老化沥青介入下SBS改性沥青特性研究

Performance Characteristics of SBS Modified Asphalt with Aging Asphalt

目的通过分析不同老化沥青掺量(0%、10%、20%、30%)的再生沥青的温度敏感性、高低温性能、蠕变疲劳性能和微观分析等,系统地研究老化沥青介入下SBS改性沥青的特性.方法对不同沥青的动力黏度、黏温指数(VTS)进行测定和分析;采用高温动态剪切流变仪、弯曲梁流变仪、直接拉伸仪对样品试验,利用荧光显微镜分析了沥青样品成分.结果在高低温下,再生沥青的黏度变化不一致;当老化沥青掺量大于30%时,才能改善再生沥青的温度敏感性;随着老化沥青掺量的增加,再生SBS改性沥青具有更好的高温抗车辙性能,临界开裂温度温度则不断升高;老化沥青少量掺加有利于提高再生沥青的疲劳寿命,大量掺加会降低沥青的蠕变疲劳性能.结论随着老化沥青掺量的增加,再生SBS改性沥青具有更好的高温抗车辙性能,但再生沥青的低温开裂性降低,蠕变疲劳性能下降,SBS分布变得不均匀且粒径大小不一.

This paper provides a research on the temperature sensitivity,high and low temperature performance,creep fatigue properties and microscopic analysis of recycled asphalt with different aging asphalt content(0%,10%,20%,30%).The dynamic viscosity and viscosity-temperature index(VTS)of different asphalt were measured and analyzed.The samples were tested by high-temperature dynamic shear rheometer,bending beam rheometer and direct tensile tester.Finally,the composition of asphalt samples was analyzed by fluorescence microscope.At high and low temperature,the change of viscosity of recycled asphalt is inconsistent.When the content of aged asphalt is more than 30%,the temperature sensitivity of recycled asphalt can be improved.With the increase of the content of aged asphalt,the regenerated SBS modified asphalt has better high temperature Anti-rutting performance,the critical cracking temperature is rising;A small amount of aging asphalt is conducive to improving the fatigue life of recycled asphalt,a large number of mixing will reduce the creep fatigue properties of asphalt.With the increase of the content of aged bitumen,the regenerated SBS modified bitumen has better high temperature anti-rutting performance,but the reclaimed bitumen′s low temperature cracking resistance decreases,Creep fatigue performance decreases,SBS distribution becomes uneven and particle sizes are different.