【摘要】 对AH-90基质沥青及PG70-28改性沥青分别进行了室内旋转薄膜烘箱老化、压力老化及室外光氧老化试验,采用针入度、针入度指数、延度、软化点等指标分析考察了室内热氧老化对沥青高温稳定性、低温开裂性及温度敏感性能的影响。结果表明:老化降低了沥青的低温抗裂性能,改善了沥青的抗高温变形性能和对温度的敏感性,改性沥青的抗老化性能明显优于基质沥青。采用粘温指数法、老化指数法分别考察了光氧老化及热氧老化沥青的感温性能和抗老化性能。结果表明,粘温指数法和针入度指数法具有较好的相关性,总辐射能为10.5 kJ/cm2的室外紫外光照射对沥青感温性能和路用性能的影响比PAV老化严重,在内蒙古强紫外线地区沥青路面设计时需充分考虑光老化带来的危害。更多还原

【Abstract】 This paper studied the aging effects of the rolling thin film oven test(RTFOT),pressurized aging vessel(PAV) and natural ultraviolet radiation aging method on AH-90 and PG70-28 SBS modified asphalts.Penetration degree,penetration degree index,softening point and ductilitytests were used to evaluate the high temperature stability,low temperature split and temperature susceptibility of the two aged asphalts,it is pointed that aging damaged the low temperature performance of the asphalts,improved the high temperature stability and the temperature susceptibility of the asphalts.Compared with the AH-90 asphalt,PG70-28 modified asphalt has better aging performances.The antiaging property and temperature susceptibility of two asphalts after ultraviolet photooxidation and thermal oxidation were investigated by testing their viscosity index,aging index,which indicated that the viscosity index is well correlative with the penetration degree index and the influence of 10.5 kJ/cm2 ultraviolet photooxidation on asphalt performance is more serious than PAV thermal oxidation.The results indicate that ultraviolet photooxidation research on asphalt is necessary in the intensive ultraviolet radiation region of Inner Mongolia.更多还原