Dependence of Freezing Soil Heaving Properties on the Degree and Composition of Salinization

Ground freezing has been broadly applied to construction and maintenance works of infrastructures because of its environmental friendliness. Since freezing technology represented by ground freezing can improve the strength of soil as well as its water-tightness, it becomes an essential technology for construction and maintenance of urban infrastructures where the use of space in underground has already been highly integrated. In this paper, overview of the freezing technology is introduced with some important characteristics of freezing soil for practical application. In addition, freezing technology is used for interesting works which could not be completed without freezing, and the state of the arts in freezing technology is presented. A pipe-in-pipe, now the authors are developing, is an example to utilize the potential of frozen sand, and the effect of freezing is explained with experimental results.

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Snowpack Ion Accumulation and Loss in a Basin Draining to Lake Superior

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f87-225 ◽

1987 ◽

Vol 44 (11) ◽

pp. 1812-1819 ◽

Cited By ~ 10

Author(s):

Robert Stottlemyer

Keyword(s):

Lake Superior ◽

Ionic Species ◽

Winter Precipitation ◽

Stream Chemistry ◽

Order Stream ◽

Freezing Soil ◽

First Order ◽

Stream Discharge ◽

Biological Uptake ◽

Thaw Period

The objective of this study was to relate winter precipitation ionic inputs, snowpack retention, and change in first-order stream chemistry with spring snowpack melt. During winter 1982–83, measurement of precipitation inputs, snowpack concentration and loading, and streamwater concentration and discharge of Ca2+, K+, H+, NO3−, and SO42− from a 176-ha watershed reveals that only H+ might be lost from the snowpack before first thaw. Above-freezing soil temperature beneath the snowpack may be a factor in H+ loss. An initial 1-d thaw resulted in loss of over one third (6 eq∙ha−1) of the snowpack Ca2+. Over one half the snowpack load of K+, H+, NO3−, and SO42−, was lost in a subsequent midwinter freeze–thaw period. Snowpack loading of ionic species was reduced by 70–90% before peak spring melting and stream discharge. Ecosystem H+ retention and biological uptake of NO3− further mitigate ionic "pulses" in streamwater. Sulfate discharge exceeds bulk inputs, which suggests significant dry deposition input and little forest soil retention of this anion. The snowpack was relatively small, which limits wider application of these results to the region.

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A mechanistic theory of ice lens formation in fine-grained soils

Canadian Geotechnical Journal ◽

10.1139/t80-056 ◽

1980 ◽

Vol 17 (4) ◽

pp. 473-486 ◽

Cited By ~ 197

Author(s):

Jean-Marie Konrad ◽

Norbert R. Morgenstern

Keyword(s):

Steady State ◽

Heat Flow ◽

Freezing Temperature ◽

Cold Side ◽

Freezing Soil ◽

Fine Grained ◽

Mechanistic Theory ◽

Two Parameters ◽

Lens Formation

This study reveals that a freezing soil can be characterized by two parameters, the segregation-freezing temperature Ts and the overall permeability of the frozen fringe [Formula: see text]. During unsteady heat flow, the variation of these parameters with temperature produces rhythmic ice banding in fine-grained soils. At the onset of steady-state conditions, freezing tests conducted at a fixed warm end temperature showed that Ts was independent of the cold side step temperature. In addition, a model is presented that indicates how the overall permeability of the frozen fringe can be calculated without detailed measurements at the scale of the frozen fringe. It is also constant in the tests reported here.

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