Permeability characteristics and structural evolution of compacted loess under different dry densities and wetting-drying cycles.

Permeability characteristics of compacted loess is always an important topic in soil mechanics and geotechnical engineering. This study explored the permeability characteristics of compacted loess under different dry densities and wetting-drying cycles, and found that as the dry density increases, t...

Descripción completa

Guardado en:

Detalles Bibliográficos
Autores principales:	Kang-Ze Yuan, Wan-Kui Ni, Xiang-Fei Lü, Xi-Jun Wang
Formato:	article
Lenguaje:	EN
Publicado:	Public Library of Science (PLoS) 2021
Materias:	Medicine R Science Q
Acceso en línea:	https://doaj.org/article/3bbb9076eb8d4fce9ef0b037805d8b51
Etiquetas:	Agregar Etiqueta Sin Etiquetas, Sea el primero en etiquetar este registro!

id	oai:doaj.org-article:3bbb9076eb8d4fce9ef0b037805d8b51
record_format	dspace
spelling	oai:doaj.org-article:3bbb9076eb8d4fce9ef0b037805d8b512021-12-02T20:09:53ZPermeability characteristics and structural evolution of compacted loess under different dry densities and wetting-drying cycles.1932-620310.1371/journal.pone.0253508https://doaj.org/article/3bbb9076eb8d4fce9ef0b037805d8b512021-01-01T00:00:00Zhttps://doi.org/10.1371/journal.pone.0253508https://doaj.org/toc/1932-6203Permeability characteristics of compacted loess is always an important topic in soil mechanics and geotechnical engineering. This study explored the permeability characteristics of compacted loess under different dry densities and wetting-drying cycles, and found that as the dry density increases, the compacted loess surface became denser, the saturation permeability coefficient and saturation infiltration rate decreased. However, the wetting-drying cycle presented the opposite result. Meanwhile, the evolution of the microstructure was investigated by Scanning Electron Microscope (SEM) and Nuclear Magnetic Resonance (NMR) to explain the change of its permeability characteristics. The size of compacted loess aggregates was quantitatively analyzed by Image-Pro Plus (IPP) software. It showed that the size of compacted loess aggregates for different dry densities were concentrated from 10-100 μm, occupying 65.0%, 58.19%, and 51.64% of the total aggregates area respectively. And the interesting finding was that the area occupied by 10-50 μm aggregates remained basically unchanged with the number of wetting-drying cycles increasing. Therefore, the size of 10-50 μm aggregates represented the transition zone of compacted loess. NMR analyses revealed that with increasing dry density, the volume of macropores in the compacted loess rapidly decreased, the volume of mesopores and small pores increased. Meanwhile, the change in micropores was relatively small. The pore volume of the compacted loess after three wetting-drying cycles increased by 8.56%, 8.61%, and 6.15%, respectively. The proportion of macropores in the total pore volume shows the most drastic change. Variations in aggregate size and connection relationships made it easier to form overhead structures between aggregates, and the increased of macropore volume will form more water channels. Therefore, the change in permeability characteristics of compacted loess is determined by aggregate size, loess surface morphology, and the total pore volume occupied by macropores.Kang-Ze YuanWan-Kui NiXiang-Fei LüXi-Jun WangPublic Library of Science (PLoS)articleMedicineRScienceQENPLoS ONE, Vol 16, Iss 6, p e0253508 (2021)
institution	DOAJ
collection	DOAJ
language	EN
topic	Medicine R Science Q
spellingShingle	Medicine R Science Q Kang-Ze Yuan Wan-Kui Ni Xiang-Fei Lü Xi-Jun Wang Permeability characteristics and structural evolution of compacted loess under different dry densities and wetting-drying cycles.
description	Permeability characteristics of compacted loess is always an important topic in soil mechanics and geotechnical engineering. This study explored the permeability characteristics of compacted loess under different dry densities and wetting-drying cycles, and found that as the dry density increases, the compacted loess surface became denser, the saturation permeability coefficient and saturation infiltration rate decreased. However, the wetting-drying cycle presented the opposite result. Meanwhile, the evolution of the microstructure was investigated by Scanning Electron Microscope (SEM) and Nuclear Magnetic Resonance (NMR) to explain the change of its permeability characteristics. The size of compacted loess aggregates was quantitatively analyzed by Image-Pro Plus (IPP) software. It showed that the size of compacted loess aggregates for different dry densities were concentrated from 10-100 μm, occupying 65.0%, 58.19%, and 51.64% of the total aggregates area respectively. And the interesting finding was that the area occupied by 10-50 μm aggregates remained basically unchanged with the number of wetting-drying cycles increasing. Therefore, the size of 10-50 μm aggregates represented the transition zone of compacted loess. NMR analyses revealed that with increasing dry density, the volume of macropores in the compacted loess rapidly decreased, the volume of mesopores and small pores increased. Meanwhile, the change in micropores was relatively small. The pore volume of the compacted loess after three wetting-drying cycles increased by 8.56%, 8.61%, and 6.15%, respectively. The proportion of macropores in the total pore volume shows the most drastic change. Variations in aggregate size and connection relationships made it easier to form overhead structures between aggregates, and the increased of macropore volume will form more water channels. Therefore, the change in permeability characteristics of compacted loess is determined by aggregate size, loess surface morphology, and the total pore volume occupied by macropores.
format	article
author	Kang-Ze Yuan Wan-Kui Ni Xiang-Fei Lü Xi-Jun Wang
author_facet	Kang-Ze Yuan Wan-Kui Ni Xiang-Fei Lü Xi-Jun Wang
author_sort	Kang-Ze Yuan
title	Permeability characteristics and structural evolution of compacted loess under different dry densities and wetting-drying cycles.
title_short	Permeability characteristics and structural evolution of compacted loess under different dry densities and wetting-drying cycles.
title_full	Permeability characteristics and structural evolution of compacted loess under different dry densities and wetting-drying cycles.
title_fullStr	Permeability characteristics and structural evolution of compacted loess under different dry densities and wetting-drying cycles.
title_full_unstemmed	Permeability characteristics and structural evolution of compacted loess under different dry densities and wetting-drying cycles.
title_sort	permeability characteristics and structural evolution of compacted loess under different dry densities and wetting-drying cycles.
publisher	Public Library of Science (PLoS)
publishDate	2021
url	https://doaj.org/article/3bbb9076eb8d4fce9ef0b037805d8b51
work_keys_str_mv	AT kangzeyuan permeabilitycharacteristicsandstructuralevolutionofcompactedloessunderdifferentdrydensitiesandwettingdryingcycles AT wankuini permeabilitycharacteristicsandstructuralevolutionofcompactedloessunderdifferentdrydensitiesandwettingdryingcycles AT xiangfeilu permeabilitycharacteristicsandstructuralevolutionofcompactedloessunderdifferentdrydensitiesandwettingdryingcycles AT xijunwang permeabilitycharacteristicsandstructuralevolutionofcompactedloessunderdifferentdrydensitiesandwettingdryingcycles
_version_	1718375056252338176

Permeability characteristics and structural evolution of compacted loess under different dry densities and wetting-drying cycles.

Ejemplares similares