An Investigation of Instability on Constant Shear Drained (CSD) Path under the CSSM Framework: A DEM Study
Soil liquefaction or instability, one of the most catastrophic phenomena, has attracted significant research attention in recent years. The main cause of soil liquefaction or instability is the reduction in the effective stress in the soil due to the build-up of pore water pressure. Such a phenomeno...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2022-12-01
|
| Series: | Geosciences |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2076-3263/12/12/449 |
| _version_ | 1797457660001386496 |
|---|---|
| author | Hoang Bao Khoi Nguyen Md Mizanur Rahman Md Rajibul Karim |
| author_facet | Hoang Bao Khoi Nguyen Md Mizanur Rahman Md Rajibul Karim |
| author_sort | Hoang Bao Khoi Nguyen |
| collection | DOAJ |
| description | Soil liquefaction or instability, one of the most catastrophic phenomena, has attracted significant research attention in recent years. The main cause of soil liquefaction or instability is the reduction in the effective stress in the soil due to the build-up of pore water pressure. Such a phenomenon has often been thought to be related to the undrained shearing of saturated or nearly saturated sandy soils. Notwithstanding, many researchers also reported soil instability under a drained condition due to the reduction in lateral stress. This condition is often referred to as the constant shear drained (CSD) condition, and it is not uncommon in nature, especially in a soil slope. Even though several catastrophic dam failures have been attributed to CSD failure, the failure mechanisms in CSD conditions are not well understood, e.g., how the volumetric strain or effective stress changes at the triggering of flow deformation. Researchers often consider the soil fabric to be one of the contributors to soil behaviour and use this parameter to explain the failure mechanism of soil. However, the soil fabric is difficult to measure in conventional laboratory tests. Due to that reason, a numerical approach capable of capturing the soil fabric, the discrete element method (DEM), is used to investigate the CSD shearing mechanism. A series of simulations on 3D assemblies of ellipsoid particles was conducted. The DEM specimens exhibited instability behaviour when the effective stress paths nearly reached the critical state line. It can be clearly observed that the axial and volumetric strains changed suddenly when the stress states were close to the critical state line. Alongside these micromechanical observations, the study also presents deeper insights into soil behaviour by relating the macro-observations to the micromechanical aspect of the soil. |
| first_indexed | 2024-03-09T16:26:12Z |
| format | Article |
| id | doaj.art-0e6c4ff240b24573bd77b59e5c59e102 |
| institution | Directory Open Access Journal |
| issn | 2076-3263 |
| language | English |
| last_indexed | 2024-03-09T16:26:12Z |
| publishDate | 2022-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Geosciences |
| spelling | doaj.art-0e6c4ff240b24573bd77b59e5c59e1022023-11-24T15:07:16ZengMDPI AGGeosciences2076-32632022-12-01121244910.3390/geosciences12120449An Investigation of Instability on Constant Shear Drained (CSD) Path under the CSSM Framework: A DEM StudyHoang Bao Khoi Nguyen0Md Mizanur Rahman1Md Rajibul Karim2UniSA STEM, University of South Australia, Adelaide, SA 5095, AustraliaUniSA STEM, University of South Australia, Adelaide, SA 5095, AustraliaUniSA STEM, University of South Australia, Adelaide, SA 5095, AustraliaSoil liquefaction or instability, one of the most catastrophic phenomena, has attracted significant research attention in recent years. The main cause of soil liquefaction or instability is the reduction in the effective stress in the soil due to the build-up of pore water pressure. Such a phenomenon has often been thought to be related to the undrained shearing of saturated or nearly saturated sandy soils. Notwithstanding, many researchers also reported soil instability under a drained condition due to the reduction in lateral stress. This condition is often referred to as the constant shear drained (CSD) condition, and it is not uncommon in nature, especially in a soil slope. Even though several catastrophic dam failures have been attributed to CSD failure, the failure mechanisms in CSD conditions are not well understood, e.g., how the volumetric strain or effective stress changes at the triggering of flow deformation. Researchers often consider the soil fabric to be one of the contributors to soil behaviour and use this parameter to explain the failure mechanism of soil. However, the soil fabric is difficult to measure in conventional laboratory tests. Due to that reason, a numerical approach capable of capturing the soil fabric, the discrete element method (DEM), is used to investigate the CSD shearing mechanism. A series of simulations on 3D assemblies of ellipsoid particles was conducted. The DEM specimens exhibited instability behaviour when the effective stress paths nearly reached the critical state line. It can be clearly observed that the axial and volumetric strains changed suddenly when the stress states were close to the critical state line. Alongside these micromechanical observations, the study also presents deeper insights into soil behaviour by relating the macro-observations to the micromechanical aspect of the soil.https://www.mdpi.com/2076-3263/12/12/449soil liquefactionconstant shear drained testcritical state |
| spellingShingle | Hoang Bao Khoi Nguyen Md Mizanur Rahman Md Rajibul Karim An Investigation of Instability on Constant Shear Drained (CSD) Path under the CSSM Framework: A DEM Study Geosciences soil liquefaction constant shear drained test critical state |
| title | An Investigation of Instability on Constant Shear Drained (CSD) Path under the CSSM Framework: A DEM Study |
| title_full | An Investigation of Instability on Constant Shear Drained (CSD) Path under the CSSM Framework: A DEM Study |
| title_fullStr | An Investigation of Instability on Constant Shear Drained (CSD) Path under the CSSM Framework: A DEM Study |
| title_full_unstemmed | An Investigation of Instability on Constant Shear Drained (CSD) Path under the CSSM Framework: A DEM Study |
| title_short | An Investigation of Instability on Constant Shear Drained (CSD) Path under the CSSM Framework: A DEM Study |
| title_sort | investigation of instability on constant shear drained csd path under the cssm framework a dem study |
| topic | soil liquefaction constant shear drained test critical state |
| url | https://www.mdpi.com/2076-3263/12/12/449 |
| work_keys_str_mv | AT hoangbaokhoinguyen aninvestigationofinstabilityonconstantsheardrainedcsdpathunderthecssmframeworkademstudy AT mdmizanurrahman aninvestigationofinstabilityonconstantsheardrainedcsdpathunderthecssmframeworkademstudy AT mdrajibulkarim aninvestigationofinstabilityonconstantsheardrainedcsdpathunderthecssmframeworkademstudy AT hoangbaokhoinguyen investigationofinstabilityonconstantsheardrainedcsdpathunderthecssmframeworkademstudy AT mdmizanurrahman investigationofinstabilityonconstantsheardrainedcsdpathunderthecssmframeworkademstudy AT mdrajibulkarim investigationofinstabilityonconstantsheardrainedcsdpathunderthecssmframeworkademstudy |