Effect of clay content on shear strength of loess

Authors

WANG Li, Key Laboratory of Mine Geological Hazards Mechanism and Control, Xi'an 710054, China; School of Geological Engineering and Geomatics, Chang'an University, Xi'an 710054, China
LI Xi'an, School of Geological Engineering and Geomatics, Chang'an University, Xi'an 710054, China; Open Research Laboratory of Geotechnical Engineering, Ministry of Land and Resources, Xi'an 710054, ChinaFollow
HONG Bo, Key Laboratory of Mine Geological Hazards Mechanism and Control, Xi'an 710054, China; School of Geological Engineering and Geomatics, Chang'an University, Xi'an 710054, China
DU Shaoshao, Key Laboratory of Mine Geological Hazards Mechanism and Control, Xi'an 710054, China
ZHANG Hangbo, Key Laboratory of Mine Geological Hazards Mechanism and Control, Xi'an 710054, China
ZHAO Ning, School of Geological Engineering and Geomatics, Chang'an University, Xi'an 710054, China

Abstract

The experimental research about effect of different clay content on shear strength of loess was carried out to reveal the influence of clay content on shear strength and its microscopic mechanism, and then a scientific basis for engineering practice of loess was provided. Self-made wet sieve device under negative pressure was applied to screen loess samples with different clay content. Different clay content of the loess samples were made to the same dry density, but with different moisture content using static pressure method, and then were taken direct shear test. The results show that with the increase of moisture content, the cohesion of samples with different clay content firstly increased and then decreased, and reached the maximum near 14%, while the friction angle showed a monotonic downward trend. With the increase of clay content, the cohesion showed a rising trend, while the friction angle first decreased and then increased. The effect of clay content on shear strength of loess can be explained by its microstructure.

Keywords

clay content, water content, shear strength, cohesion, internal friction angle, microstructure

DOI

10.3969/j.issn.1001-1986.2019.03.028

Recommended Citation

WANG Li, LI Xi'an, HONG Bo, et al. (2019) "Effect of clay content on shear strength of loess," Coal Geology & Exploration: Vol. 47: Iss. 3, Article 29.
DOI: 10.3969/j.issn.1001-1986.2019.03.028
Available at: https://cge.researchcommons.org/journal/vol47/iss3/29

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