Xie Hao, Feng Jili
State Key Laboratory for Geomechanics and Deep Underground Engineering, China University of Mining and Technology Beijing, Beijing 100083, China.
Materials (Basel). 2019 Nov 21;12(23):3835. doi: 10.3390/ma12233835.
We develop a dot matrix method (DMM) using the principles of computational geometry to place aggregates into matrices for the construction of mesolevel concrete models efficiently and rapidly. The basic idea of the approach is to transform overlap detection between polygons (or polyhedrons) into checking the possibility of any intersection between the point sets within a trial placement aggregate and the already placed ones in mortar. Through the arithmetic operation of integer point sets, the efficiency of the underlying algorithm in the dot matrix method is higher. Our parking algorithm holds several advantages comparing with the conventional placement issues. First, it is suitable for arbitrary-shape aggregate particles. Second, it only needs two sets for examining if the overlap between a trial placement aggregate and the already placed ones. Third, it accurately places aggregates according to aggregate grading curves, by order of reduction, led to more efficiently reducing aggregate placement time. The present method is independent of the size of aggregate particles. Combing with 3D laser scanning technology, the present method can also be used to create mesostructure concrete models conveniently and flexibly. Several examples show that DDM is a robust and valid method to construct mesostructure concrete models.
我们利用计算几何原理开发了一种点阵方法（DMM），以便将骨料放置到矩阵中，从而高效快速地构建细观混凝土模型。该方法的基本思想是将多边形（或多面体）之间的重叠检测转化为检查试验放置骨料内的点集与砂浆中已放置骨料的点集之间是否存在任何交集的可能性。通过整数点集的算术运算，点阵方法中底层算法的效率更高。与传统的放置问题相比，我们的放置算法具有几个优点。首先，它适用于任意形状的骨料颗粒。其次，它只需要两组数据来检查试验放置骨料与已放置骨料之间是否重叠。第三，它根据骨料级配曲线按递减顺序准确放置骨料，从而更有效地减少骨料放置时间。本方法与骨料颗粒的大小无关。结合三维激光扫描技术，本方法还可方便灵活地创建细观结构混凝土模型。几个例子表明，DDM是构建细观结构混凝土模型的一种可靠且有效的方法。
