Sixteenth Canadian Geotechnical Colloquium: Frost heave in soils: concepts and engineering

1994 ◽  
Vol 31 (2) ◽  
pp. 223-245 ◽  
Author(s):  
J.-M. Konrad
Keyword(s):  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Point Of View ◽  
Frost Heave ◽  
Fundamental Point ◽  
New Concepts ◽  
Segregation Potential ◽  
Thermal Histories ◽  
Ice Content ◽  
Lens Formation

Frost heave in soils is analysed from a fundamental point of view to predict the development of periodic ice lens formation that is observed in frozen soils. A model of simultaneous heat and mass transfer associated with three new concepts is described and was found to exhibit many of the frost heave features observed in laboratory tests. An efficient frost heave parameter termed the segregation potential, SP, is also described and found to be an adequate input to a general formulation of heat and mass transfer for the prediction of frost heave in soils for both laboratory and field conditions. Representative values of SP depend on the stress and thermal histories of the soil deposit. The SP-based approach can be used for solving two-dimensional frost heave problems and yields stress, temperature, and ice-content distributions with time. Key words : frost heave, soils, segregation potential, simulation, thermodynamics.

scholarly journals Frost Heave due to Ice Lens Formation in Freezing Soils

1995 ◽  
Vol 26 (2) ◽  
pp. 147-168 ◽  
Author(s):  
D. Sheng ◽  
K. Axelsson ◽  
S. Knutsson
Keyword(s):  
Mass Transfer ◽  
Heat Flow ◽  
Field Measurements ◽  
Frost Heave ◽  
Research Model ◽  
Governing Equations ◽  
Operational Model ◽  
Soil Layers ◽  
Time Period ◽  
Lens Formation

An operational model for estimation of frost heave in field where stratified soil profile appears is presented. The model is developed from the research model described in part B. Soil layers are first classified into frost-susceptible layers (FSL) or non-frost-susceptible layers (NFSL). In an FSL, both heat flow and water flow are considered and ice lensing can occur. In a NFSL, only heat flow is possible and no ice lensing is allowed. The governing equations for heat and mass transfer are established for the time period when the frost front is moving within FSL. Capillarity and unsaturation are also considered. The operational model is verified by field measurements of heave amounts. Examples of application are given.

Influence of overconsolidation on the freezing characteristics of a clayey silt

1989 ◽  
Vol 26 (1) ◽  
pp. 9-21 ◽  
Author(s):  
J.-M. Konrad
Keyword(s):  
Hydraulic Conductivity ◽  
Void Ratio ◽  
Moisture Transfer ◽  
Frozen Soil ◽  
Frost Heave ◽  
Unfrozen Water ◽  
Initial Void Ratio ◽  
Clayey Silt ◽  
Segregation Potential ◽  
Lens Formation

Laboratory freezing tests were performed on a saturated clayey silt at various overconsolidation ratios (OCR) to establish the relationship between initial void ratio and stress history, and the amount of moisture transfer during freezing. The frost heave tests were analysed in terms of the segregation potential as well as a function of the temperature of ice lens formation and the overall hydraulic conductivity of the frozen fringe. All other factors being the same, the segregation potential was found to increase with increasing values of OCR (decreasing initial void ratios). However, the combined effects of decreasing void ratio and increasing suction at the frost line, all other factors being identical in all freezing tests, resulted in decreasing segregation potentials. This trend was the result of a decrease in the temperature of ice lens formation and the concomitant decrease in overall hydraulic conductivity of the frozen fringe. A simple model showed that the capillary unfrozen water between clay particles increases when the particles pack closer together, as overconsolidation increases, allowing the migratory water to freeze within the frozen soil at a colder temperature. Key words: frost heave, clayey silt, overconsolidation, void ratio.

scholarly journals Frost heave prediction of chilled pipelines buried in unfrozen soils

1984 ◽  
Vol 21 (1) ◽  
pp. 100-115 ◽  
Author(s):  
J.-M. Konrad ◽  
N. R. Morgenstern
Keyword(s):  
Mass Transfer ◽  
Test Site ◽  
Frost Heave ◽  
Saturated Soils ◽  
Buried Pipelines ◽  
Finite Difference Formulation ◽  
Segregation Potential ◽  
Pipe Insulation ◽  
Good Agreement

Frost heave is an important consideration in the design of buried chilled pipelines. A procedure for calculating the amount of heave under a chilled gas pipeline is presented based on a finite-difference formulation of the heat and mass transfer in saturated soils. The frost heave of the soil is characterized in terms of the segregation potential concept developed in earlier papers by the authors. Good agreement is found between the predictions of heave obtained with this procedure and that observed in long-term full-scale experiments at a test site in Calgary, Canada. Additional calculations are presented to explore the influence of pipeline temperature, pipe insulation, and ground temperature on frost heave of buried pipelines.

Prediction of frost heave in the laboratory during transient freezing

1982 ◽  
Vol 19 (3) ◽  
pp. 250-259 ◽  
Author(s):  
J.-M. Konrad ◽  
N. R. Morgenstern
Keyword(s):  
Mass Transfer ◽  
Steady State ◽  
Temperature Gradient ◽  
Water Intake ◽  
Applied Load ◽  
Frost Heave ◽  
Freezing Soil ◽  
Fine Grained ◽  
Segregation Potential ◽  
Rate Of Cooling

Previous studies have demonstrated that, close to steady-state conditions, the ratio of the water intake velocity to the temperature gradient across the frozen fringe, called the segregation potential, is an important property characterizing a freezing soil. Under the more general conditions of transient freezing it is shown that the freezing characteristics of a given soil under zero applied load are defined by the segregation potential, the suction at the frozen–unfrozen interface, and the rate of cooling of the frozen fringe. These parameters form a relationship called the characteristic frost heave surface that can be used to predict mass transfer during the freezing of fine-grained soils. Examples of freezing tests conducted under various conditions are reproduced numerically to illustrate the fundamental character of this surface.

scholarly journals Fundamental approaches in mathematical modeling of drying processes of capillary-porous and dispersed materials

2017 ◽  
pp. 27-50
Author(s):  
Bogdana Hayvas
Keyword(s):  
Mathematical Modeling ◽  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Continuous Medium ◽  
Mechanical Characteristics ◽  
Fractal Structure ◽  
Point Of View ◽  
Theory Of Mixtures ◽  
Statistical Approaches ◽  
The Many

A review of main approaches to the mathematical modeling of heat and mass transfer in the process of drying of capillary-porous and disperse materials is presented. The peculiarities of the models construction from the point of view of the mechanics of a continuous medium, the theory of mixtures, statistical approaches and with taking into account the fractal structure are considered, which allows one to expand the many implementations of models, to take into account the anisotropy of thermo-mechanical characteristics, elastic and visco-elastic properties, etc.

THE SLIP AND INDUCED MAGNETIC FIELD EFFECTS ON THE PERISTALTIC TRANSPORT WITH HEAT AND MASS TRANSFER

2012 ◽  
Vol 12 (04) ◽  
pp. 1250068 ◽  
Author(s):  
T. HAYAT ◽  
S. NOREEN ◽  
A. ALSAEDI
Keyword(s):  
Magnetic Field ◽  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Point Of View ◽  
Slip Condition ◽  
Magnetic Field Effects ◽  
Asymmetric Channel ◽  
Induced Magnetic Field ◽  
Physical Point ◽  
Quantities Of Interest

In this attempt, simultaneous effects of slip condition and an induced magnetic field on the peristaltic flow of viscous fluid in an asymmetric channel is investigated. The whole analysis have been carried out in the presence of heat and mass transfer characteristics. The resulting mathematical model is solved by exploiting the boundary conditions derived from physical point of view. The expressions of the desired flow quantities of interest are derived and discussed. A comparison with no-slip condition is shown.

Radiation Damage in Ceramics

1982 ◽  
Vol 40 ◽  
pp. 600-603
Author(s):  
T. E. Mitchell ◽  
M. R. Pascucci ◽  
R. A. Youngman
Keyword(s):  
Radiation Damage ◽  
Outer Space ◽  
Point Of View ◽  
Nuclear Waste Storage ◽  
Waste Storage ◽  
Storage Media ◽  
Transmission Electron ◽  
Fundamental Point ◽  
Small Defect ◽  
Present Understanding

1. Introduction. Studies of radiation damage in ceramics are of interest not only from a fundamental point of view but also because it is important to understand the behavior of ceramics in various practical radiation enyironments- fission and fusion reactors, nuclear waste storage media, ion-implantation devices, outer space, etc. A great deal of work has been done on the spectroscopy of point defects and small defect clusters in ceramics, but relatively little has been performed on defect agglomeration using transmission electron microscopy (TEM) in the same kind of detail that has been so successful in metals. This article will assess our present understanding of radiation damage in ceramics with illustrations using results obtained from the authors' work.

Convective Heat and Mass Transfer

2009 ◽  
Author(s):  
Mostafa Ghiaasiaan
Keyword(s):  
Mass Transfer ◽  
Heat And Mass Transfer ◽  
Convective Heat
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