矿料级配及空间分布对混合料性能的影响

为了了解沥青混合料中矿料自身几何特性、分布及混合情况对混合料性能的影响，利用有限元方法构建单多颗集料模型并探究其力学特性，之后模拟三种特定沥青混合料结构进行分析对比，最后优化级配曲线。结果如下：胶浆与集料的交界面上易出现应力极值及损伤；集料间垂直距离对等效应力的影响大于水平距离；与骨架～空隙结构相比，骨架一密实结构、悬浮一密实结构抗剪性能与承栽性较好；AC－13最佳级配曲线在规范级配中值下方，颗粒偏粗。结果表明矿料中集料的细观力学特性决定沥青混合料的宏观承载能力，为更好地研究沥青混合料内部不均匀性引起的力学行为提供了新的思路。

Study on Influence of Mineral Aggregate Gradations and Spatial Distribution on Asphalt Concrete

In the paper, to find out the influence of geometric characteristics, distribution and combination condition of mineral aggregates on mixture properties, the single and multi aggregates particle modulus are built using finite element method and the mechanical properties of aggregates is discussed. Later three representative asphalt mixture structures with different gradations are given a contrastive analysis. Finally the optimal gradation curve is obtained. The simulation results are as follows： The interface between mortar and aggregate is prone to extreme values or damage of stress ; The impact on the equivalent stress for aggregate space in vertical direction is greater than in horizontal direction; Compared to ＂framework - pore＂ structure, the ＂suspend - dense＂ structure and ＂framework - dense＂ structure have better shear resistance behavior and load - carrying capacity; The best AC - 13 gradation curve below specification intermediate gradation curve and the mineral aggregates are inclined to coarse particles. The paper concludes that the mechanical properties microcosmically of aggregates determine carrying capacity macroscopically of asphalt mixtures, and further it is a new idea provided for studying mechanical behavior due to internal heterogeneity of asphalt mixture.