Discrete element modelling of idealised asphalt mixture
This thesis investigates the use of Discrete Element Modelling (DEM) to simulate the behaviour of a highly idealised bituminous mixture under uniaxial and triaxial compressive creep tests. The idealised mixture comprises single-sized spherical (sand-sized) particles mixed with bitumen and was chosen...
| Main Author: | |
|---|---|
| Format: | Thesis (University of Nottingham only) |
| Language: | English |
| Published: |
2006
|
| Subjects: | |
| Online Access: | https://eprints.nottingham.ac.uk/11720/ |
| _version_ | 1848791343424339968 |
|---|---|
| author | Lee, York Wei |
| author_facet | Lee, York Wei |
| author_sort | Lee, York Wei |
| building | Nottingham Research Data Repository |
| collection | Online Access |
| description | This thesis investigates the use of Discrete Element Modelling (DEM) to simulate the behaviour of a highly idealised bituminous mixture under uniaxial and triaxial compressive creep tests. The idealised mixture comprises single-sized spherical (sand-sized) particles mixed with bitumen and was chosen so that the packing characteristics are known (dense random packing) and the behaviour of the mixture will e dominated by the bitumen and complex aggregate interlock effects will be minimised. In this type of approach the effect of the bitumen is represented as shear and normal contact stiffnesses. A numerical sample preparation procedure has been developed to ensure that the final specimen is isotropic and has the correct volumetrics. Elastic contact properties have been used to investigate the effect of the shear and normal contact stiffnesses on bulk material properties. The bulk modulus was found to be linearly dependent on the normal contact stiffness and independent of the shear contact stiffness. Poisson's ratio was found to be dependent on only the ratio of the shear contact stiffness to the normal contact stiffness. An elastic contact has been assumed for the compressive normal contact stiffness and a viscoelastic contact for shear and tensile normal contact stiffness to represent the contact behaviour in idealised mixture. The idealised mixture is found to dilate when the ratio of compressive to tensile contact stiffness increases as a function of loading time. Uniaxial and triaxial viscoelastic simulations have been performed to investigate the effect of stress ratio on the rate of dilation with shear strain for the sand asphalt. The numerical results have been validated with experimental data. The geometric factors that influence asphalt dilation are investigated. The level of dilation was found to be dominated by the proportion of frictional contacts in the sample. Simulations have been performed to investigate the effect of particle shape on asphalt dilation. Greater dilation was found in the sample with clumps under loading. |
| first_indexed | 2025-11-14T18:27:00Z |
| format | Thesis (University of Nottingham only) |
| id | nottingham-11720 |
| institution | University of Nottingham Malaysia Campus |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-14T18:27:00Z |
| publishDate | 2006 |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | nottingham-117202025-02-28T11:15:13Z https://eprints.nottingham.ac.uk/11720/ Discrete element modelling of idealised asphalt mixture Lee, York Wei This thesis investigates the use of Discrete Element Modelling (DEM) to simulate the behaviour of a highly idealised bituminous mixture under uniaxial and triaxial compressive creep tests. The idealised mixture comprises single-sized spherical (sand-sized) particles mixed with bitumen and was chosen so that the packing characteristics are known (dense random packing) and the behaviour of the mixture will e dominated by the bitumen and complex aggregate interlock effects will be minimised. In this type of approach the effect of the bitumen is represented as shear and normal contact stiffnesses. A numerical sample preparation procedure has been developed to ensure that the final specimen is isotropic and has the correct volumetrics. Elastic contact properties have been used to investigate the effect of the shear and normal contact stiffnesses on bulk material properties. The bulk modulus was found to be linearly dependent on the normal contact stiffness and independent of the shear contact stiffness. Poisson's ratio was found to be dependent on only the ratio of the shear contact stiffness to the normal contact stiffness. An elastic contact has been assumed for the compressive normal contact stiffness and a viscoelastic contact for shear and tensile normal contact stiffness to represent the contact behaviour in idealised mixture. The idealised mixture is found to dilate when the ratio of compressive to tensile contact stiffness increases as a function of loading time. Uniaxial and triaxial viscoelastic simulations have been performed to investigate the effect of stress ratio on the rate of dilation with shear strain for the sand asphalt. The numerical results have been validated with experimental data. The geometric factors that influence asphalt dilation are investigated. The level of dilation was found to be dominated by the proportion of frictional contacts in the sample. Simulations have been performed to investigate the effect of particle shape on asphalt dilation. Greater dilation was found in the sample with clumps under loading. 2006-07-14 Thesis (University of Nottingham only) NonPeerReviewed application/pdf en arr https://eprints.nottingham.ac.uk/11720/1/430521.pdf Lee, York Wei (2006) Discrete element modelling of idealised asphalt mixture. PhD thesis, University of Nottingham. Discrete element modelling Bituminous materials Elastic contact properties Asphalt dilation |
| spellingShingle | Discrete element modelling Bituminous materials Elastic contact properties Asphalt dilation Lee, York Wei Discrete element modelling of idealised asphalt mixture |
| title | Discrete element modelling of idealised asphalt mixture |
| title_full | Discrete element modelling of idealised asphalt mixture |
| title_fullStr | Discrete element modelling of idealised asphalt mixture |
| title_full_unstemmed | Discrete element modelling of idealised asphalt mixture |
| title_short | Discrete element modelling of idealised asphalt mixture |
| title_sort | discrete element modelling of idealised asphalt mixture |
| topic | Discrete element modelling Bituminous materials Elastic contact properties Asphalt dilation |
| url | https://eprints.nottingham.ac.uk/11720/ |