采用动态剪切流变仪(DSR),在应力加载模式下对不同厚度的沥青试样进行时间扫描试验。采用N_(f50)、N_(p20)和N_(fm)三种疲劳评价指标对沥青的疲劳寿命进行评价和对比分析,比较不同试样厚度条件下沥青的疲劳寿命,为选择沥青疲劳破坏的评价指标提供依据。结果表明:当沥青试样厚度不同时,由不同的沥青疲劳评价指标所得到的疲劳寿命存在一致性排序,即N_(p20)
The dynamic shear rheometer(DSR) was adopted to evaluate the fatigue performance of asphalt with different specimen thickness under the stress controlled mode time sweep (Time Sweep). The fatigue characteristics were evaluated and compared by three indexes (Nf50, Np20 and Nfm. In order to provide reference for the fatigue failure indexes of asphalt, the fatigue test of asphalt with different specimen thickness was conducted. The results show that the fatigue life of asphalt with different specimen thickness evaluated by different indexes has a consistent order,namely Np20〈Nf50〈Nfm. Nf50 has the highest distinction with different asphalt specimen thickness and Nf50 is recommended as an evaluated and compared fatigue index of asphalt. When the asphalt specimen thickness is 500μm, the asphalt has the maximum fatigue life.