Volume 46, N. 1

January-March 2023

Durability and mechanical long-term performance of reclaimed asphalt pavement stabilized by alkali-activation

Article

Volume 46, N. 1, January-March 2023 | DOWNLOAD PDF (41 downloads)

Abstract

The application of alkali-activated industrial by-products for the stabilization of reclaimed asphalt pavement (RAP), can become a sustainable solution to reduce the carbon footprint of road construction and maintenance activities. Furthermore, this approach can also reduce the increasing depletion of natural resources. Thus, the durability and long-term mechanical performance of RAP stabilized with alkali-activated fly ash were assessed in this study. The alkaline activator was a solution composed of sodium hydroxide and sodium silicate. To this extent, unconfined compressive strength (UCS) and durability tests were conducted in this research. The proposed alkali-activated binder significantly increased the UCS of RAP mixtures, with long-term (365 days) results reaching values up to 32 MPa; fulfilling the strength requirements for cement-stabilized soil mixtures and even stable inorganic binder materials for road base and sub-base layers of pavements. These results indicate that when stabilized with an alkali-activated fly ash binder, RAP presents several applications for road engineering; even when subjected to seasonal variations in humidity and temperature, as shown by the durability tests.

Keywords: Reclaimed asphalt pavement, Fly ash, Alkali activated binder, Durability, Long-term performance,


Submitted on July 02, 2022.
Final Acceptance on October 21, 2022.
Discussion open until May 31, 2023.
DOI: 10.28927/SR.2023.007422