Comparative analysis of mechanical behavior of composite modified asphalt mixture based on PG technology

Each different kind of asphalt has its own PG classification, and different temperature classifications of asphalt can be applied to different regions. However, the commonly used 90# asphalt and SBS modified 90# asphalt do not meet the temperature difference requirements of different regions. In order to study the asphalt mixtures that are used in regions with different temperatures, this project uses styrene–butadienestyrene (SBS), styrene butadiene rubber (SBR), rubber powder, and thermo plastic styrene (TPS) with a composite modification of 90# asphalt and 110# asphalt. This study compares the road performance of the different composite modified asphalt mixture. The optimum amount of modifier for the composite modified asphalt specimens was obtained by means of an asphalt penetration test, a ductility test, a softening point test, and a viscosity test. The results show that the high and low temperature performance of the composite modified asphalt specimen is better than that of the single modified asphalt specimen. In terms of the comparison between 90# asphalt and 110# asphalt, 110# asphalt has better low temperature performance, while 90# asphalt has better high temperature performance; the water stability is not significantly different. Among the six composite modified asphalt mixtures that were tested, the SBS/rubber composite modified 110# asphalt mixture has the best road performance, especially with respect to high temperature performance. This paper provides some advice about asphalt materials selected from different regions based on PG technology。The research results have theoretical and practical value for improving the mechanical performance of asphalt pavement in different regions.