RHEOLOGY OF BITUMEN-RUBBER A COMPARATIVE STUDY OF TWO BINDERS AND TWO BINDER/FILLER SYSTEMS

摘要

Bitumen-Rubber has been in use for over 20 years in Southern Africa. In many cases practical experience has shown that Bitumen-Rubber performs superior to conventional penetration grade bitumen in surface treatments and asphalt surfacings. A limited study of the rheological properties of Bitumen-Rubber and penetration grade bitumen is described in this paper. This research forms part of a bigger effort to relate the behaviour of components of asphalt mixes to the overall performance of these mixes. The results of two binders and two binder/filler systems are reported. The binders studied are: conventional 60/70 penetration grade bitumen; and Bitumen-Rubber. The filler/binder ratio was 1,1 by mass for both binders. Some conclusions drawn based on this research include: 1. Rubber addition results in improved binder performance compared to conventional binder, especially when the binder is subjected to loading that simulates rutting mechanisms in asphalt 2. Filler addition to binder results in a stiffer mastic, but the general form of the Black Diagrams and Master Curves remain unchanged - this is true for both the conventional binder and the bitumen-rubber (for the filler investigated).