| 摘要: |
| 为研究热老化作用下沥青胶浆的自愈合特性，针对3种沥青胶浆，利用原子力显微镜（AFM）、动态剪切流变仪（DSR）、弯曲梁流变仪（BBR）进行微观结构、疲劳—愈合—再疲劳、蠕变—愈合—再蠕变测试，通过2个愈合指数（HI1和HI2）研究了愈合温度、沥青种类、粉胶比、老化程度、破坏程度及愈合时间对沥青胶浆自愈合性能的影响.结果表明：老化后基质沥青胶浆中“蜂形结构”变化显著，而老化后SBS改性沥青胶浆和胶粉改性沥青胶浆的微观结构较为稳定，微观结构的改变潜在影响沥青胶浆的自愈合性能；基于累计耗散能建立的愈合指数HI1和基于时间轴与劲度模量主曲线在双对数坐标下所围面积SA而建立的愈合指数HI2能很好地反映沥青胶浆的自愈合性能；低粉胶比沥青胶浆的自愈合能力更好，老化程度的加深导致沥青胶浆的自愈合能力降低，经历低温后改性沥青胶浆的愈合能力较好. |
| 关键词: 热老化 自愈合 沥青胶浆 微观结构 流变性能 愈合机理 |
| DOI：10.3969/j.issn.1007-9629.2021.06.020 |
| 分类号:U414; |
| 基金项目:国家自然科学基金资助项目（51568054）；内蒙古自治区高等学校“青年科技英才计划”项目（NJYT-19-A19）；内蒙古自然科学基金资助项目（2018MS05053） |
|
| Evaluation of Microstructure and Self-healing Properties of Asphalt Mortar under Heat Aging |
|
CUI Yanan1,2, ZHOU Jun1,2, ZHAO Lin3
|
|
1.School of Civil Engineering， Inner Mongolia University of Technology， Hohhot 010051，China;2.The Key Laboratory of Civil Engineering Structure and Mechanics of Inner Mongolia Autonomous Region，Inner Mongolia University of Technology， Hohhot 010051，China;3.School of Transportation and Municipal Engineering， Inner Mongola Techical College of Construction， Hohhot 010051，China
|
| Abstract: |
| In order to study the self-healing properties of asphalt mortar under heat aging， three kinds of asphalt mortar were prepared to test microstructure， fatigue—healing—re-fatigue and creep—self-healing—re-creep processes，by atomic force microscope（AFM），dynamic shear rheometer（DSR），bending beam rheometer（BBR） to establish two healing indexes （HI1 and HI2） for the effects of healing temperature， asphalt type， filler-asphalt ratio， aging degree， destruction degree， healing time on the self-healing properties of asphalt mortar. The results show that after aging， the bee-shape structure in the matrix asphalt mortar changes significantly， while the microstructure of SBS modified asphalt mortar and rubber powder modified asphalt mortar is more stable， and the change of microstructure potentially affects the self-healing performance.The healing index HI1 based on the cumulative dissipation energy and the healing index HI2 based on the area SA enclosed by the time axis and the main curve of the stiffness modulus in double logarithmic coordinates can better reflect the asphalt mortar self-healing properties； The self-healing ability of asphalt mortar with low filler-asphalt ratio is better， the deepening of aging reduces the healing ability， and the healing ability of modified asphalt mortar is stronger at low temperature. |
| Key words: heat aging self-healing asphalt mortar microstructure rheological property healing mechanism |
