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Volume 35 Issue 1
Feb 2024
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Article Contents
Lina Ma, Shengwen Qi, Songfeng Guo, Qiangbing Huang, Xiaokun Hou. Investigation on the Deformation and Failure Patterns of Loess Cut Slope Based on the Unsaturated Triaxial Test in Yan'an, China. Journal of Earth Science, 2024, 35(1): 235-247. doi: 10.1007/s12583-021-1554-4
Citation: Lina Ma, Shengwen Qi, Songfeng Guo, Qiangbing Huang, Xiaokun Hou. Investigation on the Deformation and Failure Patterns of Loess Cut Slope Based on the Unsaturated Triaxial Test in Yan'an, China. Journal of Earth Science, 2024, 35(1): 235-247. doi: 10.1007/s12583-021-1554-4

Investigation on the Deformation and Failure Patterns of Loess Cut Slope Based on the Unsaturated Triaxial Test in Yan'an, China

doi: 10.1007/s12583-021-1554-4
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  • Corresponding author: Shengwen Qi, qishengwen@mail.iggcas.ac.cn
  • Received Date: 04 Aug 2021
  • Accepted Date: 24 Sep 2021
  • Issue Publish Date: 29 Feb 2024
  • The large-scale implementation of the Gully Stabilization and Land Reclamation (GSLR) project induces various failures of loess slopes due to excavation in Yan'an, China. However, the deformation and failure behavior of these excavated loess slopes have not been fully understood. In this study, field investigation was undertaken for analyzing the distributions and failure features of excavation-induced loess slope failures. It is found that plastic failure mainly occurs in Q3 loess layers and brittle failure in Q2. To understand the underlying failure mechanism, a series of triaxial shear tests were conducted on intact Q3 and Q2 loess samples that with different water contents, namely natural water content (natural), dry side of the natural value (drying 5%), and wet side (wetting 5%). The characteristics of stress-strain curves and failure modes of the samples were analyzed. Results show that the stress-strain curves of Q2 samples are dominated by strain-softening characteristics, while Q3 samples mainly exhibit strain-harden features except in the drying state. Correspondingly, shear failures of Q3 specimens are mainly caused by shear crack planes (single, X or V-shaped). For Q2 loess, the dominance of tensile cracks is observed on the surface of damaged specimens. These disclose the different failure modes of excavated slopes located in different strata, that is, the arc sliding failure of Q3 loess slopes and the stepped tensile failure of Q2 loess slopes, and are helpful in the design and management of the ongoing GSLR projects in the Loess Plateau.

     

  • Conflict of Interest
    The authors declare that they have no conflict of interest.
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