丁苯橡胶含量对改性沥青高低温性能影响的研究

Study on influence of SBR dosage on high and low temperature performance of modified asphalt

以不同含量丁苯橡胶(SBR)改性剂制备改性沥青,采用常规指标评价和动态力学分析(DMA)两种方法,考察SBR含量对改性沥青高低温性能的影响。结果表明:随着SBR改性剂含量的增加,改性沥青的低温延度增大,软化点稍有升高;改性沥青的弹性模量和黏性模量均随着SBR改性剂含量的增加而变大,SBR改性剂含量不宜过高或者过低,含量过低,SBR黏弹性不能充分发挥,含量过高,改性沥青产生相分离,Cole-Cole图可以作为评判改性沥青相容性好坏的重要依据;改性沥青的劲度模量和蠕变率随SBR改性剂含量的增加而变大,低温性能变好。

The modified asphalts were prepared with different dosages of SBR modifiers and the influence of SBR dosages on the high and low temperature performance of asphalts were investigated by conventional index assessment and dynamic mechanical analysis ( DMA). The results showed that the low-temperature ductility of the modified asphalts in creased and the softening point rised slightly with the increase of SBR content. The elastic modulus and viscous modulus increased with the rise of SBR dosages.The content of SBR modifiers should not be too high or too low, the viscoelasticity of SBR can not be fully exerted if the dosage was too low and phase separation appeared if the dosage was too high. The cole-cole diagram can be used as an important basis for evaluating the compatibility of modified asphalt.The stiffness modulus and creep rate of the modified asphalts became larger with the increase of the modifier content.which meaned the low-temperature performance got better.