Characteristic temperatures of saline soil during freezing
YING Sai1,2, ZHOU Feng-xi1, WEN Tao2, CAO Ya-peng3
1. College of Civil Engineering, Lanzhou University of Technology, Lanzhou 730000, China; 2. Engineering Research Center for Health Monitoring in Building Life Cycle and Disaster Prevention, Yangtze Normal University, Chongqing 408100, China; 3. State Key Laboratory of Frozen Soil Engineering, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
Abstract：The characteristic temperatures appearing in freezing process of saline soil include the freezing temperature and the supercooling temperature. The former is the point at which chemical potentials of ice and liquid achieve equilibrium, and the latter is the point of ice nucleation. The characteristic temperatures are important for the analysis of the freezing state of soil. In the beginning, the characteristic temperatures are obtained through the freezing tests on the saline soil with different salt contents. And then, a model for calculating the characteristic temperatures is provided based on the thermodynamics and the classical nucleation theory. The model is proved to be reliable by comparing the calculated data with the test data. Finally, the influence factors for the model are analyzed, and especially the influences of salt precipitation on the characteristic temperatures are considered. The results show that the proposed model can effectively predict the characteristic temperatures of the saline soil. The salt content corresponding to the salt precipitation can be acquired by the relationship curve between the characteristic temperatures and the salt contents of the saline soil. The freezing temperature has a negative correlation with the concentration of pore solution, and the salt precipitation will induce the depression of the concentration of pore solution so as to increase the freezing temperature. The reason for the increase of the supercooling temperature of the saline soil is the double-effect of the depression of solution concentration and the decrease of contact angle between ice and soil particles.
[1] 徐攸在. 盐渍土地基[M]. 北京: 中国建筑工业出版社, 2012. (XU You-zai.Saline Soil Foundation[M]. Beijing: China Architecture & Building Press, 2012. (in Chinese)) [2] WU D, LAI Y, ZHANG M.Heat and mass transfer effects of ice growth mechanisms in a fully saturated soil[J]. International Journal of Heat and Mass Transfer, 2015, 86: 699-709. [3] KONIORCZYK M, GAWIN D.Modelling of salt crystallization in building materials with microstructure: poromechanical approach[J]. Construction & Building Materials, 2012, 36: 860-873. [4] ESPINOSA R M, FRANKE L, DECKELMANN G.Model for the mechanical stress due to the salt crystallization in porous materials[J]. Construction and Building Materials, 2008, 22(7): 1350-1367. [5] ESPINOSA R M, FRANKE L, DECKELMANN G.Phase changes of salts in porous materials: crystallization, hydration and deliquescence[J]. Construction & Building Materials, 2008, 22(8):1758-1773. [6] SCHERER G W.Crystallization in pores[J]. Cement & Concrete Research, 1999, 29(8): 1347-1358. [7] SCHERER G W.Stress from crystallization of salt[J]. Cement & Concrete Research, 2004, 34(9): 1613-1624. [8] WANG C, LAI Y, YU F, et al.Estimating the freezing-thawing hysteresis of chloride saline soils based on the phase transition theory[J]. Applied Thermal Engineering, 2018, 135: 22-33. [9] KHVOROSTYANOV V I, CURRY J A.Thermodynamic theory of freezing and melting of water and aqueous solutions[J]. The Journal of Physical Chemistry A, 2004, 108(50): 11073-11085. [10] WU D, LAI Y, ZHANG M.Heat and mass transfer effects of ice growth mechanisms in a fully saturated soil[J]. International Journal of Heat and Mass Transfer, 2015, 86: 699-709. [11] 徐学祖, 王家澄, 张立新. 冻土物理学[M]. 科学出版社, 2001. (XU Xue-zu, WANG Jia-cheng, ZHANG Li-xin.Frozen Soil Physics[M]. Beijing: Science Press, 2001. (in Chinese)) [12] LAI Y, WU D, ZHANG M.Crystallization deformation of a saline soil during freezing and thawing processes[J]. Applied Thermal Engineering, 2017, 120: 463-473. [13] KONRAD J M.Temperature of ice lens formation in freezing soils[C]// Proceedings of 5th International Conference on Permafrost. Trondheim, Norway: Tapir Publishers. 1988: 384-389. [14] STYLE R W, PEPPIN S S L, COCKS A C F, et al. Ice-lens formation and geometrical supercooling in soils and other colloidal materials[J]. Physical Review E, 2011, 84(4): 041402. [15] 万旭升, 赖远明, 廖孟柯. 硫酸盐渍土未相变含水率与温度关系研究[J]. 岩土工程学报, 2015, 37(12): 2175-2181. (WAN Xu-sheng, LAI Yuan-ming, LIAO Meng-ke.Relationship between temperature and water content of sodium saline soils without phase transformation[J]. ChineseJournal of Geotechnical Engineering, 2015, 37(12): 2175-2181. (in Chinese)) [16] 邴慧, 马巍. 盐渍土冻结温度的试验研究[J]. 冰川冻土, 2011, 3(5): 1106-1113. (BING Hui, MA Wei.Experimental study on freezing point of saline soil[J]. Journal of Glaciology and Geocryology, 2011, 3(5): 1106-1113. (in Chinese)) [17] BING Hui, MA Wei.Laboratory investigation of the freezing point of saline soil[J]. Cold Regions Science & Technology, 2011, 67(1): 79-88. [18] 张婷, 杨平. 不同因素对浅表土冻结温度的影响[J]. 南京林业大学学报(自然科学版), 2009, 34(4): 136-138. (ZHANG Ting, YANG Ping.Effect of different factors on the freezing temperature of shallow top soil[J]. Journal of Nanjing Forestry University (Natural Science Edition), 2009, 33(4): 132-134. (in Chinese)) [19] 李毅, 崔广心, 吕恒林. 有压条件下湿黏土结冰温度的研究[J]. 冰川冻土, 1996, 18(1):43-46. (LI Yi, CUI Guang-xin, LÜ Heng-lin.A study on freezing point of wet clay under loading[J]. Journal of Glaciolgy & Geocryology, 1996, 18(1): 43-46. (in Chinese)) [20] 周家作, 谭龙, 韦昌富, 等. 土的冻结温度与过冷温度试验研究[J]. 岩土力学, 2015, 36(3): 777-785. (ZHOU Jia-zuo, TAN Long, WEI Chang-fu, et al.Experimental research on freezing temperature and super-cooling temperature of soil[J]. Rock and Soil Mechanics, 2015, 36(3): 777-785. (in Chinese)) [21] HAN Y, WANG Q, KONG Y, et al.Experiments on the initial freezing point of dispersive saline soil[J]. Catena, 2018, 171: 681-690. [22] WAN X, HU Q, LIAO M.Salt crystallization in cold sulfate saline soil[J]. Cold Regions Science and Technology, 2017, 137: 36-47. [23] XIAO Z, LAI Y, YOU Z, et al.The phase change process and properties of saline soil during cooling[J]. Arabian Journal for Science and Engineering, 2017, 42(9): 3923-3932. [24] PETROV O, FURÓ I.Curvature-dependent metastability of the solid phase and the freezing-melting hysteresis in pores[J]. Physical Review E, 2006, 73(1): 011608. [25] MORISHIGE K, KAWANO K.Freezing and melting of water in a single cylindrical pore: the pore-size dependence of freezing and melting behavior[J]. The Journal of Chemical Physics, 1999, 110(10): 4867-4872. [26] JIANG Q, WARD M D.Crystallization under nanoscale confinement[J]. Chemical Society Reviews, 2014, 43(7): 2066-2079. [27] SLIWINSKA-BARTKOWIAK M, GRAS J, SIKORSKI R.Phase transitions in pores: experimental and simulation studies of melting and freezing[J]. Langmuir, 1999, 15(18): 6060-6069. [28] 王中平, 王弢. 简述核磁共振冷冻测孔法的原理及应用[J]. 材料导报, 2013, 27(1): 129-133. (WANG Zhong-ping, WANG Tao.A brief introduction to the principle and application of nuclear magnetic resonance cryoporometry[J]. Materials Reports, 2013, 27(1): 129-133. (in Chinese)) [29] WAN X, LAI Y, WANG C.Experimental study on the freezing temperatures of saline silty soils[J]. Permafrost & Periglacial Processes, 2015, 26(2): 175-187. [30] XIAO Z, LAI Y, ZHANG M.Study on the freezing temperature of saline soil[J]. Acta Geotechnica, 2018, 13(1): 195-205. [31] KOZLOWSKI T .Some factors affecting supercooling and the equilibrium freezing point in soil-water systems[J]. Cold Regions ence & Technology, 2009, 59(1): 25-33. [32] STEIGER M.Crystal growth in porous materials—I: The crystallization pressure of large crystals[J]. Journal of Crystal Growth, 2005, 282(3/4): 455-469. [33] 周凤玺, 应赛, 蔡袁强. 多孔介质中晶体的结晶压力分析[J]. 岩土工程学报, 2019, 41(6): 1158-1163. (ZHOU Feng-xi, YING Sai, CAI Yuan-qiang.Crystallization pressure of crystals in porous media[J]. Chinese Journal of Geotechnical Engineering, 2019, 41(6): 1158-1163. (in Chinese)) [34] PITZER K S.Activity Coefficients in Electrolyte Solutions[M]. Boca Rton: CRC press, 2018. [35] 万旭升. 硫酸盐渍土盐晶体析出, 盐分迁移及寒区路基防盐胀试验研究[D]. 北京: 中国科学院大学, 2015. (WAN Xu-sheng.Labotory Investigation on Salt Crystals precipitation of Sulfate Saline Soil and Salt Transfer and Salt-Heaving Mitigation of Embankment in Cold Regions[D]. Beijing: University of Chinese Academy of Sciences, 2015. (in Chinese)) [36] STEIGER M.Crystal growth in porous materials—II: Influence of crystal size on the crystallization pressure[J]. Journal of Crystal Growth, 2005, 282(3/4):470-481. [37] MULLIN J W.Crystallization[M]. Oxford: Butterworth- Heinemann, 2001. [38] FLETCHER N H J. Size effect in heterogeneous nucleation[J]. The Journal of Chemical Physics, 1958, 29(3): 572-576. [39] 李星星, 王思敬, 肖锐铧, 等. 硫酸钠溶液在降温结晶过程中的盐胀与冻胀[J]. 岩土工程学报, 2016, 38(11): 2069-2077. (LI Xing-xing, WANG Si-jin, XIAO Rui-hua, et al.Saline expansion and frost heave of sodium sulfate solution during cooling crystallization process[J]. Chinese Journal of Geotechnical Engineering, 2016, 38(11): 2069-2077. (in Chinese))
