剪切温度对生物废油改性胶粉沥青的影响

研究剪切温度对生物废油改性胶粉沥青性能的影响，选择50号和70号基质沥青为研究对象，分别加入等量的生物废油和橡胶粉，剪切时间相同，制备不同剪切温度下的生物废油改性胶粉沥青样品，通过黏度、动态剪切流变试验和弯曲梁流变试验研究不同剪切温度下沥青样品流变性能的变化。对沥青样品进行短期老化和长期老化试验，研究沥青老化后性能的变化。借助傅里叶红外光谱试验研究沥青样品中官能团的变化，揭示剪切温度影响的微观机制。结果表明：随着剪切温度的提高，生物废油改性胶粉沥青的黏度、高温性能、中温性能和低温性能均先增强后减弱，且具有定的抗老化能力；生物废油促进了胶粉的溶胀；高温剪切，沥青老化明显，胶粉发生脱硫降解反应，导致沥青性能降低；生物废油改性胶粉沥青的最佳剪切温度为145~155℃。
The influence of shear temperature on waste bio-oil (WBO) modified crumb rubber asphalt was investigated. Pen50 and Pen70 neat asphalts were chosen as base binders in this research. The WBO-modified crumb rubber asphalt samples were prepared at different shear temperatures for the same shear time and with the same contents of WBO and crumb rubber. Rheological properties of asphalt samples were then evaluated through viscosity test, dynamic shear rheometer test and bending beam rheometer test, respectively. And the properties of the aged asphalts were investigated after the asphalt samples were aged with laboratory short-term and long-term aging methods. Moreover, the microscopic mechanism of shear temperature was analyzed by studying the functional groups of the asphalt samples in Fourier transform infrared spectrum. The experimental results indicate that with the increase of shear temperature, the viscosity, high-temperature performance, medium-temperature performance, as well as the low-temperature performance of the modified asphalts were improved firstly, then declined. And the modified asphalts present aging resistance. It is also found that WBO enhances the rubber swelling. In addition, aging of asphalt is distinct and devulcanization as well as degradation happens of crumb rubber at high shear temperature, which causes the degradation of asphalt performance. On the basis of the experiment the optimum shear temperature of WBO-modified crumb rubber asphalt is from 145℃ to 155℃