基于正交试验的废轮胎胶粉改性沥青微观特性研究

Study on microcosmic properties of waste tire rubber powdermodified asphalt based on orthogonal test

通过4水平4因素正交试验设计方案制备了废轮胎胶粉改性沥青,并对最优组合胶粉改性沥青进行了薄膜烘箱老化试验。通过对沥青基础指标的测试及傅里叶变换红外光谱、四组分及热重的分析,从宏观角度评价了不同沥青的性能变化,微观角度分析了胶粉改性沥青的化学组分及变化规律。研究结果表明,胶粉改性沥青的最优配比组合为胶粉掺量17%(质量分数,下同)、搅拌温度180℃、改性剂质量配比1/6和增塑剂掺量4%。用胶粉改性后沥青的红外光谱特征吸收峰的形状及位置未变,但强度发生变化;使化学组分的含量产生了变化,饱和分和芳香分减少、胶质和沥青质增加。胶粉的掺入降低了沥青的热降解速率,提高了初始降解温度及最终残留物含量,改善了沥青的热稳定性。

Modified asphalt with waste tire rubber powder was prepared by using orthogonal experimental design of four levels and four factors.Aging test of film oven was carried out with the optimized combination of rubber powder modified asphalt.The performance changes of different asphalts were evaluated from macroscopic point of view,and chemical components and revolution of rubber modified asphalt were analyzed from microscopic point of view by three major indicators of asphalt,infrared spectroscopy,four component analysis and differential thermal test.The results showed that the optimal ratio of modified asphalt was 17%(mass fraction,the same below)of rubber powder amount,180℃of mixing temperature,1/6 of modifier mass ratio and 4%of plasticizer amount.The shape and position of the characteristic infrared absorption peak of asphalt modified with rubber powder remained unchanged,but intensity changed.Meanwhile,the content of chemical components was changed.The components of saturated and aromatic decreased,but resin and asphaltene components increased.The addition of rubber powder reduced degradation rate of the asphalt,increased initial degradation temperature and final residue content,and improved thermal stability of the asphalt.