Performance and Mechanism of High-Viscosity and High-Elasticity Bitumen (HVE-MB) Modified with Five Additives

In order to improve the viscoelasticity of bitumen, several modifiers were compounded with it, including SBS, reclaimed rubber powder, tackifier, plasticizer, and oil stabilizer, to produce High-viscosity and High-elastic Modified Bitumen (HVE-MB). The viscoelasticity and various physical and rheological properties of the bitumen were evaluated using a number of factors, such as dynamic viscosity at 60 °C, elastic recovery, penetration, softening point, ductility, and DSR. By comparing different types of modifiers and the content of SBS, it was found that the viscoelasticity of the original bitumen was significantly improved by adding the modifiers. In comparison to the original bitumen, the dynamic viscosity of the HVE-MB increased by more than 110 times, the elastic recovery rate more than doubled, the softening point and ductility improved, and the penetration decreased. As the content of SBS increased, the improvement in the properties became more significant. The workability of HVE-MB satisfies the requirement of less than 2.5 °C by adding the suitable dosage of stabilizer. On the other hand, the content of SBS can be adjusted based on the specific requirements. It is a sustainable and economic way to use the reclaimed rubber powder to improve the technical performance of bitumen.