基于广义Clapeyron方程的含盐土冻结特征曲线模型  

Freezing characteristic curve model of saline soil based on generalized Clapeyron equation

作　　者：孟祥传 周家作[2] 韦昌富[1,2] 陈盼[2] 张坤 沈正艳 MENG Xiang-chuan;ZHOU Jia-zuo;WEI Chang-fu;CHEN Pan;ZHANG Kun;SHEN Zheng-yan(College of Civil Engineering and Architecture,Guilin University of Technology,Guilin 541004,China;State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,China;Key Laboratory of Bridge and Tunnel Health Monitoring and Safety Assessment Technology of Gansu Province,Gansu Provincial Transportation Research Institute Co.Ltd,Lanzhou 730030,China;School of Mechanics and Civil Engineering,China University of Mining and Technology,Beijing 100083,China)

机构地区：[1]桂林理工大学土木与建筑工程学院,广西桂林541004 [2]中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室,湖北武汉430071 [3]甘肃省交通科学研究院有限公司甘肃省桥梁隧道健康监测与安全评估技术重点实验室,甘肃兰州730030 [4]中国矿业大学力学与建筑工程学院,北京100083

出　　处：《浙江大学学报（工学版）》2020年第12期2377-2385,共9页Journal of Zhejiang University：Engineering Science

基　　金：国家自然科学基金资助项目(41572293,41602312)。

摘　　要：未冻水质量分数是评估盐渍土和滨海地区土体冻结过程地层稳定性的关键参数,其主要影响因素为温度和盐的质量分数.基于考虑溶质效应的广义Clapeyron方程,通过无盐分土冻结特征曲线得到冻土吸力的微分形式,联合考虑残余水的质量分数的Books-Corey模型,推导出在任意盐的质量分数和温度条件下冻土中未冻水质量分数的理论模型.开展冻结试验,利用核磁共振法获得不同水的质量分数、盐的质量分数下粉质黏土和粉土的冻结特征曲线.试验结果表明:未冻水质量分数随温度降低呈指数函数递减,在同一温度下未冻水质量分数随着初始溶液浓度的增加近似呈线性增加,不同初始水的质量分数下的无盐土体冻结特征曲线具有一致性,粉土相对于粉质黏土更容易达到残余状态.将理论模型与试验数据进行对比,验证了该模型能够较为合理地预测含盐土体的冻结特征曲线.The unfrozen water mass fraction is the key parameter to evaluate the stability of the soil during the freezing process of saline and coastal areas.The main influencing factors are temperature and salt mass fraction.The differential form of matric suction of frozen soil was obtained by the freezing characteristic curve of salt-free soil,based on the generalized Clapeyron equation considering solute effect,and the Books-Corey model with residual water mass fraction.A theoretical model of soil freezing characteristic curve were derived for frozen soil under arbitrary salt mass fraction and temperature conditions.The freezing test was carried out,and the freezing characteristic curves of silty clay and silt under different water mass fraction and salt mass fraction were obtained by nuclear magnetic resonance.The results show that the mass fraction of unfrozen water decreases exponentially with the reduction of temperature.The unfrozen water mass fraction increases linearly with the increasement of initial solution concentration at the same temperature.The freezing characteristic curves of salt-free soil with different initial water mass fraction are consistent.The silt reaches the residual state more easily than the silty clay.It is verified that the model can predict the freezing characteristic curve of saline soil reasonably by comparing the theoretical model with the test data.

关 键 词：未冻水质量分数 化学势 核磁共振 残余水的质量分数 Clapeyron方程 

分 类 号：TU445[建筑科学—岩土工程]