Evaluation of Rubberized Bitumen as Pavement Material
| dc.contributor.advisor | Alene, Alemgena (PhD) | |
| dc.contributor.author | Admas, Atnafu | |
| dc.date.accessioned | 2018-07-18T06:58:29Z | |
| dc.date.accessioned | 2023-11-11T12:53:47Z | |
| dc.date.available | 2018-07-18T06:58:29Z | |
| dc.date.available | 2023-11-11T12:53:47Z | |
| dc.date.issued | 2017-03 | |
| dc.description.abstract | Engineers especially in developed countries have been using modified binders to improve the performance of flexible pavements. They use different modifiers to enhance the rheological properties of asphalt binder. And specification is done by applying superpave binder grading system which requires performance based binder tests. In Ethiopia while one of the major pavement distresses is rutting, there is no significant effort to minimize this high temperature distress by using modified binder of improved visco-elastic property, more over the binder grading system does not comprise performance based tests. Therefore, the objective of this thesis is to evaluate the high temperature performance of asphalt binder modified with Reacted and Activated Rubber (RAR). i.e., to examine the contribution of this modified binder to minimize rutting. RAR commonly contains 62% Crumb Rubber, 22% soft bitumen, and 16% Activated Mineral Binder Stabilizer (AMBS). Using this modifier laboratory produced samples of 15, 20 and 25 percent RAR by mass of total binder were prepared. The control material was 80/100 penetration grade neat bitumen. To evaluate the visco-elastic properties of these modified samples different Dynamic Shear Rheometer (DSR) tests were carried out. The major DSR tests were Amplitude sweep test (AST), frequency sweep test (FST) and Multiple Stress Creep Recovery (MSCR). Also Performance Grade (PG) determinations at high temperatures were conducted. From the amplitude sweep test the linear visco elastic range was found to be 2%. Then to be well within visco-elastic region 1% strain was used to conduct frequency sweep test. Master curves developed from frequency sweep test showed that the modifier improves the shear modulus at high temperature and low frequency. The performance grade determination also depicted the improvement in PG as content of modifier increases. Even though the non-recoverable creep compliance improves as modifier increases, it is found that 25% replacement was not convenient in its percent recovery. Therefore the evaluation showed that the 20% modified binder is better in its rutting performance with improved performance grade. | en_US |
| dc.identifier.uri | http://etd.aau.edu.et/handle/12345678/9134 | |
| dc.language.iso | en | en_US |
| dc.subject | Road and Transport Engineering | en_US |
| dc.title | Evaluation of Rubberized Bitumen as Pavement Material | en_US |
| dc.type | Thesis | en_US |