Abstract
Previous studies have shown that an accurate prediction of frost heaves largely depends on the pore water pressure and hydraulic conductivity of frozen fringes, which are difficult to determine. The segregation potential model can avoid this problem; however, the conventional segregation potential is considered to be approximately unchanged at a steady state and only valid in an open system without dehydration in the unfrozen zone. Based on Darcy’s law and the conventional segregation potential, the segregation potential was expressed as a function of the pore water pressure at the base of the ice lens, the pore water pressure at the freezing front, the freezing temperature, the segregation freezing temperature and the hydraulic conductivity of the frozen fringe. This expression indicates that the segregation potential under quasi-steady-state conditions is not a constant in a closed system, since the pore water pressure at the freezing front varies with the freezing time owing to the dehydration of the unfrozen zone, and that when the pore water pressure at the freezing front is equal to that at the base of the ice lens, the water migration and frost heave will be terminated. To analyze the possibility of applying the segregation potential model in a closed system, a series of one-sided frost heave tests under external pressure in a closed system were carried out in a laboratory, and the existing frost heaving test data from the literature were also analyzed. The results indicate that the calculated frost heave was close to the tested data, which shows the applicability of the model in a closed system. In addition, the results show the rationality of calculating the segregation potential from the frost heaving test by comparing the potential with that calculated from the numerical simulation results. This study attempted to extend the segregation potential model to freezing soil in a closed system and is significant to the study of frost heaves.
Highlights
Infrastructure built in cold regions, such as roads [1], railways [2], pipelines [3], buildings [4] and dams [5], is always subject to frost heaves, resulting in great damage
The frost heave displacement under no load increased with the freezing time, while the frost heave displacement under the external pressures decreased with the freezing time, while the frost heave displacement under the external pressures decreased first and increased with the freezing time because the soil samples were compressed under the first and increased with the freezing time because the soil samples were compressed under the external pressures during the frost heaving process
The frost heave displacement with increasing external pressure, and compression instead of swelling was found when the pressure decreased with increasing external pressure, and compression instead of swelling was found when increased to 153 kPa because the amount of frost heave displacement was less than the amount of the pressure increased to 153 kPa because the amount of frost heave displacement was less than the compression
Summary
Infrastructure built in cold regions, such as roads [1], railways [2], pipelines [3], buildings [4] and dams [5], is always subject to frost heaves, resulting in great damage. The theory suggested that the difference in pore water pressure of frozen fringes was the main driving force for water migration Based on this second frost heave theory, the rigid ice model was first proposed by O’Neill and Miller [7]. Lengthy simulations would be required when applying the abovementioned frost heave models, which could require a week or more To address this problem, Konrad and Morgenstern [15] proposed the segregation potential model, which suggests that the water migration rate is proportional to the temperature gradient at the formation of the final ice lens, and this proportion is the so-called segregation potential, v0 = SP0 gradT, where SP0 is a constant. The possibility of the application of the model in a closed system was illustrated by a series of frost heave tests and the simulation method
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
