A Coupled Thermo‐Hydromechanical Model of Soil Slope in Seasonally Frozen Regions under Freeze‐Thaw Action

Abstract

Soil slope diseases in seasonally frozen regions are mostly related to water migration and frost heave deformation of the soil. Based on the partial differential equation defined using the COMSOL Multiphysics software, a thermo-hydromechanical coupling model considering water migration, ice-water phase change, ice impedance, and frost heave is constructed, and the variations in the temperature field, migration of liquid water, accumulation of solid ice, and deformation of frost heave in frozen soil slopes are analysed. e results show that the ambient temperature has a significant effect on the temperature and moisture field of the slope in the shallow area. In addition, the degree of influence gradually weakens from the outside to the inside of the slope, and the number of freeze-thaw cycles in deep soil is less than that in shallow soil. During the freezing period, water in the unfrozen area rapidly migrates to the frozen area, and the total moisture content abruptly changes at the vicinity of the freezing front. e maximum frozen depth is the largest at the slope top and the smallest at the slope foot. During the melting period, water is enriched at the melting front with the frozen layer melting; the slope is prone to shallow instability at this stage. e melting of the frozen layer is bidirectional, so the duration of slope melting is shorter than that of the freezing process. e slope displacement is closely related to the change in temperature-a relation that is in agreement with the phenomenon of thermal expansion and contraction in unfrozen areas and reflects the phenomenon of frost heave and thaw settlement in frozen areas.

Frost Resistance and Shrinkage Characteristics of Soil Stabilized by Carbide Slag and Coal Gangue Powder

“…China is a vast country with a large north-south span and large climatic differences, among which seasonal frozen soil reaches 53.5% [1]. With the development of the western region and the proposal of the "Belt and Road" initiative, a large number of infrastructures have been built in regions with seasonal frozen soil, and more than 2/3 of roads in China cross regions with seasonal frozen soil [2,3].…”

A Freezing-Thawing Damage Characterization Method for Highway Subgrade in Seasonally Frozen Regions Based on Thermal-Hydraulic-Mechanical Coupling Model

“…It can be di-vided into permafrost and seasonally frozen soil if a seasonal freezing period exists. Seasonally frozen areas are widely distributed, accounting for 53% of the world’s land area, while in China, they account for 53.5% of the total land area [ 1 , 2 , 3 ]. China’s Belt and Road Initiative increased infrastructure construction in the Qinghai-Tibet seasonally frozen regions where multiple highway projects are planned [ 4 , 5 ].…”

Study on Varying Characteristics of Temperature Field and Moisture Field of Shallow Loess in the Freeze‐Thaw Period

“…Ye et al [12], according to the field investigation and experimental study, maintained that the deterioration of loess strength, caused by the moisture transfer under the freeze-thaw effect, plays a vital part in the slope and spalling of loess. Drawing on the numerical simulation analysis, Zhan et al [13] proposed the close correlation of slope disease in the seasonal frozen ground region with moisture variation. In this regard, it is of great necessity to study the law of temperature and moisture variation of shallow soil and further reveal the occurrence mechanism of engineering diseases.…”