Frost heave and heaving pressure measurements in colliery shales

1976 ◽  
Vol 13 (2) ◽  
pp. 127-138 ◽  
Author(s):  
R. J. Kettle ◽  
R. I. T. Williams
Keyword(s):  
Pore Size ◽  
Side Wall ◽  
Frozen Soil ◽  
Soil Freezing ◽  
Frost Heave ◽  
Theoretical Studies ◽  
Pressure Measurements ◽  
Thermoelectric Devices ◽  
Cement Stabilization ◽  
Experimental Rig

The paper describes a technique for measuring the pressure generated when heaving is restrained in a frozen soil, freezing being achieved by thermoelectric cooling. Although steps were taken to minimize side wall resistance between the specimen and the test mould significant under-estimation of the pressure was unavoidable and further work is necessary to accurately quantify the resistance.The tests were performed on specimens of unbound and cement stabilized colliery shale, both unburnt and burnt shales being studied. For the unbound shales, the largest heaving pressures were developed by the finer grained shales, and this supports the theoretical studies that have shown heaving pressure to be inversely proportional to pore size. Cement stabilization did not significantly affect the heaving pressure developed by the coarser grained shales but, with the finer grained shales, it reduced the pressure developed.Heave and heaving pressure are not uniquely related and, although relationships have been established between these parameters separately for burnt and for unburnt shale, the technique does not at present constitute an alternative to the frost heave test.The testing programme has shown, however, that thermoelectric devices provide a reliable and efficient means for freezing specimens and an experimental rig is suggested for using them in frost heave testing.

scholarly journals Theoretical Studies of Ice Segregation in Soil

1966 ◽  
Vol 6 (44) ◽  
pp. 255-260 ◽  
Author(s):  
Kiyoshi Arakawa
Keyword(s):  
Thermal Conductivity ◽  
Heat Conduction ◽  
Mathematical Theory ◽  
Frozen Soil ◽  
Soil Freezing ◽  
Heat Of Fusion ◽  
Theoretical Studies ◽  
Latent Heat Of Fusion ◽  
Two Parameters ◽  
Ice Segregation

Abstract The mathematical theory of heat conduction is applied to the analysis of ice segregation processes in soil. A diffusion equation is first employed for the flow of soil moisture. Two new quantities, the rate of ice segregation,σ and the segregation efficiency, E, are introduced. The first is the rate of ice growth measured as mass per area per time. The latter is defined as E = σL/(K 1 ∂T 1/∂x−K 2 ∂T 2/∂x), where L is the latent heat of fusion of ice, T 1and K 1are the temperature and thermal conductivity of frozen soil, and T 2 and K 2 are the temperature and thermal conductivity of unfrozen soil. Three types of soil freezing can be classified in terms of E: freezing of non-frost-susceptible soil (E = 0), perfect segregation (E = 1) and imperfect segregation (0 < E < 1). Finally, the mathematical boundary conditions at an advancing frost line are obtained in freezing, frost-susceptible soil (E ≠ 0). Two parameters related to the structure of soil are pointed out, which seem to be valid criteria of frost susceptibility. The amount of frost-heaving is derived under special conditions.

scholarly journals A Fractal Model of Hydraulic Conductivity for Saturated Frozen Soil

Water ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 369 ◽  
Author(s):  
Lei Chen ◽  
Dongqing Li ◽  
Feng Ming ◽  
Xiangyang Shi ◽  
Xin Chen
Keyword(s):  
Hydraulic Conductivity ◽  
Pore Structure ◽  
Pore Size Distribution ◽  
Pore Size ◽  
Size Distribution ◽  
Fractal Theory ◽  
Frozen Soil ◽  
Soil Freezing ◽  
Size Dimension ◽  
Maximum Pore Size

In cold regions, hydraulic conductivity is a critical parameter for determining the water flow in frozen soil. Previous studies have shown that hydraulic conductivity hinges on the pore structure, which is often depicted as the pore size and porosity. However, these two parameters do not sufficiently represent the pore structure. To enhance the characterization ability of the pore structure, this study introduced fractal theory to investigate the influence of pore structure on hydraulic conductivity. In this study, the pores were conceptualized as a bundle of tortuous capillaries with different radii and the cumulative pore size distribution of the capillaries was considered to satisfy the fractal law. Using the Hagen-Poiseuille equation, a fractal capillary bundle model of hydraulic conductivity for saturated frozen soil was developed. The model validity was evaluated using experimental data and by comparison with previous models. The results showed that the model performed well for frozen soil. The model showed that hydraulic conductivity was related to the maximum pore size, pore size dimension, porosity and tortuosity. Of all these parameters, pore size played a key role in affecting hydraulic conductivity. The pore size dimension was found to decrease linearly with temperature, the maximum pore size decreased with temperature and the tortuosity increased with temperature. The model could be used to predict the hydraulic conductivity of frozen soil, revealing the mechanism of change in hydraulic conductivity with temperature. In addition, the pore size distribution was approximately estimated using the soil freezing curve, making this method could be an alternative to the mercury intrusion test, which has difficult maneuverability and high costs. Darcy’s law is valid in saturated frozen silt, clayed silt and clay, but may not be valid in saturated frozen sand and unsaturated frozen soil.

Observations of soil freezing and frost heave at Inuvik, Northwest Territories, Canada

1985 ◽  
Vol 22 (2) ◽  
pp. 283-290 ◽  
Author(s):  
M. W. Smith
Keyword(s):  
Northwest Territories ◽  
Field Data ◽  
Negative Temperature ◽  
Frozen Soil ◽  
Soil Freezing ◽  
Frost Heave ◽  
Moisture Regime ◽  
Silty Clay ◽  
Field Observations ◽  
Moisture Migration

Field observations of soil temperature, moisture regime, and frost heave in silty clay hummocks at Inuvik, Northwest Territories, over the fall and early winter reveal that a significant amount of moisture migration and frost heave occurs within frozen soil at temperatures down to −2.4°C. The field data are analysed using thermodynamic considerations, and the apparent hydraulic conductivity is determined as a function of negative temperature. The conductivity falls from near 7 × 10−9 m s−1 above 0 °C to about 3.5 × 10−12 m s−1 at −1 °C, then remains fairly constant down to −2.4 °C. The observed decrease in heave with time is explained in terms of a diminishing water supply at the base of the active layer.

Modeling soil freeze-thaw and ice effect on canal bank

1998 ◽  
Vol 35 (4) ◽  
pp. 655-665 ◽  
Author(s):  
Z X Zhang ◽  
R L Kushwaha
Keyword(s):  
Frozen Soil ◽  
Soil Freezing ◽  
Frost Heave ◽  
Energy Status ◽  
Abrupt Increase ◽  
Water Ice ◽  
Freeze Thaw ◽  
Thaw Cycle ◽  
Initial Soil ◽  
Freeze Thaw Cycle

The experiments for modeling soil freeze-thaw and ice action on canal banks were conducted in a laboratory. In addition to the frost heave that was observed during the period of soil freezing, there was an abrupt increase in frost heave that occurred at the beginning of soil thawing. This phenomenon lasted for over approximately 100 hours, and the frost heave induced during this period reached as much as 22.62 mm. At the same time, peak ice pressures also occurred as the soil was thawing. It has been suggested that the frost heave during initial soil thawing may be associated with the change in energy status at the water-ice interface resulting from the buildup of internal stress in the soil during the formation of ice lenses.Key words: frozen soil, freeze-thaw cycle, frost heave, thawing settlement, canal protection.

Theoretical Studies of Ice Segregation in Soil

1966 ◽  
Vol 6 (44) ◽  
pp. 255-260
Author(s):  
Kiyoshi Arakawa
Keyword(s):  
Thermal Conductivity ◽  
Heat Conduction ◽  
Mathematical Theory ◽  
Frozen Soil ◽  
Soil Freezing ◽  
Heat Of Fusion ◽  
Theoretical Studies ◽  
Latent Heat Of Fusion ◽  
Two Parameters ◽  
Ice Segregation

AbstractThe mathematical theory of heat conduction is applied to the analysis of ice segregation processes in soil. A diffusion equation is first employed for the flow of soil moisture. Two new quantities, the rate of ice segregation,σ and the segregation efficiency, E, are introduced. The first is the rate of ice growth measured as mass per area per time. The latter is defined as E = σL/(K1∂T1/∂x−K2∂T2/∂x), where L is the latent heat of fusion of ice, T1and K1are the temperature and thermal conductivity of frozen soil, and T2 and K2 are the temperature and thermal conductivity of unfrozen soil. Three types of soil freezing can be classified in terms of E: freezing of non-frost-susceptible soil (E = 0), perfect segregation (E = 1) and imperfect segregation (0 < E < 1). Finally, the mathematical boundary conditions at an advancing frost line are obtained in freezing, frost-susceptible soil (E ≠ 0). Two parameters related to the structure of soil are pointed out, which seem to be valid criteria of frost susceptibility. The amount of frost-heaving is derived under special conditions.

Discrete ice lens theory for frost heave in soils

1991 ◽  
Vol 28 (6) ◽  
pp. 843-859 ◽  
Author(s):  
J. F. (Derick) Nixon
Keyword(s):  
Hydraulic Conductivity ◽  
Temperature Gradient ◽  
Frozen Soil ◽  
Soil Freezing ◽  
Frost Heave ◽  
Overburden Pressure ◽  
Discrete Location ◽  
Freezing Soil ◽  
Analytical Technique ◽  
Segregation Potential

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.

Stress Analysis of Pipeline Subjected to Differential Frost Heave

2013 ◽  
Author(s):  
Yan Di ◽  
Jian Shuai ◽  
Lingzhen Kong ◽  
Xiayi Zhou
Keyword(s):  
Strain Analysis ◽  
Element Model ◽  
Frozen Soil ◽  
Computational Method ◽  
Frost Heave ◽  
Safe Operation ◽  
Stress Strain ◽  
Segregation Potential ◽  
Differential Frost Heave ◽  
Design Construction

Frost heave must be considered in cases where pipelines are laid in permafrost in order to protect the pipelines from overstress and to maintain the safe operation. In this paper, a finite element model for stress/strain analysis in a pipeline subjected to differential frost heave was presented, in which the amount of frost heave is calculated using a segregation potential model and considering creep effects of the frozen soil. In addition, a computational method for the temperature field around a pipeline was proposed so that the frozen depth and temperature variation gradient could be obtained. Using the procedure proposed in this paper, stress/strain can be calculated according to the temperature on the surface of soil and in a pipeline. The result shows the characteristics of deformation and loading of a pipeline subjected to differential frost heave. In general, the methods and results in this paper can provide a reference for the design, construction and operation of pipelines in permafrost areas.

Microstructure-Based Random Finite Element Method Simulation of Frost Heave: Theory and Implementation

2018 ◽  
Vol 2672 (52) ◽  
pp. 347-357 ◽  
Author(s):  
Shaoyang Dong ◽  
Xiong (Bill) Yu
Keyword(s):  
Finite Element ◽  
Ground Surface ◽  
Finite Element Method Simulation ◽  
Element Model ◽  
Frozen Soil ◽  
Traffic Load ◽  
Frost Heave ◽  
Holistic Model ◽  
Water Pipes ◽  
Random Finite Element

Frost heave can cause serious damage to civil infrastructure. For example, interactions of soil and water pipes under frozen conditions have been found to significantly accelerate pipe fracture. Frost heave may cause the retaining walls along highways to crack and even fail in cold climates. This paper describes a holistic model to simulate the temperature, stress, and deformation in frozen soil and implement a model to simulate frost heave and stress on water pipelines. The frozen soil behaviors are based on a microstructure-based random finite element model, which holistically describes the mechanical behaviors of soils subjected to freezing conditions. The new model is able to simulate bulk behaviors by considering the microstructure of soils. The soil is phase coded and therefore the simulation model only needs the corresponding parameters of individual phases. This significantly simplifies obtaining the necessary parameters for the model. The capability of the model in simulating the temperature distribution and volume change are first validated with laboratory scale experiments. Coupled thermal-mechanical processes are introduced to describe the soil responses subjected to sub-zero temperature on the ground surface. This subsequently changes the interaction modes between ground and water pipes and leads to increase of stresses on the water pipes. The effects of cracks along a water pipe further cause stress concentration, which jeopardizes the pipe’s performance and leads to failure. The combined effects of freezing ground and traffic load are further evaluated with the model.

scholarly journals Field Frost Heave Prediction Related to Ice Segregation Processes During Soil Freezing

1985 ◽  
Vol 6 ◽  
pp. 87-91 ◽  
Author(s):  
Masami Fukuda ◽  
Seiiti Kinosita
Keyword(s):  
Soil Freezing ◽  
Frost Heave ◽  
Heave Prediction ◽  
Ice Segregation

Experimental study on laws of frost heave and thawing settlement of the artificially frozen soil

2004 ◽  
pp. 493-496
Author(s):  
Wenshun Wang ◽  
Jianping Wang ◽  
Huiguang Yin
Keyword(s):  
Experimental Study ◽  
Frozen Soil ◽  
Frost Heave
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