Hot mix asphalt (HMA) is a mixture containing aggregates and asphalt binders prepared at specified proportions. The aggregates and asphalt binder proportions are determined through a mix design procedure such as the Marshall Mix Design or the Superpave Mix Design methods.
The main objectives of this study are:
- Develop a procedure by which WMA-FA mixtures can be produced in the laboratory;
- Evaluate the performance of WMA-FA mixtures with regard to moisture susceptibility and permanent deformation;
- Evaluate the performance of control HMA mixtures prepared using the same aggregates and asphalt binders;
- Compare the performance of WMA-FA and HMA mixtures; and
- Recommend changes to current ODOT practices and specifications to address the research findings.
Based on the research findings, WMA-FA seems to be a viable alternative to HMA as a paving material for roadways subjected to traffic levels ranging from low to medium. However, the performance of such material has to be evaluated in terms of permanent deformation. Therefore, it is recommended to modify ODOT C&MS Item 441 to include a permanent deformation test as part of the mix design procedure to ensure satisfactory field performance.