基于时间和温度依赖性的SBS/ 多聚磷酸复合改性沥青流变性能研究

为分析多聚磷酸掺量对SBS/多聚磷酸复合改性沥青高温流变特性的影响,对比复合改性沥青与基质沥青、SBS改性沥青流变特性的差异,本文采用SK90号基质沥青、制备4.5%SBS改性沥青以及SBS/多聚磷酸复合改性沥青。对沥青试样进行60℃频率扫描和30℃-60℃温度扫描试验,分析沥青结合料复数模量、相位角随加载频率和温度的变化规律。结果表明:SBS改性沥青、SBS/多聚磷酸复合改性沥青的复数模量值远大于基质沥青,SBS/多聚磷酸复合改性沥青的复数模量随着多聚磷酸掺量的增多而增大;SBS改性沥青和SBS/多聚磷酸复合改性沥青的相位角随荷载作用频率上升而迅速增大;SBS改性沥青和SBS/多聚磷酸复合改性沥青的温度敏感性较基质沥青有了显著的改;3.5%SBS+1.6%PPA复合改性沥青的复数剪切模量大于改性剂掺量为4.5%的SBS改性沥青。

Rheological properties of SBS/polyphosphoric acid modified asphalt based on time and temperature dependence

To analyze the effect of polyphosphoric acid content on the high temperature rheological properties of SBS/ polyphosphoric acid modified asphalt and compare the rheological properties difference between asphalt bitumen and SBS modified asphalt, SK90 asphalt, 4.5%SBS modified asphalt and SBS/polyphosphoric acid modified asphalt were prepared.Then frequency sweep and temperature sweep was applied to obtain the complex modulus and phase angle of asphalt.The results showed that the complex modulus of SBS modified asphalt and SBS/polyphosphoric acid asphalt was much greater than that of asphalt bitumen.The complex modulus of SBS/polyphosphoric acid composite asphalt increased with the increase of polyphosphoric acid content, phase angle of SBS modified asphalt and SBS/polyphosphoric acid modified asphalt increases with the loading frequency.The temperature sensitivity of SBS modified asphalt and SBS/polyphosphoric acid modified bitumen has been significantly improved than that of asphalt bitumen.The complex modulus of 3.5%SBS+1.6%PPA modified asphalt is greater than that of SBS modified asphalt with 4.5% SBS modifier.