Multiscale analysis of pore structure in clay due to freeze-thaw
The variation of pore structure due to freeze-thaw (F-T) plays a vital role in revealing the thaw settlement mechanism of soils. In this study, remolded saturated clay specimens experienced unidirectional freezing and natural thawing in an open or closed system (i.e., with or without water supply)....
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| Format: | Article |
| Language: | English |
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Elsevier
2023-12-01
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| Series: | Case Studies in Construction Materials |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S2214509523004539 |
| _version_ | 1827636291485827072 |
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| author | Wenhu Fan Ping Yang Shengfu Wang Xi Zuo Yingying Chen |
| author_facet | Wenhu Fan Ping Yang Shengfu Wang Xi Zuo Yingying Chen |
| author_sort | Wenhu Fan |
| collection | DOAJ |
| description | The variation of pore structure due to freeze-thaw (F-T) plays a vital role in revealing the thaw settlement mechanism of soils. In this study, remolded saturated clay specimens experienced unidirectional freezing and natural thawing in an open or closed system (i.e., with or without water supply). X-ray computed tomography (CT) and mercury intrusion porosimetry (MIP) were conducted to analyze pore structural characteristics, including macropores, mesopores, and micropores, along the temperature gradient direction before and after F-T. The longitudinal pore binary images, obtained by processing CT images, were used to assess the changes in porosity, pore shape, and orientation of macropores and mesopores due to F-T. The results indicate that the total longitudinal-sectional porosity and macropore percentage increased, whereas the mesopore percentage decreased. F-T considerably influenced the shape and orientation of macropores but had minimal effects on mesopores. The most significant changes occurred in the unfrozen zone due to F-T in an open system but near the final freezing front in a closed system. Additionally, Micropore porosity, diameter, and thermal fractal dimension were analyzed based on MIP data. The results showed that micropore porosity and diameter decreased, with significant changes occurring in the unfrozen zone of the open and closed systems. The micropore porosity and diameter decreased more in the unfrozen zone and near the final freezing front after F-T in a closed system, whereas a smaller decrease occurred in the frozen zone. The thermal fractal dimension value increases after F-T, indicating that the micropore structure became complex. In general, the multiscale pore analysis demonstrated that pore structure, including macropores, mesopores, and micropores, is significantly affected by F-T in the open system compared to the closed system. |
| first_indexed | 2024-03-09T15:39:59Z |
| format | Article |
| id | doaj.art-85e4bff39fd14d4d9a1d4b62da461a99 |
| institution | Directory Open Access Journal |
| issn | 2214-5095 |
| language | English |
| last_indexed | 2024-03-09T15:39:59Z |
| publishDate | 2023-12-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Case Studies in Construction Materials |
| spelling | doaj.art-85e4bff39fd14d4d9a1d4b62da461a992023-11-25T04:48:06ZengElsevierCase Studies in Construction Materials2214-50952023-12-0119e02273Multiscale analysis of pore structure in clay due to freeze-thawWenhu Fan0Ping Yang1Shengfu Wang2Xi Zuo3Yingying Chen4School of Architectural Engineering, Jinling Institute of Technology, Nanjing, Jiangsu Province 211169, China; School of Civil Engineering, Nanjing Forestry University, Nanjing, Jiangsu Province 210037, China; Correspondence to: School of Architectural Engineering, Jinling Institute of Technology, No. 99 Hongjing Road, Nanjing, Jiangsu Province 211169, China.School of Civil Engineering, Nanjing Forestry University, Nanjing, Jiangsu Province 210037, ChinaSchool of Civil & Architecture Engineering, East China University of Technology, Nanchang, Jiangxi Province 330013, ChinaSchool of Architectural Engineering, Jinling Institute of Technology, Nanjing, Jiangsu Province 211169, ChinaSchool of Architectural Engineering, Jinling Institute of Technology, Nanjing, Jiangsu Province 211169, ChinaThe variation of pore structure due to freeze-thaw (F-T) plays a vital role in revealing the thaw settlement mechanism of soils. In this study, remolded saturated clay specimens experienced unidirectional freezing and natural thawing in an open or closed system (i.e., with or without water supply). X-ray computed tomography (CT) and mercury intrusion porosimetry (MIP) were conducted to analyze pore structural characteristics, including macropores, mesopores, and micropores, along the temperature gradient direction before and after F-T. The longitudinal pore binary images, obtained by processing CT images, were used to assess the changes in porosity, pore shape, and orientation of macropores and mesopores due to F-T. The results indicate that the total longitudinal-sectional porosity and macropore percentage increased, whereas the mesopore percentage decreased. F-T considerably influenced the shape and orientation of macropores but had minimal effects on mesopores. The most significant changes occurred in the unfrozen zone due to F-T in an open system but near the final freezing front in a closed system. Additionally, Micropore porosity, diameter, and thermal fractal dimension were analyzed based on MIP data. The results showed that micropore porosity and diameter decreased, with significant changes occurring in the unfrozen zone of the open and closed systems. The micropore porosity and diameter decreased more in the unfrozen zone and near the final freezing front after F-T in a closed system, whereas a smaller decrease occurred in the frozen zone. The thermal fractal dimension value increases after F-T, indicating that the micropore structure became complex. In general, the multiscale pore analysis demonstrated that pore structure, including macropores, mesopores, and micropores, is significantly affected by F-T in the open system compared to the closed system.http://www.sciencedirect.com/science/article/pii/S2214509523004539X-ray computed tomography (CT)Mercury intrusion porosimetry (MIP)Freeze-thaw (F-T)Pore structureClay |
| spellingShingle | Wenhu Fan Ping Yang Shengfu Wang Xi Zuo Yingying Chen Multiscale analysis of pore structure in clay due to freeze-thaw Case Studies in Construction Materials X-ray computed tomography (CT) Mercury intrusion porosimetry (MIP) Freeze-thaw (F-T) Pore structure Clay |
| title | Multiscale analysis of pore structure in clay due to freeze-thaw |
| title_full | Multiscale analysis of pore structure in clay due to freeze-thaw |
| title_fullStr | Multiscale analysis of pore structure in clay due to freeze-thaw |
| title_full_unstemmed | Multiscale analysis of pore structure in clay due to freeze-thaw |
| title_short | Multiscale analysis of pore structure in clay due to freeze-thaw |
| title_sort | multiscale analysis of pore structure in clay due to freeze thaw |
| topic | X-ray computed tomography (CT) Mercury intrusion porosimetry (MIP) Freeze-thaw (F-T) Pore structure Clay |
| url | http://www.sciencedirect.com/science/article/pii/S2214509523004539 |
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