Characterization and Quantification of Pore Water in Clays During Drying Process With Low-Field NMR

doi:10.1029/2020WR027537

	Characterization and Quantification of Pore Water in Clays During Drying Process With Low-Field NMR
	Tian, H. H.2; Wei, C. F.1,2
刊名	WATER RESOURCES RESEARCH
	2020-10-01
卷号	56 期号:10 页码:15
关键词	soil‐ water interaction water dynamics NMR surface relaxivity microstructure
ISSN号	0043-1397
DOI	10.1029/2020WR027537
英文摘要	Water transport in large-specific surface soil is controlled by soil microstructure and soil-water interaction. In this paper, soil-water interaction and confined water dynamics as well as soil microstructure are studied by combining the nuclear magnetic resonance technique and the mercury intrusion porosimetry. It is revealed that during a drying process pore water drainage occurs sequentially from larger pores to smaller pores, and surface interaction parameter rho(1) appears to be a well-defined quantity at a water content above one water layer, below which rho(1) shows a different trend. With the two-dimensional T-1-T-2 correlation measurements, surface dynamical parameters, including residence time and surface affinity coefficient, are determined, showing that the mobility of pore water decreases gradually with the decrease in water potential. The effect of temperature on the soil-water interaction is discussed via the variation of relaxation time with temperature. The increase in residence time and surface affinity coefficient as well as effective activation energy Delta E indicates that the mobility of pore water decreases with the decrease in water potential. In addition, the positiveness of Delta E indicates that unsaturated hydraulic conductivity of clay increases with temperature, and a larger Delta E implies that the unsaturated hydraulic conductivity for the sample equilibrated at smaller potential is more sensitive to the temperature. The average pore sizes of the saturated samples are also determined by the mercury intrusion porosimetry, showing clear consistency between the mercury intrusion porosimetry (MIP) and nuclear magnetic resonance (NMR) measurements.
资助项目	National Science Foundation of China (NSFC)[51939011] ; National Science Foundation of China (NSFC)[51639008] ; National Science Foundation of China (NSFC)[41502301] ; Guangxi Key Laboratory of New Energy and Building Energy Saving, Guilin University of Technology
WOS研究方向	Environmental Sciences & Ecology ; Marine & Freshwater Biology ; Water Resources
语种	英语
出版者	AMER GEOPHYSICAL UNION
WOS记录号	WOS:000586456800008
内容类型	期刊论文
源URL	[http://119.78.100.198/handle/2S6PX9GI/25025]
专题	中科院武汉岩土力学所
通讯作者	Wei, C. F.
作者单位	1.Guilin Univ Technol, Guangxi Key Lab Geomech & Geotech Engn, Guilin, Peoples R China 2.Chinese Acad Sci, Inst Rock & Soil Mech, State Key Lab Geomech & Geotech Engn, Wuhan, Peoples R China
推荐引用方式 GB/T 7714	Tian, H. H.,Wei, C. F.. Characterization and Quantification of Pore Water in Clays During Drying Process With Low-Field NMR[J]. WATER RESOURCES RESEARCH,2020,56(10):15.
APA	Tian, H. H.,&Wei, C. F..(2020).Characterization and Quantification of Pore Water in Clays During Drying Process With Low-Field NMR.WATER RESOURCES RESEARCH,56(10),15.
MLA	Tian, H. H.,et al."Characterization and Quantification of Pore Water in Clays During Drying Process With Low-Field NMR".WATER RESOURCES RESEARCH 56.10(2020):15.