Behavior of unsaturated sandy loess under high-frequency unilateral cyclic loading
Zhenwei Jiang1, Bingyan Shen2, Jiaqing Gao1
1College of Geological Engineering and Surveying, Chang'an University, Xi'an, China.
Scientific Reports
|August 26, 2025
Summary
Sandy loess is prone to destabilization under cyclic loads, especially in China
Area of Science:
- Geotechnical Engineering
- Soil Mechanics
- Environmental Geology
Background:
- Sandy loess soils are susceptible to structural failure under cyclic loading.
- Recurrent geotechnical failures have been observed in hydrocarbon extraction zones on China's Loess Plateau.
- The Maliancheng Village landslide highlights the risks associated with these soil types.
Purpose of the Study:
- To investigate the moisture-dependent and frequency-governed mechanical behaviors of unsaturated sandy loess.
- To understand the factors contributing to geotechnical failures in Loess Plateau extraction zones.
Main Methods:
- Cyclic triaxial testing was employed to analyze soil behavior.
- The study evaluated stress-strain hysteresis, shear rigidity, and energy dissipation.
- Effects of moisture content and loading frequency were examined.
Main Results:
- Moisture content beyond the plastic limit had minimal impact on mechanical properties.
- Sub-plastic-limit moisture content increased damping ratios and decreased shear resistance.
- Higher loading frequencies led to increased strain magnitude and shear stiffness, but decreased damping.
Conclusions:
- Sandy loess behavior under cyclic loading is complex and influenced by moisture and frequency.
- Understanding these factors is crucial for mitigating landslide risks in extraction zones.
- Further research into high-rate cyclic load effects on soil stabilization is warranted.
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