Rice husk, in large quantities, is released to the environment due to rice production in Vietnam. If this material can be utilized, it can solve not only the economic issues but also the environmental problems and sustainable development of the country. Laboratory evaluation of asphalt mixture using Nano silica made from rice husk to improve rutting resistance of asphalt mixtures was presented in this study. A 60/70 bitumen was used as control asphalt binder. The ratio of Nano SIO2 used in this study was 0.3%, 0,6%, 0,9%, 1,2%, and 1,5% by weight of powder. A dense gradation with nominal maximum aggregate size of 12.5mm was used for the asphalt mixtures. Marshall stability (MS) test and wheel tracking (WT) test were conducted to evaluate the rutting resistance of asphalt mixtures. It was found that the asphalt mixtures using 0.5%, 1.0%, and 1.5% Nano SIO2 have the rut depths of 5.35mm, 5.39mm, and 5.45mm, respectively, which is 30%, 31% and 29% lower than the control asphalt mixtures at 15,000 load cycles. Moreover, the static modulus of asphalt mixtures using 0.9% Nano SIO2 at 60oC is higher than the control mixtures. Based on the results of this study, it can be concluded that the addition of Nano SIO2 into asphalt mixtures can enhance the rutting performance of asphalt concrete under high temperatures significantly. It is noted that these conclusions were based on only on a limited number of samples and conditions. Further studies must be conducted to investigate the effect of Nano SIO2 on fatigue cracking and moisture damage of asphalt pavement in the field.

• Van Bach Le(Department of Civil Engineering, University of Transport and Communications)
• Van Phuc Le(Department of Civil Engineering, University of Transport and Communications)
• Dong Nguyen(Department of Civil Engineering, University of Transport and Communications)