冻结过程中水分盐分结晶相变对盐渍土压力的影响

硅酸盐通报 ›› 2021, Vol. 40 ›› Issue (4): 1296-1303.

冻结过程中水分盐分结晶相变对盐渍土压力的影响

谭仁义^1,2, 吴道勇^1,2, 黄佑芬^1,3, 吴诗雨^1,3

1.喀斯特地质资源与环境教育部重点实验室,贵阳 550025;
2.贵州大学,国土资源部喀斯特环境与地质灾害重点实验室,贵阳 550025;
3.贵州大学资源与环境工程学院,贵阳 550025

收稿日期:2020-11-18 修回日期:2021-01-18 出版日期:2021-04-15 发布日期:2021-05-11
通讯作者: 吴道勇,博士,副教授。E-mail:dywu@gzu.edu.cn
作者简介:谭仁义(1993—),男,硕士研究生。主要从事盐渍土结晶方面的研究。E-mail:1033595534@qq.com
基金资助:
国家自然科学基金(41761016);贵州省科技计划项目(黔科合平台人才[2017]5788号)

Effects of Water and Salt Crystallization Phase Change on Saline Soil Pressure During Freezing Process

TAN Renyi^1,2, WU Daoyong^1,2, HUANG Youfen^1,3, WU Shiyu^1,3

1. Key Laboratory of Karst Geological Resources and Environment, Ministry of Education, Guiyang 550025, China;
2. Key Laboratory of Karst Environment and Geohazard, Ministry of Land and Resources, Guizhou University, Guiyang 550025, China;
3. College of Resource and Environment Engineering, Guizhou University, Guiyang 550025, China

Received:2020-11-18 Revised:2021-01-18 Online:2021-04-15 Published:2021-05-11

摘要/Abstract

摘要： 冻胀和盐胀导致土体变形破坏对建筑基础、公路铁路路基等构成严重威胁。本文开展了冻结过程中水分盐分结晶相变对盐渍土压力的影响试验研究,结果表明:冰晶压力随着含水率的增加而增大;在一定干密度和含水率下,盐结晶压力随着含盐量的增大而增大。冻结过程中,土压力首先保持不变,然后迅速增大,最后迅速降低至稳定。冰晶压力与盐结晶压力作为张应力作用在孔隙壁上使得土颗粒间相互挤压,达到峰值应力后,土体结构破坏和土颗粒重分布导致土压力迅速降低至稳定。此外,还讨论了传统盐结晶压力方程和冰晶压力方程的适用性,最后对冰晶压力方程进行了修正。

关键词: 盐渍土, 冻胀, 盐胀, 相变, 结晶压力, 土压力

Abstract: Soil deformation caused by frost heave and salt heave is a serious threat to building foundations, roads and railway subgrades. The effects of water and salt crystallization phase change on saline soil pressure during freezing process were studied experimentally. The results show that the ice crystallization pressure increases with the increase of moisture content, while salt crystallization pressure increases with the increase of salt content under a certain dry density and moisture content. During the freezing process, the soil pressure unchanges firstly, then increases rapidly, and finally decreases to stability. The analysis shows that the ice crystallization pressure and salt crystallization pressure act as tensile stress on the pore wall to squeeze the soil particles between each other, after the peak stress, the breaken of soil structure and redistribution of soil particles lead to the soil pressure rapidly decreases to stability. In addition, the applicability of the traditional salt crystallization pressure equation and ice crystallization pressure equation were discussed. Finally, the ice crystallization pressure equation was modified.

Key words: saline soil, frost heave, salt heave, phase change, crystallization pressure, soil pressure

中图分类号:

TU43

谭仁义, 吴道勇, 黄佑芬, 吴诗雨. 冻结过程中水分盐分结晶相变对盐渍土压力的影响[J]. 硅酸盐通报, 2021, 40(4): 1296-1303.

TAN Renyi, WU Daoyong, HUANG Youfen, WU Shiyu. Effects of Water and Salt Crystallization Phase Change on Saline Soil Pressure During Freezing Process[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2021, 40(4): 1296-1303.

参考文献

[1] 李生伟,杨超.冻融循环作用下盐渍土病害机理及改良技术综述[J].水利水电技术,2020,51(8):191-200.
LI S W, YANG C. Overreview on disease mechanism and improvement technology of saline soil under effect of freeze-thawing cycle[J]. Water Resources and Hydropower Engineering, 2020, 51(8): 191-200 (in Chinese).
[2] 杨鹏,朱彦鹏,曹亚鹏,等.含水率单次递减条件下粗颗粒硫酸盐渍土盐胀的室内模拟试验[J].岩土力学,2017,38(10):2909-2915.
YANG P, ZHU Y P, CAO Y P, et al. Experiment of salt expansion behavior for coarse saline soil containing sulphate due to drying[J]. Rock and Soil Mechanics, 2017, 38(10): 2909-2915 (in Chinese).
[3] 曹亚鹏,文桃,米海珍,等.硫酸盐渍土含水率单次递减条件下的盐胀特性[J].岩土力学,2018,39(3):881-888.
CAO Y P, WEN T, MI H Z, et al. Salt expansion properties of sulfate saline soils under one time decrease of water content[J]. Rock and Soil Mechanics, 2018, 39(3): 881-888 (in Chinese).
[4] 米海珍,刘志义,文桃,等.含细粒土夹层粗颗粒硫酸盐渍土盐胀实验分析[J].甘肃科学学报,2016,28(2):88-91+112.
MI H Z, LIU Z Y, WEN T, et al. The salt expansion experimental analysis on coarse-grained sulphate salty soil in fine-grained soil interlayer[J]. Journal of Gansu Sciences, 2016, 28(2): 88-91+112 (in Chinese).
[5] 张莎莎,王永威,包卫星,等.影响粗粒硫酸盐渍土盐胀特性的敏感因素研究[J].岩土工程学报,2017,39(5):946-952.
ZHANG S S, WANG Y W, BAO W X, et al. Sensitive parameters of embankment deformation behavior for coarse-grained sulfate saline soil[J]. Chinese Journal of Geotechnical Engineering, 2017, 39(5): 946-952 (in Chinese).
[6] 牛玺荣,高江平.综合考虑盐胀和冻胀时硫酸盐渍土体积变化关系式的建立[J].岩土工程学报,2015,37(4):755-760.
NIU X R, GAO J P. Expression for volume change of sulphate saline soil considering salt expansion and frost heave[J]. Chinese Journal of Geotechnical Engineering, 2015, 37(4): 755-760 (in Chinese).
[7] 周凤玺,王立业,赖远明.饱和盐渍土的一维蠕变试验与模型研究[J].岩土工程学报,2020,42(1):142-149.
ZHOU F X, WANG L Y, LAI Y M. One-dimensional creep tests and model studies on saturated saline soil[J]. Chinese Journal of Geotechnical Engineering, 2020, 42(1): 142-149 (in Chinese).
[8] ZHANG J, LAI Y M, LI J F, et al. Study on the influence of hydro-thermal-salt-mechanical interaction in saturated frozen sulfate saline soil based on crystallization kinetics[J]. International Journal of Heat and Mass Transfer, 2020, 146: 118868.
[9] 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 X S, LAI Y M, LIAO M K. Relationship between temperature and water content of sodium saline soils without phase transformation[J]. Chinese Journal of Geotechnical Engineering, 2015, 37(12): 2175-2181 (in Chinese).
[10] 冯瑞玲,蔡晓宇,吴立坚,等.硫酸盐渍土水-盐-热-力四场耦合理论模型[J].中国公路学报,2017,30(2):1-10+40.
FENG R L, CAI X Y, WU L J, et al. Theoretical model on coupling process of moisture-salt-heat-stress field in sulfate salty soil[J]. China Journal of Highway and Transport, 2017, 30(2): 1-10+40 (in Chinese).
[11] WU D Y, YANG Y G, ZHOU X Y, et al. An experimental study of heat and mass transfer in deformable sulfate saline soil during freezing[J]. Heat and Mass Transfer, 2019, 55(6): 1809-1817.
[12] CORRENS C W. Growth and dissolution of crystals under linear pressure[J]. Discussions of the Faraday Society, 1949, 5: 267.
[13] EVERETT D H. The thermodynamics of frost damage to porous solids[J]. Transactions of the Faraday Society, 1961, 57: 1541-1551.
[14] WAN X S, HU Q J, LIAO M K. Salt crystallization in cold sulfate saline soil[J]. Cold Regions Science and Technology, 2017, 137: 36-47.
[15] KOUDELKOVÁ V, WOLF B, HRBEK V, et al. Experimental measurement of disjoining force at the glass-salt interface: a direct evidence of salt degradation potential caused by crystallization pressure[J]. Journal of Cultural Heritage, 2020, 42: 1-7.
[16] LAI Y M, WU D Y, ZHANG M Y. Crystallization deformation of a saline soil during freezing and thawing processes[J]. Applied Thermal Engineering, 2017, 120: 463-473.
[17] STEIGER M, ASMUSSEN S. Crystallization of sodium sulfate phases in porous materials: the phase diagram Na₂SO₄-H₂O and the generation of stress[J]. Geochimica et Cosmochimica Acta, 2008, 72(17): 4291-4306.
[18] RIJNIERS L A, HUININK H P, PEL L, et al. Experimental evidence of crystallization pressure inside porous media[J]. Physical Review Letters, 2005, 94(7): 075503.
[19] 杨全兵,杨钱荣.硫酸钠盐结晶对混凝土破坏的影响[J].硅酸盐学报,2007,35(7):877-880+885.
YANG Q B, YANG Q R. Effects of salt-crystallization of sodium sulfate on deterioration of concrete[J]. Journal of the Chinese Ceramic Society, 2007, 35(7): 877-880+885 (in Chinese).
[20] WU D Y, LAI Y M, ZHANG M Y. Thermo-hydro-salt-mechanical coupled model for saturated porous media based on crystallization kinetics[J]. Cold Regions Science and Technology, 2017, 133: 94-107.