Characterization of Visco-Elastic Properties of Locally Available Asphalts in Pakistan

M. A. Javid, A. Rahim


Asphalt is a visco-elastic material having properties of elastic solid at low temperature and viscous liquid at high temperature. Properties of asphalt binder depend upon temperature, rate of loading and aging conditions. Although asphalt binder is only 4-5 % of asphalt concrete mix by weight but it plays a vital role in defining the pavement performance. That is, pavement response is heavily dependent upon the viscous and elastic properties of asphalt. In this research six asphalt samples were obtained from Attock and Karachi oil refinery and Dynamic Shear Rheometer was used in the laboratory to evaluate their viscous and elastic properties. Witczak predictive model was used to predict the binder viscosity and phase angle by using complex shear modulus and viscosity temperature susceptibility. The study revealed that Karachi virgin asphalt grades are more elastic as compared to Attock virgin asphalt grades both at low and high temperature. Similarly Attock PMB is more stiff and elastic as compared to Karachi 40/50, 60/70, and Attock 60/70. The research also revealed that Attock PMB has lesser temperature susceptibility as compared to virgin grades which makes it more suitable to resist rutting and cracking in extreme climatic conditions of Pakistan.

Full Text:



AASHTO M 320; Standard Specification for Performance-Graded Asphalt Binder, (1994), FHWA-SA-94-068.

AASHTO TP51 ; Standard Test Method for Determining the Rheological Properties of Asphalt Binder Using Dynamic Shear Rheometer, (1994), FHWA-SA-94-068.

D. A. Anderson, D. W. Christensen, H. U. Bahia, R. Dongre, M. G. Sharma, C. E. Antle, and C. E .J. Button; Binder Characterization and evaluation, Vol. III, Physical Characterization, and Strategic Highway Research Program report, SHRP A-369, (1994), Washington, D.C.

Javed Bari and M. W. Witczak; New Predictive Models for the viscosity and complex shear modulus of asphalt binders for use with the Mechanistic Emirical Pavement Design Guide, Transportation Research Board 2007 Annual Meeting CD-ROM.

F. L. Roberts, P. S. Kandahal and E. R. Brown; Hot Mix Asphalt Materials, Mixture Design, and Construction, 2nd Edition, Lanham Maryland: NAPA Education Foundation, (1996).

SUPERPAVE Asphalt Mixture Design; Lecture Notes, National Asphalt Training Center, Demonstration Project 101, Federal Highway Administration Office of Technology Applications, Washington D.C, (1994).

Waheed Uddin; Visco-elastic Characterization of Polymer Modified Asphalt Binders of Pavement Applications, the University of Mississippi, USA, Vol 13. Applied Rheology, (2003).

Copyright (c) 2016 M. A. Javid

Powered By KICS