FAN Jinke1, 2, YUE Zurun1, HAN Zihao1, 2, SUN Tiecheng1, HU Tianfei1, ZHANG Song1
Journal of Glaciology and Geocryology.
Online available: 2024-04-28
To explore the influence of freeze-thaw cycles on the strength of moraine soil, this study established a prediction model of the strength deterioration of moraine soil under different numbers of freeze-thaw cycles. Using moraine soil in the western extreme cold and high-altitude area as the research object, the influence of numbers of freeze-thaw cycles and initial water content on the failure strength of moraine soil was explored by carrying out indoor freeze-thaw cycle tests and unconsolidated undrained triaxial tests, and the corresponding prediction model was established. The experimental results show that freeze-thaw cycles have a great influence on the strength of moraine soil. Under different testing conditions, the strength of moraine soil degrades in the range from 30% to 40%, and the strength tends to keep stable after 15 to 20 freeze-thaw cycles. Based on the SSA-BP neural network model, the complex nonlinear relationship between the failure strength of moraine soil and the number of freeze-thaw cycles, initial water content and confining pressure can be reflected. The prediction error is significantly smaller than that of the BP neural network model, and the prediction results are more accurate. Comparing the SSA-BP neural network model with the Logistic model used in linear fitting, it is found that two results have a high degree of agreement, which further illustrates the accuracy of the SSA-BP model. This research can provide important parameters for engineering stability evaluation in western cold and high-altitude areas.