Thermal-water-salt coupling process of unsaturated saline soil under unidirectional freezing

作     者：LUO Chong-liang YU Yun-yan ZHANG Jing TAO Jing-yan OU Qing-jie CUI Wen-hao LUO Chong-liang;YU Yun-yan;ZHANG Jing;TAO Jing-yan;OU Qing-jie;CUI Wen-hao

作者机构：School of Civil EngineeringLanzhou Jiaotong UniversityLanzhou 730070China School of Civil EngineeringHexi UniversityZhangye 734000China State Key Laboratory of Frozen Soil EngineeringNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China 

出 版 物：《Journal of Mountain Science》 (山地科学学报（英文）)

年 卷 期：2023年第20卷第2期

页      面：557-569页

核心收录：

学科分类：082802[工学-农业水土工程] 090707[农学-水土保持与荒漠化防治] 0907[农学-林学] 08[工学] 0828[工学-农业工程] 09[农学] 0815[工学-水利工程] 

基　　金：supported by the Special Funds for Guiding Local Scientific and Technological Development by The Central Government(22ZY1QA005) the Science and Technology Program of Gansu Province"Outstanding Doctoral Students Project"(22JR5RA325) "Innovation Star"Funding Project for Outstanding Graduate Students of Gansu Province(2022CXZX-528) the Science and Technology Project of Gansu Province(21YF5GA050) Education Department of Gansu Province Industrial Support Plan Project(2021CYZC-28) Transport Department of Gansu Province Science and Technology R&D Projects(No.2021-12) 

主　　题：Unsaturated sulfate saline soil Watersalt migration Crystallization latent heat Crystallization impedance Mathematical model 

摘      要：Salinization and desertification are closely related to water-salt migration caused by a temperature *** on the Darcy Law of unsaturated soils,the law of energy conservation and the law of mass conservation,the thermal-water-salt coupling mathematical model of unsaturated frozen saline soil was *** model considered the latent heat of phase change,crystallization impedance,crystallization consumption and complete precipitation of solute crystallization in *** order to verify the rationality of the model,the unidirectional freezing test of unsaturated saline soil was carried out in an open system with no-pressure water supplement to obtain the spatial distribution of temperature,moisture and salt in the saline ***,numerical simulations are implemented with the assistance of COMSOL *** of the model is illustrated by comparisons between the simulation and experimental *** results demonstrated that the temperature within saline soil changes with time and can be divided into three stages,namely quick freezing stage,transitional stage and stable *** water and salt contents in the freezing zone are layered,with peak values at the freezing *** coupled model could reveal the heat-mass migration mechanism of unsaturated frozen saline soil and dynamically describe the freezing depth and the movement law of the freezing front,ice and salt crystal formation mechanism,and the change law of thermal conductivity and permeability coefficient.