复杂环境因素影响下沥青混合料自愈合性能

Self healing Properties of Asphalt Mixture under Different Factors

关键词:  沥青混合料  自愈合  正交试验  半圆弯拉试验  数字散斑技术

Key words:  asphalt mixture  self healing  orthogonal test  semi circular bending test  digital speckle technique

摘要:

通过半圆弯拉试验，以断裂能密度为愈合指标，分别研究了沥青种类、损伤程度、老化程度、愈合温度及愈合时间对沥青混合料自愈合性能的影响，并运用数字散斑技术对其损伤和自愈合过程进行了观测.结果表明:损伤程度对沥青混合料的自愈合能力影响最为显著；胶粉改性沥青混合料的自愈合效果最好；损伤程度和老化程度对自愈合能力起负面作用；当提高愈合温度时，沥青混合料的自愈合能力增强；随着愈合时间的增加，沥青混合料自愈合速度相对降低；基质沥青混合料经过短期老化后裂缝自愈合速度最快.

Abstract:

Through the semi circular bending test, the five influence factors such as the asphalt type, damage degree, aging degree, healing temperature and healing time were analyzed for the self healing properties of asphalt mixture when the fracture energy density as a healing index. The damage and healing process of the specimens were observed by digital speckle technique.The results indicate that the damage degree has the most significant influence on self healing ability of asphalt mixture. The self healing effect of crumb rubber modified asphalt mixture is the best. The damage degree and aging degree have a negative effect on the self healing ability. When the healing temperature is increased, the self healing ability of asphalt mixture is enhanced. The self healing speed is decreased with the increase of the healing time. The crack self healing rate of the matrix asphalt mixture after short term aging is the highest.