Thixotropic mechanism of clay: A microstructural investigation
Thixotropic mechanism of clay: A microstructural investigation
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粘土的触变机理：微观结构研究
DOI：
10.1016/j.sandf.2017.01.002
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发表时间：
2017-02
影响因子：
3.7
通讯作者：
Sayem H. M.
中科院分区：
文献类型：
--
作者：
Zhang X. W.;Kong L. W.;Yang A. W.;Sayem H. M.
高敏感性粘土表现出不同程度的触变特征。以前的研究主要集中在稀释悬浮液上，但只有少数研究调查了含水量低于液体极限的普通粘土。鉴于有限的研究，粘土的触变行为和潜在的机制仍然不明确，特别是在微观尺度上。本文以湛江粘土为研究对象，对触变过程进行了研究。将样品进行搅拌，然后进行无侧限抗压强度和口袋穿透测试，扫描电子显微镜和压汞孔隙率测试，以评估其恢复强度和微观结构。触变500d后，湛江黏土的强度比扰动后提高了2.58倍，显著高于文献报道的其他黏土。这些发现证明了触变性是通过颗粒运动引起的孔径分布均匀化，使分散结构转变为絮状结构的过程。这种现象可能是由于粒子间引力和斥力相互作用的变化。根据实验结果，提出了黏土的触变机理。该研究将有助于对扰动土的强度进行预测。
Clays with high sensitivity exhibit varied degrees of thixotropic characteristics. Previous research has been focused on dilute suspensions, but only a few studies have investigated normal clay with water contents lower than the liquid limit. Given the limited studies performed, the thixotropic behavior of clays and the underlying mechanism remain ambiguous, particularly in the microscopic scale. In this study, samples of Zhanjiang clay from southern China were used to elucidate the thixotropic process. The samples were agitated and then subjected to unconfined compressive strength and pocket penetrometer tests, scanning electron microscopy, and mercury intrusion porosimetry to evaluate their regain strength and microstructure. After 500 d of thixotropy, the strength of the Zhanjiang clay was 2.58 times higher than that after the disturbance and significantly higher than that of the other clays reported in the literature. These findings provide evidence that thixotropy is a process in which the dispersed structure is transformed into a flocculent structure through the homogenization of the pore size distribution caused by particle movement. This phenomenon may be due to the changes in the interaction of attractive and repulsive forces between particles. Given the experimental findings, a thixotropic mechanism for clay is proposed. This study will be beneficial for predicting the strength of disturbed soils.
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DOI：
10.1061/(asce)0733-9410(1991)117:9(1288
发表时间：
1991-09
期刊：
Journal of Geotechnical Engineering
影响因子：
--
作者：
J. Schmertmann
通讯作者：
J. Schmertmann
影响因子：
5.8
作者：
J. B. Hansen
通讯作者：
J. B. Hansen
影响因子：
6.5
作者：
W. Markgraf;R. Horn;S. Peth
通讯作者：
W. Markgraf;R. Horn;S. Peth
影响因子：
0.8
作者：
G. Kul'chitskii
通讯作者：
G. Kul'chitskii
影响因子：
4.9
作者：
M. Searle;Jon Cox
通讯作者：
M. Searle;Jon Cox