基于随机骨料投放的沥青混凝土细观模型研究

Meso mesoscopic model of asphalt concrete based on random aggregate placement

为从细观角度研究沥青混合料,用ABAQUS内置脚本语言python建立一种考虑集料的棱角性、粗集料占比和混合料空隙率的随机骨料投放模型。在建模过程中,以椭圆为基准,引入旋转坐标,用椭圆短轴和随机区间控制骨料的形状。用卡罗蒙特法根据集料级配生成与实际情况较为相符的不规则多边形骨料的沥青混合料二维数字模型。在骨料重叠判定上,直接以多边形骨料本身为目标进行判断而舍弃以椭圆为目标的判断方法。用体视学方法得到沥青混合料的二维级配,制作二维数字试件。通过模拟单轴压缩和单轴拉伸试验,与真实形状的骨料模型进行对比,表明本文生成的二维随机沥青混凝土模型与真实骨料模型较为接近。

In order to study asphalt mixture from a micro perspective,a random aggregate delivery model was built by using ABAQUS built-in script language python.The model considered the Aggregate Angularity,coarse aggregate proportion and mixture porosity.In the process of building the model,the rotating coordinates were introduced with ellipse as the reference,and the shape of the aggregate was controlled by the elliptical short axis and the random interval.Two dimensional digital model of asphalt mixture material card remount method according to the aggregate gradation and the actual situation was consistent with the formation of irregular polygon aggregate.It was more close to the actual situation that the objective of the polygon aggregate itself was judged on the aggregate overlap and the ellipse as the target.The two-dimensional gradation of asphalt mixture was obtained by stereological method,and a two-dimensional digital specimen was made.Through the simulated uniaxial compression and uniaxial tensile test,the comparison with the real shape aggregate model shows that the two dimensional random asphalt concrete model is close to the real aggregate model.