Effect of freeze–thaw cycling on the soil‐freezing characteristic curve of five Canadian soils

Abstract

The frozen soil processes and their interaction with the environment in the vadose zone of cold regions is vital in both agricultural and engineering practice applications. In a frozen soil, unfrozen water and pore ice coexist. The relationship between the unfrozen water content and subzero temperature is widely known as the soil-freezing characteristic curve (SFCC). The SFCC is a valuable tool for predicting the hydromechanical properties and for modeling the coupled thermal-hydraulic-mechanicalchemical process in frozen soils. In spite of its importance, the effect of freeze-thaw (F-T) cycling on SFCC has not been well investigated or understood. In this technical note, the effect of F-T cycles on the SFCC of five soils from cold regions of Canada were investigated. The SFCC (including both freezing and thawing branches) of the five soils for different F-T cycles were measured using frequency domain reflectometry (FDR) technique. The experimental results suggest that the effect of F-T cycles on the SFCC of the five soils is not significant. Such a behavior may be attributed to the destruction of soil structure during the saturation process. However, all the five soils' SFCC exhibited hysteresis behavior for all the F-T cycles. The results of the study are valuable and contribute towards better understanding of the fundamental behavior of SFCC of various cold region soils.

Impact of freeze-thaw cycles on organic carbon and metals in waters of permafrost peatlands

“…Since the 1970s, a lot of attention is given to the impact of freezing and thawing on soil properties (DeLuca et al, 1992;Kim et al, 2017;Larsen et al, 2002;Ren and Vanapalli, 2020;Schimel and Clein, 1996;Xiao et al, 2019). In contrast, studies on the influence of freezing and thawing on dissolved solutes of continental waters are only at their beginning (Chen et al, 2016;Hentschel et al, 2008;Pokrovsky et al, 2018;Savenko et al, 2020;Spencer et al, 2007).…”

A Model for the Soil Freezing Characteristic Curve That Represents the Dominant Role of Salt Exclusion

“… is the temperature at which a stable ice nucleus for ice crystallization forms in a freezing soil (Kozlowski, 2009). After reaching the there is a release of latent heat that warms the soil to its freezing point where freezing begins (Kozlowski, 2009; Ren & Vanapalli, 2020; Zhou et al., 2020). The supercooling effect is absent in the thawing curves (Figures 4b and 5b), which is as expected.…”

“…Given that real soils do contain solutes this would seem to be a limitation with GCE based models, however, the relative significance of solute effects and capillary effects is not well documented or understood (Watanabe & Mizoguchi, 2002). There are extensive SFC datasets in the literature, from early work by Koopmans and Miller (1966) and Williams (1970) through to recent experimental work by Caicedo (2017), Schafer and Beier (2017), and Ren and Vanapalli (2019), (2020), and including papers where the solute effects are quantified (e.g., Patterson & Smith, 1985; Zhou et al., 2018). To validate the GCE model requires both observed SFC and SMC data, which are not present in all of these studies.…”

A framework for constructing elasto‐plastic constitutive models for frozen and unfrozen soils

“…Figure 2 compares the calculated volumetric ice fraction using Equation 18 with measured data of different soils in the literature 105–107 . For the volumetric ice fraction profiles of the two sands with $$\chi =1$$, the smaller the value of parameter a , the steeper the curve, as shown in Figures 2A‐2B.…”

“…As a result, ϑ can be regarded as the second independent variable that plays the same role as the pore ice ratio used by Zhang and Michalowski 3 . Since the experimental data are from different sources for different soils in both freezing process 106 and thawing process 107 , the values of T f presented in Figures 2E‐2F actually represent both freezing and thawing temperatures. However, for the sake of simplicity, we assumed that they are equal for one particular soil with the freeze‐thaw hysteresis effect being neglected.…”