Using Nanopolyacrylate and Nanocomposite as Binder Modifiers for Stone Mastic Asphalt (SMA)

Abstract

This paper presents the potential benefits of using nanopolyacrylate (NP) and nanocomposite (NC) polymers as modified binders in SMA mixtures. The optimum binder content of the SMA control mix was designed using PG76 binder and Modified Lottman test (AASHTO T283) was used to determine the stripping performance. A total of six (6) SMA modified mix were prepared using NP and NC modified binder formulations at 2%, 4% and 6%. Results from tensile strength test showed that SMA-NC6 have the highest IDT (521kPa) followed by SMA-NP6 (511 kPa), SMA-Control (500 kPa), SMA-NC4 (449kPa), SMA-NC2 (403kPa) and SMA-NP2 (379kPa). The stripping test on both control and modified SMA mixtures showed that TSR values for all the mix pass the 80 percent limit which fulfils the AASTHO T283 standard requirement and are therefore least susceptible to stripping. Based on the tensile strength test results and stripping performance, it was found that the addition of NC and NP modified binder demonstrate great potential in SMA mixtures showing significantly improved cohesion as well as adhesion properties of the binder. The results from this study found that all the SMA mix are resistance to moisture damage which could sustain the load from vehicles and exposed to severe condition without large degradation of the structure.