Effect of Soaking Time and Salt Concentration on Mechanical Characteristics of Slip Zone Soil of Loess Landslides
Abstract
:1. Introduction
2. Materials and Methods
2.1. Test Samples
2.2. Sample Preparation with Different Soaking Time
2.3. Sample Preparation with Different Salt Concentration
2.4. Sample Preparation with Different Soaking Time
2.5. Testing Program and Procedure
3. Testing Results
3.1. Effect of Soaking Time
3.2. Effect of NaCl Concentration
4. Changes of Surface Morphology and Microstructure of Loess Soils with Different Salt Contents
4.1. Changes of Surface Morphology
4.2. Changes of Microstructure of Loess Soils
5. Discussion
5.1. The Peak Shear Strength and Residual Strength
5.2. Implications for Loess Landslides
6. Conclusions
- (1)
- The shear behavior of loess soils is closely related to the soaking time, and the peak strength and residual strength decreases as the soaking time increases only up to a certain value. When this level is exceeded, any further increase of soaking time results in higher shear strengths.
- (2)
- The peak strength and residual strength increased with increasing salt concentration before reaching a maximum value at the salt concentration of 8%. Above this concentration, the peak strength and residual strength decrease with further increase in the salt concentration, and both strengths decreases to a relatively small value after about salt concentration of 16%.
- (3)
- The maximum difference between the peak strength and residual strength was attained with the salt concentration of 8% and soaking time of 1 d, which may be attributed to the variation in the solution salt and pore structure between the soil particles.
Author Contributions
Funding
Conflicts of Interest
References
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ρ | ρd | W | WL | Wp | Grain Size Fractions (%) | ||
---|---|---|---|---|---|---|---|
<0.005 mm | 0.005–0.05 mm | >0.05 mm | |||||
1.58 | 1.36 | 16 | 26.37 | 22.55 | 13.38 | 61.27 | 25.34 |
Soaking Time (d) | Peak Strength (kPa) | Residual Strength (kPa) | NaCl Concentration (%) | Peak Strength (kPa) | Residual Strength (kPa) |
---|---|---|---|---|---|
0 | 174.80 | 169.84 | 0 | 167.45 | 166.83 |
1 | 161.19 | 155.67 | 4 | 173.73 | 171.92 |
5 | 167.60 | 166.89 | 8 | 186.07 | 170.92 |
10 | 167.12 | 163.03 | 12 | 171.69 | 169.43 |
15 | 167.43 | 165.25 | 16 | 167.05 | 168.24 |
20 | 167.23 | 167.15 | 20 | 164.11 | 165.97 |
25 | 167.42 | 168.15 |
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Xue, C.; Wang, X.; Liu, K. Effect of Soaking Time and Salt Concentration on Mechanical Characteristics of Slip Zone Soil of Loess Landslides. Water 2020, 12, 3465. https://doi.org/10.3390/w12123465
Xue C, Wang X, Liu K. Effect of Soaking Time and Salt Concentration on Mechanical Characteristics of Slip Zone Soil of Loess Landslides. Water. 2020; 12(12):3465. https://doi.org/10.3390/w12123465
Chicago/Turabian StyleXue, Chen, Xingang Wang, and Kai Liu. 2020. "Effect of Soaking Time and Salt Concentration on Mechanical Characteristics of Slip Zone Soil of Loess Landslides" Water 12, no. 12: 3465. https://doi.org/10.3390/w12123465
APA StyleXue, C., Wang, X., & Liu, K. (2020). Effect of Soaking Time and Salt Concentration on Mechanical Characteristics of Slip Zone Soil of Loess Landslides. Water, 12(12), 3465. https://doi.org/10.3390/w12123465