废机油底渣再生剂对老化沥青低温性能影响

为准确评估废机油底渣(WEOB)作为沥青再生剂时对老化沥青低温性能的影响,通过室内旋转薄膜烘箱老化(RTFOT)和40h长期老化(PAV)试验制备老化沥青,然后采用双边缺口拉伸(DENT)试验、扩展弯曲梁流变(Ex-BBR)试验分别研究了原样沥青、老化沥青和添加废机油底渣再生沥青的抗延性断裂性能,以及物理硬化对这3种沥青低温极限分级的影响;采用原子力显微镜研究了原样沥青、老化沥青和再生沥青的微观结构.结果表明:使用废机油底渣会降低老化沥青的容许应变(CTOD)和常规弯曲梁流变仪的低温极限分级,经过长期低温恒温处置后,废机油底渣掺量为10%的再生沥青低温极限分级增加明显;老化沥青中添加废机油底渣并不能恢复原样沥青胶结料的表面微观形态,而且形成了更多的相界.

Effect of Waste Engine Oil Bottom Rejuvenator on Performance of Aged Asphalt

In order to accurately evaluate the effect of waste engine oil bottom(WEOB) as an asphalt rejuvenator on the performance of aged asphalt binder, the aged asphalt was prepared by RTFOT and 40h PAV test. Using double edge notched tension(DENT) test, extend bending beam rheometer(Ex BBR) test to characterize ductile fracture and low temperature performance of original, aged and recycled asphalt. Using atomic force microscope to characterize microstructures of three states of asphalt. The results show that the use of WEOB can reduce the tolerant strain(CTOD) and low temperature limiting grade of conventional bending beam rheometer(BBR). The low temperature limiting grade of recycled asphlt with 10% WEOB contents after long term low temperature storage shows significant increase. The microstructure of asphalt with WEOB added shows that WEOB can not restore topographical microstructure and forms more phase boundary.