Preparation and properties of a novel high-viscosity modified bitumen

To develop a high-performance binder for open-graded porous asphalt mixtures, a novel high-viscosity modified bitumen (N-HVA) was prepared by melt blending base bitumen, terpene-styrene resin (TSR), styr-ene-butadienestyrene block copolymer (SBS), compatibilizer, and stabilizer, the optimal dosage of each modifier was determined. Properties and microstructure of the N-HVA were explored. Two commercially high-viscosity modified bitumens, TPS-HVA and SINOTPS-HVA, were adopted for comparison. The test results show that the appropriate dosage of modifiers is 7 wt% SBS, 4 wt% TSR, 3 wt% compatibilizer, and 0.2 wt% stabilizer. N-HVA shows improved rutting resistance, anti-aging ability, low-temperature flexibility, and meets the storage stability requirements. It demonstrated a more balanced performance than SINOTPS-HVA and TPS-HVA. During the preparation of N-HVA, the addition of the modifier inhibits the phase transition of the bitumen and raises the thermal stability of the composite system. In addition, the composite modifier possesses excellent compatibility with the base bitumen. The modification process is mainly based on physical blending, accompanied by chemical reactions..