Microstructural evolution of compacted loess during consolidation and shearing

XIAO Tao; LI Ping; SHAO Sheng-jun

doi:10.11779/CJGE2021S1018

Volume 43 Issue S1

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Chinese Journal of Geotechnical Engineering > 2021 > 43(S1): 99-104. > DOI: 10.11779/CJGE2021S1018

XIAO Tao, LI Ping, SHAO Sheng-jun. Microstructural evolution of compacted loess during consolidation and shearing[J]. Chinese Journal of Geotechnical Engineering, 2021, 43(S1): 99-104. DOI: 10.11779/CJGE2021S1018

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Microstructural evolution of compacted loess during consolidation and shearing

XIAO Tao^1,,
LI Ping^{1, 2, ,},
SHAO Sheng-jun²

1.
State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi'an 710069, China
2.
Shaanxi Key Laboratory of Loess Mechanics and Engineering, Xi'an 710048, China

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Received Date: December 28, 2020
Available Online: December 05, 2022

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Abstract

Abstract

To understand the microstructural evolution of compacted loess during consolidation and shearing, the triaxial tests and the MIP technology are used to acquire the pore-size distribution curve of compacted loess specimens with different stress and strain states.By analyzing the pore-size distribution characteristics of compacted loess specimens, the microstructural evolution of compacted loess during consolidation and shearing is studied.The results show that the compacted loess tested is strongly contractive during shearing, and the evolution of the pore-size distribution of compacted loess during consolidation is similar to that during shearing.The intra-aggregate pores are not affected, only the inter-aggregate pores are compressed.In addition, based on the pore-size distribution curve, the fractal dimension of each specimen is calculated by the fractal theory, which changes a little from specimen to specimen.It is indicated that the roughness of pore surface changes little during the process of consolidation and shearing, and there is no obvious correlation between fractal dimension, void ratio and axial strain.The research results indicate that the mechanical response of compacted loess is due to the interaction between aggregates, while not between particles.
- compacted loess,
- evolution of microstructure,
- pore-size distribution curve,
- mechanical response,
- fractal dimension

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References (21)

References

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