二维骨料分布边界效应的计算机模拟

Computer Simulation of Two-dimensional Aggregate Distribution with Wall Effect

讨论了二维骨料分布的边界效应.首先,应用一种简单的模拟算法,分析了混凝土骨料分布密度的边界效应和边界层形成机理.模拟结果表明,当模拟次数趋向无穷大时,混凝土构件中任一点的骨料分布密度均值均趋近于某一定值.不同的骨料面积分数并未影响骨料分布密度均值曲线的形状,它们均由上升段、下降段和水平段三部分组成;其次,基于这些模拟结果,再应用数学拟合将骨料分布密度均值和边界层厚度表示成骨料面积分数的函数;最后,用实验数据初步证实了该模拟算法的有效性.

The wall effect of twodimensional aggregate distribution was discussed. Firstly, the wall effect of the aggregate distribution density of concrete and the formation mechanism of boundary layers were investigated by applying a simple simulation algorithm. Simulation results show that the mean aggregate distribution density at any point in a concrete member converges to a constant asymptotically when the number of simulations tends to infinity. For different aggregate area fractions, the shape of mean aggregate distribution density curves is very similar, which all consist of three parts: ascending, descending and horizontal. Secondly, based on these simulation results, the aggregate distribution density and the thickness of boundary layers are expressed analytically in terms of the aggregate area fraction by using mathematical regression. Finally, the effectiveness of the simulation algorithm presented in this paper is preliminarily verified by a concrete experiment.