利用离散元模型分析沥青混合料的空隙特性

Analysis of Void Characteristics of Asphalt Mixtures with Discrete Element Method Model

空隙是沥青混合料细观结构特性的重要组成部分,水和空气存在于其中时会造成混合料的水损害与老化,另外空隙也是混合料结构中的薄弱点与缺陷,与混合料的受力特性与破坏过程紧密相关.该文利用离散元工具生成了具有级配特征的沥青混合料颗粒流模型,移植借鉴离散元流固耦合分析的方法来计算混合料中各空隙的位置与体积等参数,得到了混合料中的空隙分布特性,并与实际混合料试件上使用CT扫描与图像分析得到的结果进行了对比,证明了论文所用分析方法的有效性.

Voids play an important role in the micro structure characteristics of asphalt mixtures, since moisture damage and aging will occur with the existing of water and air. In addition, voids are the weak points and defects in the mixture which are closely related to the force bearing performance and the damage process. A graded particle flow model of asphalt mixture was built up using discrete element method （DEM） package. The DEM fluid coupling analysis framework was used to calculate the parameters of each void such as volume and position. Finally the obtained voids distribution pattern was compared to actual results from CT scan and image analysis. It proves that the scheme employed in the paper is effective and reasonable.