Strength and dilatancy of an unsaturated expansive soil at high suction levels
A series of suction-controlled triaxial tests was conducted on Nanyang expansive clay to investigate the effects of dry density and suction on dilatancy and strength. The suction of the soil samples was controlled using a vapour equilibrium technique, with four suction levels ranging from 3.29 MPa t...
Saved in:
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Elsevier
2025-08-01
|
| Series: | Journal of Rock Mechanics and Geotechnical Engineering |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S1674775524004979 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1849335671913709568 |
|---|---|
| author | Ke Chen Xuzhen He Fayun Liang Daichao Sheng |
| author_facet | Ke Chen Xuzhen He Fayun Liang Daichao Sheng |
| author_sort | Ke Chen |
| collection | DOAJ |
| description | A series of suction-controlled triaxial tests was conducted on Nanyang expansive clay to investigate the effects of dry density and suction on dilatancy and strength. The suction of the soil samples was controlled using a vapour equilibrium technique, with four suction levels ranging from 3.29 MPa to 198.14 MPa, where water retention is dominated by adsorption. The experimental results show that the tested soil exhibits a brittle failure mode under high suction, significantly distinguishing the hydro-mechanical behaviour of the soil at high suction from that observed at low suction. This brittle failure mode significantly increases the contribution of suction to peak strength compared to residual strength, causes the soil to fail before reaching the critical state, a phenomenon not observed in soils under high suction, and results in dilatancy caused by damage to the soil particle aggregates rather than particle rearrangement. The dilatancy data obtained from the triaxial tests reveal that significant soil dilatancy occurs during shear after reaching peak strength, with the maximum dilatancy angle increasing with suction and decreasing with confining pressure. However, the initial dry density has a negligible impact on the soil's dilatancy under high suction levels. This observation further supports that, for unsaturated soils under high suction levels, dilatancy is attributed to damage to soil particle aggregates rather than the rearrangement of soil particles. |
| format | Article |
| id | doaj-art-552266a39b404d45945d49cdb291a8fe |
| institution | Kabale University |
| issn | 1674-7755 |
| language | English |
| publishDate | 2025-08-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Journal of Rock Mechanics and Geotechnical Engineering |
| spelling | doaj-art-552266a39b404d45945d49cdb291a8fe2025-08-20T03:45:11ZengElsevierJournal of Rock Mechanics and Geotechnical Engineering1674-77552025-08-011785079508810.1016/j.jrmge.2024.05.061Strength and dilatancy of an unsaturated expansive soil at high suction levelsKe Chen0Xuzhen He1Fayun Liang2Daichao Sheng3Department of Geotechnical Engineering, Tongji University, Shanghai, 200092, China; School of Civil and Environmental Engineering, University of Technology Sydney, Ultimo, NSW 2007, AustraliaSchool of Civil and Environmental Engineering, University of Technology Sydney, Ultimo, NSW 2007, AustraliaDepartment of Geotechnical Engineering, Tongji University, Shanghai, 200092, China; Corresponding author.School of Civil and Environmental Engineering, University of Technology Sydney, Ultimo, NSW 2007, AustraliaA series of suction-controlled triaxial tests was conducted on Nanyang expansive clay to investigate the effects of dry density and suction on dilatancy and strength. The suction of the soil samples was controlled using a vapour equilibrium technique, with four suction levels ranging from 3.29 MPa to 198.14 MPa, where water retention is dominated by adsorption. The experimental results show that the tested soil exhibits a brittle failure mode under high suction, significantly distinguishing the hydro-mechanical behaviour of the soil at high suction from that observed at low suction. This brittle failure mode significantly increases the contribution of suction to peak strength compared to residual strength, causes the soil to fail before reaching the critical state, a phenomenon not observed in soils under high suction, and results in dilatancy caused by damage to the soil particle aggregates rather than particle rearrangement. The dilatancy data obtained from the triaxial tests reveal that significant soil dilatancy occurs during shear after reaching peak strength, with the maximum dilatancy angle increasing with suction and decreasing with confining pressure. However, the initial dry density has a negligible impact on the soil's dilatancy under high suction levels. This observation further supports that, for unsaturated soils under high suction levels, dilatancy is attributed to damage to soil particle aggregates rather than the rearrangement of soil particles.http://www.sciencedirect.com/science/article/pii/S1674775524004979DilatancyCritical stateShear strengthUnsaturated soil |
| spellingShingle | Ke Chen Xuzhen He Fayun Liang Daichao Sheng Strength and dilatancy of an unsaturated expansive soil at high suction levels Journal of Rock Mechanics and Geotechnical Engineering Dilatancy Critical state Shear strength Unsaturated soil |
| title | Strength and dilatancy of an unsaturated expansive soil at high suction levels |
| title_full | Strength and dilatancy of an unsaturated expansive soil at high suction levels |
| title_fullStr | Strength and dilatancy of an unsaturated expansive soil at high suction levels |
| title_full_unstemmed | Strength and dilatancy of an unsaturated expansive soil at high suction levels |
| title_short | Strength and dilatancy of an unsaturated expansive soil at high suction levels |
| title_sort | strength and dilatancy of an unsaturated expansive soil at high suction levels |
| topic | Dilatancy Critical state Shear strength Unsaturated soil |
| url | http://www.sciencedirect.com/science/article/pii/S1674775524004979 |
| work_keys_str_mv | AT kechen strengthanddilatancyofanunsaturatedexpansivesoilathighsuctionlevels AT xuzhenhe strengthanddilatancyofanunsaturatedexpansivesoilathighsuctionlevels AT fayunliang strengthanddilatancyofanunsaturatedexpansivesoilathighsuctionlevels AT daichaosheng strengthanddilatancyofanunsaturatedexpansivesoilathighsuctionlevels |