Jordan Journal of Civil Engineering

The Effects of Moisture Susceptibility and Ageing Conditions on Engineering Properties of Nanosilica-Polymer- Modified Asphalt Blended with High RAP Contents


Nur Izzi Md. Yusoff; Ahmad Nazrul Hakimi Ibrahim; Amr Abdulrahman Aziz Salah; Faridah Hanim Khairuddin; Abdul Wahid Mohammed Salah;


The effects of mixing nanosilica with recycled asphalt pavement (RAP) on the properties of asphalt mixtures with different ageing and moisture susceptibility conditions were investigated. A polymer-modified asphalt (PMA), PG76, was mixed with varying percentages of nanosilica; namely, 0, 2, 4 and 6% by weight of asphalt and 50% RAP by weight of aggregate. Results showed that mixing nanosilica/PMA with 50% RAP improved the characteristics of resilient modulus and dynamic modulus under unaged, short-term ageing and long-term ageing conditions under both dry and wet conditions. The values for indirect tensile strength, resilient modulus and dynamic modulus tests under dry and long-term conditions are higher compared to the values for samples under wet and unaged condition; these values increased when the percentage of nanosilica was increased. The addition of 50% RAP to 6% nanosilica (6%NS/PMA + 50%RAP) was found to be the best combination in improving the performance characteristics of PMA under various conditions.


Nanosilica, Recycled asphalt pavement, Dynamic modulus, Indirect tensile strength, Resilient modulu.