Evaluation on low temperature characteristics of SBS/CR modified asphalt binder under different aging conditions

摘要

This study discussed the low temperature performance of styrene-butadiene-styrene(SBS)/crumb rubber(CR)modified asphalt under different aging process.The bending beam rheometer(BBR)test was conducted to compare the low temperature performance of SBS and SBS/CR modified asphalt at three different temperatures.The continuous low service temperature of two modified asphalt binders was calculated based on the ASTM method.The simple fractional viscoelastic model was implemented to better describe the creep behaviour of asphalt at low temperatures from the BBR test results.The damping ratio and dissipated energy ratio were also derived from the simple fractional model to assess the low temperature performance of asphalt from the aspect of energy.The analysis results showed that adding CR to SBS modified asphalt was beneficial to reduce the low service temperature and increase the values of damping ratio and dissipated energy ratio before and after the aging process.It has been proved that the low temperature performance of SBS/CR modified asphalt is much better than that of SBS modified asphalt under different aging conditions.