4.7 Article

Failure mechanisms of sand under asymmetrical cyclic loading conditions: experimental observation and constitutive modelling

Journal

GEOTECHNIQUE
Volume 72, Issue 2, Pages 162-175

Publisher

ICE PUBLISHING
DOI: 10.1680/jgeot.20.P.004

Keywords

anisotropy; constitutive relations; failure; laboratory tests; liquefaction; sands

Funding

  1. Natural Science Foundation of China [51908502, 51825803]
  2. China Postdoctoral Science Foundation [2020M671788]

Ask authors/readers for more resources

In this study, comprehensive asymmetrical cyclic loading tests were conducted to investigate the liquefaction responses of sand. The results showed that different stress conditions can lead to three distinct failure mechanisms. By developing an anisotropic sand model, the typical deformation, strength, and fabric characteristics of sand under different cyclic failure mechanisms could be accurately captured.
In practical engineering, natural soil deposits often sustain an initial driving force prior to cyclic shear, owing to earthquakes, traffic and waves; such asymmetrical loading conditions may significantly affect the liquefaction susceptibility and failure mechanism of sand. To understand the typical cyclic liquefaction responses, comprehensive asymmetrical cyclic loading tests were conducted on sand samples subjected to either compressional or extensional static stress. The results indicated that different stress conditions can result in three distinct failure mechanisms: flow liquefaction, cyclic mobility and residual deformation accumulation. According to the experimental observations, an anisotropic sand model was developed within the framework of the anisotropic critical state theory. The model employed a fabric-dependent dilatancy, and accounted for the effects of the fabric evolution and accumulated loading index on the plastic hardening, in order to better reflect the cyclic degradation of the plastic modulus. The predictive capacity of the model was confirmed through undrained monotonic test results for samples with different densities. Comparisons between the model responses and experimental results indicated the excellent capabilities of the developed model in terms of capturing the typical deformation, strength and fabric characteristics of different cyclic failure mechanisms of sand under either symmetrical or asymmetrical loading conditions.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.7
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available