Water flow induced by soil freezing

1977 ◽  
Vol 14 (2) ◽  
pp. 237-245 ◽  
Author(s):  
Wayne D. Arvidson ◽  
Norbert R. Morgenstern

A study to observe the effects of overburden pressure and other parameters on the freezing behavior of a saturated soil was undertaken. A linear relationship between effective overburden pressure and the flow of water into or out of a freezing soil was observed. The effective pressure at which no flow occurred was termed the shutoff pressure. At pressures less than the shutoff pressure water was sucked to the freezing front resulting in segregated ice, ice lensing, and heaving. This heaving could significantly exceed the heave due to the volumetric expansion of the in situ porewater. At pressures greater than the shutoff pressure water was expelled from the freezing front thereby reducing the volume of in situ water and resulting in a relatively small amount of heave. Shutoff pressure was observed to depend on soil type, stress history, and freezing temperature. The effects of overburden pressure upon flow of water in a freezing soil and frost heave were recommended as additional criteria for assessing soil frost susceptibility.


Water ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2418
Author(s):  
Xiyan Zhang ◽  
Yu Sheng ◽  
Long Huang ◽  
Xubin Huang ◽  
Binbin He

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.



1991 ◽  
Vol 28 (6) ◽  
pp. 843-859 ◽  
Author(s):  
J. F. (Derick) Nixon

The existing segregation potential (SP) method for frost heave prediction in soils is semiempirical in nature and does not explicitly predict the relationship between heave rate, temperature gradient, and other more fundamental soil properties. The SP method assumes that the heave rate is directly related to the temperature gradient at the frost front but acknowledges that the SP parameter is dependent on pressure, suction at the frost front, cooling rate, soil type, and so forth. This paper extends and modifies an approximate analytical technique of Gilpin and accounts for the effects of distributed phase change within the freezing fringe in both the head- and mass-transfer components of the formulation. The approach requires as input a relationship between frozen hydraulic conductivity and temperature and predicts the discrete location of each ice lens within the freezing soil. The solution can be carried out quickly on a microcomputer to obtain the heave, suction at the frost front, ice lens temperature, and other results of interest with time. Furthermore, the discrete ice lens method predicts the effects of changing overburden pressure on the predicted heave rate. A method of extracting input parameters for the discrete ice lens procedure from a series of frost heave tests is proposed. The discrete ice theory has been tested and calibrated against well-documented frost heave test results in the literature, and very encouraging agreement between prediction and observation has been obtained. Key words: frost heave, discrete ice lens, segregation potential, hydraulic conductivity of frozen soil, freezing soil.



1981 ◽  
Vol 18 (4) ◽  
pp. 583-585 ◽  
Author(s):  
Edward Penner

Results are presented over a wide range of soil textures supporting the linear relation between the logarithm of frost heave rate and the cold-side temperature – overburden pressure ratio proposed by Penner and Ueda. The relation is simple to determine experimentally, permits heave predictions at various other temperature and pressure conditions for engineering purposes, and allows soil frost susceptibility comparisons to be made with the results determined by other laboratories.



2020 ◽  
Vol 10 (21) ◽  
pp. 7753
Author(s):  
Lin Geng ◽  
Shengyi Cong ◽  
Jun Luo ◽  
Xianzhang Ling ◽  
Xiuli Du ◽  
...  

In analyzing frost heave, researchers often simplify the compressive modulus of freezing soil by considering it as a constant or only as a function of temperature. However, it is a critical parameter characterizing the stress–strain behavior of soil and a variable that is influenced by many other parameters. Hence, herein several one-dimensional freezing experiments are conducted on silty clay in an open system subjected to multistage freezing by considering the compressive modulus as a variable. First, freezing soil under multistage freezing is divided into several layers according to the frozen fringe theory. Then, the correlation between the freezing rate and temperature gradient within each freezing soil layer is investigated. Takashi’s equation for frost heave analysis is modified to extend its application conditions by replacing its freezing rate term with a temperature gradient term. A mechanical model for the stress–strain behavior of freezing soil under the action of frost heave is derived within the theoretical framework of nonlinear elasticity, in which a method for determining the compressive modulus of freezing soil with temperature gradient, overburden pressure, and cooling temperature variables is proposed. This study further enhances our understanding of the typical mechanical behavior of saturated freezing silty clay under frost heave action.



1982 ◽  
Vol 19 (4) ◽  
pp. 494-505 ◽  
Author(s):  
J.-M. Konrad ◽  
N. R. Morgenstern

Background studies illustrating the effect of externally applied pressure on frost heave are reviewed together with some of the thermodynamic aspects of pressure effects. New experimental data are presented to show how the segregation potential varies with applied pressure. This variation is explained in terms of the influence of applied pressure on the segregation-freezing temperature and the average permeability of the frozen fringe. An explanation is given of the change in mode from expulsion to attraction of water to the freezing front in a loaded soil and it is shown that segregation can be eliminated by externally applied loads. However, these loads are generally too high to be of engineering interest. While it has been concluded that, under laboratory freezing conditions, the segregation potential is dependent upon applied pressure, suction at the frost front, and rate of cooling of the frozen fringe, field conditions are often simpler. A simplified method of predicting frost heave under field conditions is developed that should lead to conservative results.



2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Feng Ming ◽  
Dong-qing Li

For the construction in cold regions, frost heave and thaw settlement are the two factors which must be taken care of. Considered that a saturated soil column was subjected to an overburden pressure to model the ice lens growing process. A typical process, which coupled water, heat, and stress that happened in a saturated freezing soil column, was simulated by the finite element software. We did the numerical simulation under the same conditions as the experiment tests and then compared the results from temperature, frost heave, frozen structure, water content, and water intake. Result shows that the simulation results match well with the experimental results, and the correctness of the mathematical model is validated. On that basis, frost heave amount under different conditions by changing the temperature boundary and loading boundary is obtained. The frost heave has an optimum temperature gradient. Under the optimum value, the frost heave amount increases with increasing temperature gradient. Above the optimum value, frost heave decreases with increasing temperature gradient. Increasing the overburden pressure, frost heave amount always decreases. These results can provide references for the constrictions in cold regions.



2014 ◽  
Vol 912-914 ◽  
pp. 136-140 ◽  
Author(s):  
Hui Xin Zhao ◽  
Jing Zhong ◽  
Zheng Jun Wang

Freezing temperature is one of the main factors of soil frost heave, and different cooling modes will also have an effect on frost heave. To study the influence of stepwise cooling mode to frost heave of silty clay, this paper did the tests of frost heave on the silty clay in stepwise cooling mode and continuous cooling mode respectively, which got versus time of temperature gradient field and frost heave amount in the phenomena of frost heave and frost shrinkage by the two cooling modes. It turns out that stepwise cooling mode will produce greater frost heave and larger frost heave rate, and when frost shrinkage phenomenon occurs, the amount of frost shrinkage is bigger also. Its mechanism lies in the cooling rate with stepwise cooling mode is smaller than that with continuous cooling mode, and it can promote the water migration.



2013 ◽  
Vol 734-737 ◽  
pp. 2659-2663
Author(s):  
Yun Bin Ma ◽  
Dong Jie Tan ◽  
Hong Yuan Jing ◽  
Quan Xue ◽  
Cheng Zhi Zhang

The crude oil pipeline from MoHe to DaQing (hereafter called Mo-Da pipeline) is part of China-Russia oil pipeline. Mo-Da pipeline is the first pipeline that through high latitude cold regions of China. The pipeline is in so complicated geography environment that many kinds of permafrost hazard are easily to happen including frost heave, thaw settlement, slope instabilities, and collapse and so on. The pipeline and the permafrost act and react upon one another. On one hand, soil frost heave and thaw settlement can produce extra stresses on pipe walls, which may result in centralized stresses and plastic deformations under certain conditions, even causes pipeline faults. On the other hand, buried pipeline will disturb ambient environment and then degrade the permafrost soil and finally impact safety of the pipeline. This paper mainly introduces the permafrost hazards of Mo-Da pipeline and demonstrates some methods for monitoring the influence of permafrost.



Author(s):  
Виктор Григорьевич Чеверев ◽  
Евгений Викторович Сафронов ◽  
Алексей Александрович Коротков ◽  
Александр Сергеевич Чернятин

Существуют два основных подхода решения задачи тепломассопереноса при численном моделировании промерзания грунтов: 1) решение методом конечных разностей с учетом граничных условий (границей, например, является фронт промерзания); 2) решение методом конечных элементов без учета границ модели. Оба подхода имеют существенные недостатки, что оставляет проблему решения задачи для численной модели промерзания грунтов острой и актуальной. В данной работе представлена физическая постановка промерзания, которая позволяет создать численную модель, базирующуюся на решении методом конечных элементов, но при этом отражающую ход фронта промерзания - то есть модель, в которой объединены оба подхода к решению задачи промерзания грунтов. Для подтверждения корректности модели был проделан ряд экспериментов по физическому моделированию промерзания модельного грунта и выполнен сравнительный анализ полученных экспериментальных данных и результатов расчетов на базе представленной численной модели с такими же граничными условиями, как в экспериментах. There are two basic approaches to solving the problem of heat and mass transfer in the numerical modeling of soil freezing: 1) using the finite difference method taking into account boundary conditions (the boundary, for example, is the freezing front); 2) using the finite element method without consideration of model boundaries. Both approaches have significant drawbacks, which leaves the issue of solving the problem for the numerical model of soil freezing acute and up-to-date. This article provides the physical setting of freezing that allows us to create a numerical model based on the solution by the finite element method, but at the same time reflecting the route of the freezing front, i.e. the model that combines both approaches to solving the problem of soil freezing. In order to confirm the correctness of the model, a number of experiments on physical modeling of model soil freezing have been performed, and a comparative analysis of the experimental data obtained and the calculation results based on the provided numerical model with the same boundary conditions as in the experiments was performed.



1985 ◽  
Vol 6 ◽  
pp. 87-91 ◽  
Author(s):  
Masami Fukuda ◽  
Seiiti Kinosita


Sign in / Sign up

Export Citation Format

Share Document