Pressures developed in a porous granular system as a result of ice segregation
Expansion of water when it freezes accounts for only a small fraction of total heave; a large percentage of the displacement in soils is attributed to the freezing of transported water from below the freezing plane. Previous experiments showed that the magnitude of soil moisture tension when the gro...
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| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
1959
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| Online Access: | https://nrc-publications.canada.ca/eng/view/ft/?id=a64c558d-2065-4569-bca4-09d68b2b2c3b https://nrc-publications.canada.ca/eng/view/object/?id=a64c558d-2065-4569-bca4-09d68b2b2c3b https://nrc-publications.canada.ca/fra/voir/objet/?id=a64c558d-2065-4569-bca4-09d68b2b2c3b |
| Summary: | Expansion of water when it freezes accounts for only a small fraction of total heave; a large percentage of the displacement in soils is attributed to the freezing of transported water from below the freezing plane. Previous experiments showed that the magnitude of soil moisture tension when the growth of the ice lens stops depends on pore size dimension. This paper is devoted to the determination of the effect of overburden pressure and suction. The material used was powdered quartz. Samples were molded in the Harvard Miniature Compaction apparatus. Saturation before freezing was achieved by permitting de- aired water to enter one end of the specimen. Freezing was done unidirectionally with the cold side temperature at -3 degrees C and a warm side temperature of +1 1/2 degrees C. Maximum soil moisture tension determinations when heaving stopped were carried out at overburden pressures of 23, 229 and 535 grms/cm[2]. All experiments were carried out at three different dry densities between 1.592 and 1.750 gm/cm[ 3]. The results showed that the state of saturation of the unfrozen soil was linearly related to the overburden pressure used; i.e. the higher the overburden pressure the higher the moisture content below the freezing plane at the point where ice lensing stopped and hence the lower the soil moisture tension. These results are supported by theoretical considerations using the Clapeyron equation. L'expansion de l'eau qui gèle ne constitue qu'une faible fraction du soulèvement total du sol; le déplacement du sol est en grande partie attribuable au gel de l'eau provenant d' une profondeur inférieure au plan de gel. Le présent document porte sur la détermination de l'effet de la pression de surcharge et de la succion. Pour ce faire, on a utilisé du quartz réduit en poudre. Les résultats ont montré que l'état de saturation du sol non gelé est liné airement lié à la pression de surcharge utilisée, en d' autres termes, plus la pression de surcharge est élevée, plus la teneur en humidité l'est sous le plan de ... |
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