干湿循环作用下SBS改性沥青及其混合料老化行为分析

Analysis on Aging Behavior of SBS Modified Asphalt and its Mixture under the Action of Dry-wet Cycles

为探究干湿循环对SBS改性沥青老化行为的影响,对SBS改性沥青在干湿循环条件下进行8 d、16 d的老化处理,同时设置热氧老化与湿热老化条件作为对照,并对SBS改性沥青及沥青混合料性能进行测试。结果表明:水对SBS改性沥青的老化存在显著影响,且干湿循环环境会显著加快改性沥青的老化;沥青的老化和孔隙水的渗透压力导致沥青混合料的孔隙率增大;在试验过程中环境对SBS改性沥青老化的影响大小依次可分为干湿循环老化、湿热老化、热氧老化。

In order to investigate the influence of dry-wet cycle on the aging behavior of SBS modified asphalt,the SBS modified asphalt compound is aged for 8 d and 16 d under dry-wet cycle respectively.At the same time,the thermal oxidative aging and hydro-thermal aging are used as the control group.Then,the performance of SBS modified asphalt and asphalt mixture is explored.The results show that the presence of water significantly aggravates the damage of asphalt mixture.In addition,the dry-wet cycle environment will significantly accelerate the aging of modified asphalt.The aging of asphalt and the seepage pressure of pore water lead to the increase of porosity of asphalt mixture.The influence of asphalt aging rate in asphalt mixture in experiment environment can be divided into from large to minor perspective is dry/wet cycling aging,wet/heat aging,and thermal-oxidative aging.