抗车辙剂改性沥青混合料疲劳性能试验研究

Experiment Research on Fatigue Characteristics of Anti-rutting Agent Modified Asphalt Mixture

为研究抗车辙剂改性沥青混合料的疲劳特性,基于三点弯曲疲劳试验通过改变施加应力和加载频率,模拟分析了抗车辙剂掺量、车载水平、车辆速度率等因素对抗车辙剂改性沥青混合料疲劳寿命的影响规律,并与普通沥青混合料抗疲劳性能进行了比较。结果表明,当抗车辙剂掺量超过0.3%时,混合料疲劳寿命降低幅度明显;抗车辙剂改性沥青混合料疲劳寿命随施加应力增加而快速降低,且两者满足幂函数疲劳方程;提高加载频率,混合料的疲劳寿命随之增加,且在低应力水平下,加载频率变化引起的疲劳寿命差异更大。

To obtain fatigue characteristics of anti-rutting agent modified asphalt mixture,the influence rule of anti-rutting agent proportion,vehicle load and vehicle speed on fatigue life of mixture were investigated based on three-point bending fatigue tests though changing the strain level and load frequency.Further,the fatigue characteristic of common asphalt mixture was also investigated to be compared with the anti-rutting agent modified asphalt mixture.Results show that there is an obvious decrease in the mixture＇s fatigue life when the proportion of anti-rutting agent is over 0.3%.The power function model is suitable for describing the relationship between fatigue life and strain level,which presents that the fatigue life reduces rapidly with the increase of applied stress.In addition,increase in loading frequency results in an increase in the fatigue lives of asphalt mixture,and the difference in fatigue lives at different loading frequencies is found to be higher at lower stress levels.