Geopolymer was employed to stabilize loess, and the degradation behavior of its shear strength under sulfate erosion was investigated through triaxial tests, and scanning electron microscopy analysis was conducted to further understand the degradation mechanism of the stabilized loess. The results show that: The incorporation of geopolymer can effectively improve the salt erosion resistance of cured loess, and the higher the incorporation rate, the more significant the improvement of erosion resistance. With the increase of salt erosion time, the shear strength of geopolymer-stabilized loess shows a linear deterioration trend. After 60 days of salt corrosion, 15% and 20% stabilized soil still possess 70% and 77% of the peak partial stress of undisturbed specimens, showing good salt corrosion resistance. However, the degradation degree of 10% solidified soil is relatively high, with only 45.4% of the peak deviatoric stress of undisturbed samples. The peak deviatoric stress decreases significantly, and the solidified structure has been partially lost. At 60 days, the cohesion of 15% and 20% solidified soil can still retain more than 70% of their original values, but the 10% geopolymer solidified soil deteriorates significantly, with a decrease of about 50%. The effect of salt erosion on the internal friction angle is relatively small, which decreases by 22.7%, 13.3% and 8.6% respectively for 10%, 15% and 20% geopolymer stabilized loess. The scanning electron microscopy analysis shows that the structural deterioration of geopolymer solidified loess caused by sulfate solution is manifested in two aspects: In the short term, the pore water erosion is more significant;In the long-term immersion process, sulfate ion reacts with GP, resulting in the decomposition of hydration products, therefore the macro strength decreases.
Liu Fei
,
Zhang Xing
,
Yin Yan
,
Tang Haojie
,
Shi Wenke
. Study on the Strength Deterioration Mechanism of Geopolymer-Stabilized Loess under Salt Erosion[J]. Chinese Journal of Underground Space and Engineering, 2025
, 21(S2)
: 589
-595
.
DOI: 10.20174/j.JUSE.2025.S2.07
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