为研究短期老化作用、温度分别对3种聚合物改性沥青:SBS改性沥青(SMA)、橡胶粉改性沥青(RPMA)、复合改性沥青(CMA)抗变形能力的影响,利用动态剪切流变仪(DSR)分别对3种沥青原样及旋转薄膜烘箱老化(RTFOT)后的沥青试样进行重复蠕变恢复实验,利用抗变形指数HL与蠕变劲度的粘性部分GV 对沥青高温变形性能进行评价;并利用扫描电子显微镜对各沥青试样的微观结构形态进行观察,从微观角度解释不同沥青抗变形能力存在差异的原因.结果表明,GV 与HL可较好地评价高温下改性沥青的抗变形能力;短期老化作用使基质沥青与改性剂的微观结构发生变化,抗变形性能改变;温度对沥青抗变形能力的影响取决于沥青温度敏感性的强弱,RPMA在高温状态下表现最好.
In order to investigate the effect of short-term aging (film oven aging)and temperature on anti-de-formation of different kinds of asphalt including SBS modified asphalt (SMA),rubber powder modified asphalt (RPMA)and composite modified asphalt (CMA),repeat creep recovery test was conducted by the dynamic shear rheometer(DSR),the anti-deformation index-HL(calculated by complex shear modulus-G?)and viscous part of complex shear modulus-GV was used to evaluate the anti-deformation of these kinds of asphalt respec-tively.In addition,scanning electron microscope (SEM)was used to observe the microstructures of these kinds of asphalt,the reasons why there are different performances among them about anti-deformation were explained from microscopic view.Results show that:GV and HL can evaluate the anti-deformation of modified asphalt under high temperature properly;the microstructure of matrix asphalt and modifier were changed after short-term aging,so their anti-deformation changed;the influence of temperature on anti-deformation of modified as-phalt depends on the temperature sensitivity of asphalt,RPMA has the best anti-deformation under high tem-perature.