样的固结渗压试验与三轴渗压试验。在不同渗透压力条件下，改变固结压力与渗透路径，分别测定土的渗透系数，分析固结压力、渗透压力与渗透路径对土的渗透性能的影响。试验结果证实，土的竖直渗透系数与水平渗透系数随固结应力的增加而减小，当固结压力大于上覆土的有效压力时，土的渗透性能变化明显。固结压力对土的渗透能力影响最为显著，而渗透路径的影响相对较小。

关键词: 黏质粉土, 渗透系数, 渗透压力, 固结压力, 渗透路径

Abstract: The permeability of clayey silt is between that of clay and silty sand. The coefficient of permeability obtained by the conventional permeability test does not consistent with the field performance which might result in an adverse effect on the dewatering for the deep excavation. This paper presents a case history of permeability tests on undisturbed clayey silt soils in consolidometers and triaxial cells. The coefficients of permeability obtained under different seepage pressures, consolidation pressures and seepage paths are evaluated, and their effects are compared. The results indicate that the magnitude coefficients of permeability in the vertical and horizontal directions reduces with the increase of consolidation pressure. When the consolidation pressure is greater than the effective overburden pressure, the coefficient of permeability demonstrates a strong relationship with the consolidation pressure and the impact of seepage path is relatively small.

Key words: Clayey Silt, Coefficient of Permeability, Seepage Pressures, Consolidation Pressure, Seepage Path