Modification of Bitumen for Improved Pavement Performance under Heavy Traffic Loading

Inadequate structural capacity, insufficient maintenance funds, ever increasing traffic volume and excessive overloading, particularly by commercial vehicles (mainly two axle trucks), have rendered existing pavement non-performing or poorly performing due to its inability to withstand excessive stresses and strains. This has necessitated the increased use of modified bitumen in surface courses like Bituminous Concrete. Towards this end, field trials were undertaken in India in 1995 to evaluate the performance of test sections laid with SBS modified bitumen. This paper presents an overview of the work done and highlights the broad features of experiments done in India with polymer modified bitumen(PMB).The paper also brings out distinct advantages of modified bitumen over the conventional bitumen and presents data on performance characteristics of the test tracks laid.