混凝土随机骨料模型尺寸效应的细观数值分析

为研究混凝土材料细观不均匀性对试件的静力学性能的影响，采用不同的随机数组，通过固定骨料尺寸，改变试件尺寸的方法，建立了不同的混凝土三维数值模型，都分6步施加相同的均布载荷，来模拟骨料和混凝土试件尺寸比例变化对试件力学性能的影响，研究了骨料随机位置对混凝土试件的应变影响。计算表明，当骨料半径和试件半径的比例系数逐渐增大时，应变误差平方和减小；骨料随机位置对混凝土试件的应变影响逐渐减小，试件的脆性越明显

Numerical analysis of size effect on meso-concrete random aggregate model

In order to research that the effect of meso-concrete material heterogeneity on the static properties of concrete cylinder sample, different random numbers are employed; aggregate size is fixed and size of the concrete samples is changed; different three-dimensional numerical models of concrete are established; the same uniform load is divided into six steps to impose on the models; the effect of various ratios between aggregate and sample radii on mechanical properties of concrete is simulated. The results show that: with the ratio increasing, the error square sum of strain is reduced. The effect of aggregate random location on the concrete samples is decreased; and the brittleness of the samples becomes obvious.