【摘要】 为满足薄层加铺结构工程需要，以超薄沥青混凝土（ultra-thin asphalt concrete,UTAC）为例，基于材料的细观结构特性，采用数字图像分析和数值仿真方法，对加铺材料的体积特性和虚拟力学性能进行评价。马歇尔试验结果表明，采用CAVF法进行级配优化，可以提高材料的骨架密实度，沥青混合料的高温和抗滑性能得到改善。使用CT扫描和数字图像处理技术可获取混合料试件内部各组分空间分布信息，提出相应均匀性评价指标，并通过对比试验发现UTAC均匀性较好。力学性能方面，设计正交试验方案，通过离散元软件PFC3D进行虚拟三轴剪切试验，分析了集料级配、棱角性、针片状含量对沥青混合料抗剪性能的影响程度。更多还原

【Abstract】 For the sake of fullfilling the engineering requirements of thin layer overlay constructions,based on ultra-thin asphalt concrete(UTAC)overlay structure,taking the meso-structure of materials into consideration,the digital image processing and numerical simulation were employed in this study to conduct a com-prehensive investigation on the volumetric characteristics and mechanical properties of the overlay materials. Enhanced high temperature and anti-skid performance were recognized through the results of Marshall test,which verified that the density of material aggregate structure could be improved employing the CAVF method during gradation design. Besides,CT scanning and digital image processing were applied to extract the spatial distribution of respective phases within asphalt mixtures,while corresponding parameter depicting its homogeneousness was put forward,then comparison confirmed the fairly homogeneousness of UTAC.Additionally,in order to analyze the impact of different factors on the shear strength of material,virtual three-axis shear test was conducted based on discrete element method software,namely PFC,using orthogonal experimental design.更多还原