Frost heaving

The molecular structure and dynamics of the ice/water interface are of interest, for example, in understanding phenomena like frost heaving, freezing (and the inhibition of freezing) in biological systems, and the growth mechanisms of ice crystals. In a series of simulations, Haymet and coworkers (see Refs. 193-196) studied the density variation, the orientational order and the layer-dependence of the mobilitity of water molecules. The ice/water basal interface is found to be a relatively broad interface of about... 

Frost heave may damage foundations of plant structures... 

Frost-heave is prevented hy supplying low-intensity heat to the underside of the insulation, to keep it above freezing point. This may take several forms ... 

EXAMPLE 4.2 Post hole depth to avoid frost heave (solution to the diffusion equation with oscillating boundary conditions)... 

The primary reason to place a post at deeper depths in the northern midwest is frost heave. The post hole needs to be below the frost line. What is this depth in each city ... 

In addition, the thermal diffusivity of the soil at both locations varies from a = 10 to 0 = 10 m /s. The post hole depth must be below the frost line, so that we do not have frost heave on our posts. The frost line would be at the depth where temperature never goes below freezing, T = 0°C. We should set the cosine term from equation (E4.2.2) to -1 and set the temperature to 0°C to determine this depth ... 

Comparison of equations (E4.2.16) and (E4.2.17) explains the origin of the difference in post hole depth between Boston and St. Paul. In Boston, post hole depth is that required for structural stabihty. In St. Paul, it is about avoiding frost heave. It is also interesting to note from Figure E4.2.1 that the temperature fluctuations at a depth of 1 m are damped by 1/e, or 0.37, and the lag in the peak of temperature is r = Xz/n or 1 /(2jt) years. The minimum temperature at a depth of 1 m appears almost 2 months after it is present at the surface. 

S.H. He, M.M. Mench, One-dimensional transient model for frost heave in polymer electrolyte fuel cells. J. Electrochem. Soc. 153, A1724—A1731 (2006)... 

Beskow, G., Soil Freezing and Frost Heaving with Special Applications... 

Vertical displacement of the lining from frost heave... 

Oulfur foam can be used to protect the permafrost by using a combina- tion of sulfur foam and local embankment materials for road, airfield, and other construction to reduce both the overall cost and the amount of embankment material that needs to be quarried in the arctic wilderness. The use of sulfur foam as subbase insulation prevents thawing of permafrost, which can cause subsidence during the warmer months. Another application uses sulfur foam with conventional pavement construction material for subbase insulation in frost-susceptible areas to prevent frost heave which is caused by freezing of the underlying soil. 

Foam SUDIC-Chevron Field Test for Frost Heave Prevention, Proc. Ann. Conf. Can. Tech. Asphalt Assoc., 20th (1975) 20, 195-210. 

Furthermore, there are other instances (multiple colloids) that may involve the co-existence of three phases of which two (and sometimes three) phases are finely divided. One example is a porous solid partially filled with condensed vapour, when both the liquid and vapour phases within the pores are present in a finely divided form a similar situation arises when oil and water co-exist in the pores of an oil-bearing rock, also in frost heaving when water and ice co-exist in a porous medium. Multiple emulsions consist for example of finely divided droplets of an aqueous phase contained within oil droplets, which themselves arc dispersed in an aqueous medium. 

Frost heaving Porous rock or soil Ice Water... 

Jones, Developments in the British Approach to prevention of frost heave in pavements , Transportation Research Record 1146, Transportation Research Board, Washington, 1987. 

Assesses susceptibility of compacted soil to frost heave Physical and chemical tests for aiding the selection and assessing the suitability of materials to act as bound and unbound aggregates... 

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