Needed Characterization of Modified Binders in India
S. Anjan Kumar, Department of Civil Engineering, and A.Veeraragavan, Professor of Civil Engineering, Indian Institute of Technology, Chennai.

The thermo mechanical properties of bituminous binder have a major effect on its subsequent in-service performance. The rheology of conventional binders is relatively simple and behavior can be predicted through the use of traditional tests such as penetration, softening point and viscosity testing at various temperatures. On the other hand the rheology of modified binders is highly complex and, although the results from traditional tests may indicate a significant improvement in properties, the in-service performance of these binders is not easily categorized. This paper presents detailed investigations on the physical properties of modified binders in comparison with conventional binder using current Indian specifications. Firstly, it gives a brief description on modification of bitumen its advantages and limitations. It also looks into the present specifications that are followed in India and the need for improved specifications for performance based binder characterization, which may provide fundamental explanations with respect to in-service performance.