Laboratory Investigation on the Effect of Warm Mixing Agent on Low Temperature Performance of Base Asphalt

Abstract

The properties of asphalt materials have a significant impact on the quality and performance of road surfaces. Asphalt materials are the main factor affecting low-temperature cracking of road surfaces. The low-temperature performance of asphalt and asphalt mixtures has a significant impact on the quality and service life of road surfaces in northern and central China. SHRP research results suggest that asphalt contributes 80% to the cracking resistance of asphalt pavement. Low temperature cracking is one of the main diseases of asphalt pavement, which is more common in northern China, especially in cold regions and areas with significant daily temperature fluctuations. Cracks will bring many accompanying diseases, such as looseness, erosion, and potholes. At present, the focus is still on considering high-temperature performance indicators, and there is still insufficient consideration for low-temperature cracking of roads in cold regions of China at the asphalt level. There are still serious deficiencies in the evaluation methods and selection of asphalt and asphalt mixtures in low-temperature areas, with a large number of modified asphalt not being evaluated. There is still a blind spot in the understanding of various influencing factors of low-temperature performance (such as type of modifier, Content of modifier, additives, etc.), resulting in problems in engineering application and higher maintenance costs in the later stage. This study mainly used BBR experiments to study different modified asphalt binders, focusing on the base asphalt and studying the influence of warm mix agents Sasobit and SNJ on the low-temperature performance and other properties of asphalt. Finally, based on the low-temperature performance of each modified asphalt, conduct an overall evaluation and comparison, and provide recommendations for the design of asphalt pavement materials.