Application of Nano Silica to Improve Self-Healing of Bitumen Mixtures

Rutting and cracking are two common modes of failure in asphalt pavements. Due to increase in traffic volume and traffic loads, asphalt pavements deteriorate gradually during their service life. Deterioration of asphalt pavements can be eliminated/minimized by enhancing the quality of bitumen with modified bitumen. The use of nano materials as an additive because of their special characteristics is one of the self healing techniques which has the potential to improve the pavement performance, extending its life span and also eliminating the need for pavement maintenance. This research work investigated the performance of nano silica in asphalt pavement. Experiments were conducted on bitumen and modified bitumen (addition of nano silica of different percentages, 2%, 4%, 6%, 8% and 10% with bitumen) in order to find the optimum nano silica content for preparing Marshal Mix. It was found that 6% of nano silica in modified bitumen gave improved properties compared to other percentages of nano silica contents that were examined. Nano silica modified bituminous mix (NSMBM) samples were prepared with various bitumen contents, i.e., 4.5%, 5% and 5.5%, and Marshal stability test was conducted. This study concludes that the results obtained from Marshal test give higher stability value (10.32 kN to 20.18 kN) and lesser flow value (4.48 mm to 2.60 mm) for modified bituminous mixes over unmodified bituminous mix samples. Finally, the healing index was also determined based on theoretical approach and obtained 80% healing rate for modified bituminous mix. Further investigations can be carried out on long term effects of nano silica in asphalt pavements as well as test rest periods for different temperatures and different loads.

Language

  • English

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 01759335
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Nov 23 2020 10:19AM