Investigation the effects of warm mix additive on the bitumen and stone mastic asphalt pavement

The effort of constructing durable roads with higher standards has required to research the usage of various additives in bituminous coating so far. Nowadays polymer modification is effectively applied, and additives, which can provide better compaction and less expense by improving workability features are considered. . These additives contribute to performance as well as workability. In this study conventional and rheological properties of binders including stiren-butadien-stiren (SBS) and an organic warm mixture additive (Sasobit) in various rates and also the mechanical properties of Stone mastic asphalt prepared by these binders are investigated. The effects of additives, which are used separately and together in the binder are examined. In conclusion it was determined that SBS modification has better than Sasobit modification in terms of rutting parameter especially in high temperatures. Sasobit modification significantly decreased the viscosity and increased the softening point compared to SBS modification. It was also determined that Sasobit contribute to increase the flexibility of SBS modified bitumen in case the additives are used in the same binder together. The usage of 3% SBS with 3% Sasobit provide better performance with respect to mechanical properties.