振动成型设计下AC-16沥青混合料的耐久性能

Durability of AC-16 asphalt mixture under vibration molding design

为论证垂直振动法(VTM)设计沥青混合料在光照环境与荷载反复作用环境下的耐久性能,本文首先对VTM法、马歇尔法(Marshall)和旋转压实法(GTM)成型的AC-16混合料力学性能进行对比,并深入分析VTM、Marshall两种设计方法的抗老化性能和耐疲劳特性,应用Weibull分布建立疲劳方程,对疲劳寿命进行对比。结果表明:VTM成型试件具有密实度高、空隙率和矿料间隙率低的特点;GTM、VTM沥青混合料力学性能较Marshall至少提高35%;GTM法、VTM法、Marshall法与现场相关性分别为94%、92%和72%;老化后两种方法设计沥青混合料低温性能相当;短期老化后VTM设计沥青混合料回收沥青性能变化比Marshall的大;长期老化后VTM设计沥青混合料回收沥青性能变化比Marshall的小;建立的Weibull模型呈现良好的线性相关性;不同失效概率下,基于VTM设计的沥青混合料耐疲劳性能优于Marshall法。

In order to demonstrate the durability of asphalt mixture designed by vertical vibration method(VTM)under the environment of light and repeated load,this paper firstly compares the mechanical properties of AC-16 mixture formed by VTM method,Marshall method and rotary compaction method(GTM).The anti-aging performance and fatigue resistance characteristics of VTM and Marshall design methods were deeply analyzed.The fatigue equation was established by Weibull distribution,and the fatigue life was compared.The results show that VTM forming specimens have the characteristics of high compactness,low porosity and ore gap ratio.The mechanical properties of GTM and VTM asphalt mixture are at least 35% higher than those of Marshall.GTM method,VTM method,Marshall method and field correlation were 94%,92% and 72%,respectively.After aging,the low temperature performance of asphalt mixture designed by the two methods is similar.After short-term aging,the performance of VTM design asphalt mixture recovery asphalt changes more than Marshall′s;After long-term aging VTM design asphalt mixture recovery asphalt performance changes less than Marshall;Weibull model presented good linear correlation.The fatigue resistance of asphalt mixture based on VTM design is better than Marshall method under different failure probabilities.