应力状态下含黏粗粒土渗透变形特性试验研究

发布时间：2018-03-04 02:24

本文选题：粗粒土　切入点：渗透变形特性　出处：《岩土工程学报》2014年01期 　论文类型：期刊论文

【摘要】：含黏粗粒土的渗透变形问题是水电工程中常见的渗透稳定性问题之一。对于含黏粗粒土来说,黏粒含量、颗粒级配及应力状态是影响渗透变形最重要的3个因素。为研究应力状态大小对含黏粗粒土渗透变形特性及临界水力梯度的影响,利用大直径渗透变形仪加载系统,完成了侧限条件下某含黏粗粒土在0.1,0.3,0.6,0.9 MPa铅直应力作用下的渗透变形试验。试验结果表明:不同应力状态下黏粒含量值的大小直接影响到含黏粗粒土的渗透变形破坏类型;试件中附加应力值越大,产生渗透变形时的临界水力梯度也越大。通过对渗透变形试验过程中渗透系数的演化过程研究,提出了利用渗透系数与水力梯度关系曲线的突变关系来判断临界水力梯度的新方法。
[Abstract]:The seepage deformation problem of clay coarse grained soil is one of the common seepage stability problems in hydropower engineering. For the clay coarse grained soil, the clay content, Particle gradation and stress state are the three most important factors affecting permeability deformation. In order to study the effect of stress state on permeability deformation characteristics and critical hydraulic gradient of clay and coarse grained soil, a large diameter osmotic deformator loading system is used. The permeation deformation test of a clay containing coarse grained soil under the action of 0. 1 ~ 0. 3 ~ 0. 3 ~ 0. 6 ~ 0. 9 MPa vertical stress has been completed. The results show that the content of clay in different stress states has a direct effect on the failure type of permeability deformation of the clay-containing coarse grained soil. The larger the additional stress in the specimen is, the larger the critical hydraulic gradient is when the seepage deformation occurs. A new method for judging critical hydraulic gradient is proposed by using the abrupt relation between permeability coefficient and hydraulic gradient curve.
【作者单位】：长沙理工大学水利工程学院;中国水电顾问集团中南勘测设计研究院水能资源利用关键技术湖南省重点实验室;
【基金】：“十二五”科技支撑计划课题(2012BAK03B04) 中国水电工程顾问集团科技计划项目(CHC-KJ-2008-08-02)
【分类号】：TU411.4

【参考文献】