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| Author(s): |
Gustavo dos Santos Pinheiro
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Escola Politécnica (EP/BC) |
| Defense date: | 2021-04-19 |
| Examining board members: |
Kamilla Vasconcelos Savasini;
Verônica Teixeira Franco Castelo Branco;
Luciano Pivoto Specht
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| Advisor: | Kamilla Vasconcelos Savasini |
| Abstract | |
The incorporation of milled material in the production of recycled hot mix asphalts (HMA) represents an advance in the road sector and an incentive for more sustainable innovative techniques development. The use of reclaimed asphalt pavement (RAP), regarding economic, environmental and performance issues of the recycled material, seems to be an advantageous alternative for the restoration and construction of new roads. However, one of the obstacles to its use in new mixtures production is related to the inherent variability of RAP, manifested mainly due to the asphalt binder. Procedures that allow obtaining this aged binder are commonly used, such as extraction with solvents and recovery applying distillation techniques. However, such methods can change the asphalt binder\'s intrinsic properties, such as rheological and chemical characteristics, which may lead to flaws in the dosage of recycled HMA. Another point regarding the incorporation of RAP is that different levels of interaction (degree of blending, or DoB) tend to occur between the new asphalt binder and the RAP aged binder. Understanding this mechanism and how much of the aged RAP binder contributes to the final physical or rheological properties can help to obtain more consistent design methods. Thus, this study evaluated both asphalt binder extraction and recovery techniques from milled materials, and its effects on recycled asphalt mixtures. In addition, it was investigated the DoB from recycled HMAs. It can be concluded that: the processes of reduction and preparation of the samples before extraction have an influence on recovered binder rheological properties; the definition of the final binder type, from the mixture between virgin and aged RAP binders for the recycled HMA, shows dependency on the variations of parameter Tc, resulting from the same RAP; and, for the analysis of the asphalt binders interaction, the Black space diagram showed to be a good option to qualitatively assess rheological changes between the extraction stages and, also, the homogeneity conditions of asphalt binder recovered. (AU) | |
| FAPESP's process: | 19/08415-1 - Degree of blending on hot and warm asphalt recycling |
| Grantee: | Gustavo dos Santos Pinheiro |
| Support Opportunities: | Scholarships in Brazil - Master |