基于动态老化方程的沥青抗老化性能对比研究

Comparative Study on Anti-aging Performance of Asphalt Based on Dynamic Aging Equation

对4种沥青进行不同时间的RTFOT老化试验,采用动态方程进行拟合,得到了沥青针入度、延度、软化点、黏度的老化参数和老化方程;以针入度、延度、软化点、黏度的老化参数L和r为评价指标,采用灰色关联理论综合评价不同沥青的抗老化性能.结果表明:针入度、软化点、延度和黏度与老化时间存在非线性关系,在初始期,老化速率大,随着时间的推移,老化速率趋于缓慢;沥青的老化过程可用动态方程表征,其老化参数L和r能很好表征老化度和老化速率,不同沥青、不同指标的老化参数排序不一致;采用灰色关联理论评价4种沥青的抗老化性能排序为:室内制备改性沥青>90#A级基质沥青>成品改性沥青>70#A级基质沥青.

RTFOT aging tests at different aging time for four kinds of asphalt were carried out and the aging test data were fitted to dynamic equation. The aging parameters and aging equation of penetration, ductility, softening point and viscosity of different asphalts were determined. The grey relational theory was utilized to assess the anti-aging performance of different asphalts setting the L and r of penetration, ductility, softening point and viscosity as assessment indicators. The results show that there are nonlinear relationship between penetration; softening point, ductility, viscosity and aging time~ the aging rate rea- ches the peak at the beginning and becomes smaller as the variation of aging time~ the aging process of as phalt can be described accurately by dynamic equation and parameters L and r can be a good characterization of aging degree and aging rate, and the sort of aging parameters of different asphalts and indicators is inconsistent. The sort of anti-aging performance of four kinds of asphalt is determined with grey relational theory as following., indoor produced modified asphalt matrix 90 asphaltfinished modified asphaltmatrix 70 asphalt.