基于统计学的再生沥青混合料疲劳性能试验研究

为研究再生沥青混合料(reclaimed asphalt pavement,RAP)掺量、温度、行车速度、车辆轴重对再生沥青路面疲劳寿命的影响,通过开展多因素(RAP掺量、试验温度、加载频率、控制应变)多水平的再生沥青混合料小梁四点弯曲疲劳试验,采用统计学方法分析了RAP掺量、试验温度、加载频率、控制应变对再生沥青混合料疲劳寿命与疲劳方程的关系,并改进了疲劳方程.结果表明:RAP掺量、控制应变、加载频率、试验温度对疲劳寿命影响的显著性较高,但RAP掺量与其他三因素的交互效应显著性不明显;四因素对再生沥青混合料疲劳寿命的影响程度为控制应变>试验温度>RAP掺量>加载频率;佩尔疲劳模型适用于再生沥青混合料疲劳寿命研究,此模型中的系数与RAP掺量、试验温度、加载频率相关度较高,此三因素可通过非线性拟合引入疲劳模型,且改进后的疲劳模型可靠度较高.

Fatigue Performance of Recycled Asphalt Mixture Based on Statistics

In order to study the the influence of reclaimed asphalt pavement (reclaimed asphalt pavement,RAP) content, temperature, driving speed and vehicle axle load on the fatigue life of recycled asphalt pavement, Four point beam bending fatigue test with multiple factors (RAP content, test temperature, loading frequency, test strain) and multilevel was conducted, and the relationship between RAP content, test temperature, loading frequency, test strain and fatigue performance was analyzed by statistical method, and the fatigue equation was improved. The results show that: the RAP content, test strain, loading frequency and test temperature have a great influence on fatigue life, but the influence between RAP content and other three factors was not significant; The degree of influence of four factors on fatigue life of recycled asphalt mixture is test strain > test temperature >RAP content > test frequency; The Pell Model is suitable for the study of fatigue life of recycled asphalt mixture, and coefficients in this model are highly correlated with test temperature, RAP content and test frequency. The above three factors can be introduced into the model through nonlinear fitting, and the improved fatigue model has higher reliability.