基于氧化动态模型的沥青热氧老化性能预测

为研究沥青热氧老化过程中的动态变化规律，对3种沥青在不同时间和温度条件下进行热氧老化，采用动态流变剪切仪对各老化后的沥青试样进行动态频率扫描试验，得到沥青的复数剪切模量、相位角主曲线，进而获得各试样的交叉模量，分析交叉模量在沥青老化过程中随老化时间和老化温度的动态变化规律，建立预测交叉模量的氧化动态模型.研究结果表明，无论是石油沥青还是改性沥青，交叉模量对数的倒数在老化开始一段时间增长速度较快，后期逐渐缓慢趋于线性增长；氧化动态模型可预测沥青经任意温度和任意时间老化后的交叉模量；每种沥青都有其各自的老化路径.
In order to study the dynamic evolution laws of asphalt oxidative aging process，three binders were aged at different temperatures and aging periods.The master curve of complex modulus and phase angle of each binder were determined through frequency sweep tests by using a dynamic shear rheometer，and crossover modulus can be determined further.The dynamic evolution laws of crossover modulus with aging time and temperature were analyzed.The oxidation dynamic model which can predict the crossover modulus was established.It is found that the growth rates of the inverse of log crossover modulus are fast at the beginning aging time，and then gradually get slow to linear for both of unmodified and modified binders.The model can predict the crossover modulus of binders with aging time and temperature.Each binder has its own aging path with aging conditions.