Study on the stability of highway slope in cold region under freeze-thaw cycles

Hongyu Chen,Xizhong Yuan,Wenbo Liu,L Wang,V Yepes

doi:10.1051/e3sconf/202124803046

Abstract

Based on thermo-mechanical coupling and elastoplastic theory, a finite element (FE) numerical simulation was adopted to study the stability of slopes in cold regions under freeze-thaw cycles. And the prediction of slope landslide was also studied through the calculation of strength reduction coefficients combination. The result shows that the development of the slope vertical displacement under freeze-thaw cycles can be divided into two stages: rapid stage and stable stage. After combining the two reduction coefficients of cohesion and internal friction of the soil, the maximum vertical displacement on the top of the slope in this region can be calculated as a reference for predicting the slope landslides. Meanwhile, the corresponding safety factor of the slope in the cold region can be obtained according to the reduction coefficients. .

Highlights

With the global warming, the instability and landslides of slopes in cold regions are gradually increasing [1]
The soil slopes in cold regions are subjected to the effects of repeated thawing settlement and frost heave under the temperature cycle, so that the strength of the slope soil is reduced and leads to instability [6,7]
Slope landslide is affected by many factors, such as the moisture content of the soil, the shear strength and the cohesion of the soil, the grade of the slope, etc

Summary

Introduction

The instability and landslides of slopes in cold regions are gradually increasing [1]. The research on the stability of frozen soil slopes in cold regions has become more and more important. The positive freezing landslides, positive thawing landslides, and freezing-thaw landslides are the main types of instability to slopes in cold regions, and thermal thawing is a common cause of slope landslides in cold regions [2,3]. The soil slopes in cold regions are subjected to the effects of repeated thawing settlement and frost heave under the temperature cycle, so that the strength of the slope soil is reduced and leads to instability [6,7]. Freeze-thaw in the temperature cycle only occurs in the soil in the seasonal active layer, for which the traditional slope stability analysis method is not suitable. The displacement field of the slope under freeze-thaw cycles was analysed, and its sliding process was discussed

Theory

Geometric model and parameters

Boundary conditions

Slope stability

Slope stability prediction

Conclusion