SMA Anti-Crack Performance at Low Temperatures

The study of SMA mixture construction temperature is very important, because the required construction temperature of SMA mixtures is higher than that of average mixtures, which is easily conducive to asphalt aging during construction. Asphalt aging is one of the important factors that will have a great impact on SMA low-temperature performance. Curvature strain indicators of asphalt mixture can be got by low-temperature curvature tests and can be used to evaluate asphalt mixture performance. Failure energy resulting in damages is a comprehensive reflection of asphalt mixture strength and strain. Therefore, it is more advisable to evaluate low-temperature SMA anti-crack performance by referring to its unit failure energy. This paper presents the research on the relationship between different mixing temperatures of asphalt mixtures and their curvature strain indicators and the relationship between mixing temperatures and unit failure energy. The research proves that the higher these indicators are, the better anti-crack performance asphalt mixtures will have at low temperatures. At last, this paper concludes required construction temperature of SMA 90#.