Determining the effect of ageing of nano-clay modified bitumen using atomic force microscopy
نویسندگان
1 Department of Civil Engineering, University of Tripoli, Elhei Eljamaiei 1, Elhei Eljamaiei Main Street, Tripoli, Libya
2 School of Housing, Building and Planning, Universiti Sains Malaysia, Penang, Malaysia
3 Department of Civil and Environmental Engineering, Universiti Teknologi Petronas, Perak, Malaysia
4 Department of Civil and Environmental Engineering, Universiti Teknologi Petronas, Perak, Malaysia
5 Faculty of Engineering, Jazan University, Jazan 706, Kingdom of Saudi Arabia
6 Department of Civil and Environmental Engineering, Universiti Teknologi Petronas, Perak, Malaysia
7 Department of Civil and Environmental Engineering, Universiti Teknologi Petronas, Perak, Malaysia
8 Department of Civil Engineering, Universiti Kebangsaan Malaysia, Selangor, Malaysia
doi
10.24200/sci.2021.56224.4610چکیده
This study investigates the effects of ageing simulation on the physical properties of nano-clay modified bitumens (NCMBs). Bitumen with penetration grade 60/70 is modified with 0, 2 and 4% nano-clay, and the consistency of the samples is characterized using the penetration, softening point, and viscosity tests before and after aging. Atomic force microscopy (AFM) is used to evaluate the surface roughness and tip deflection of the modified bitumens. The results of the consistency tests revealed that the incorporation of nano-clay up to 4% NC resulted in increased hardness of the modified bitumen, and all modified bitumens were affected by ageing; the results for surface roughness and tip deflection showed a similar trend and 2NCMB exhibited the lowest roughness and highest tip deflection. However, the results of consistency tests and AFM for ageing sensitivity of the bitumens are different, indicating that the addition of nano-clay has an effect on the modified bitumen but not on the unmodified bitumen. There is a high correlation between the results of consistency tests, surface roughness and tip deflection, which implies that AFM is able to identify any changes in the fluidity of the bitumen. However, the correlation between tip deflection and penetration is very weak.
