考虑骨料形状效应时混凝土界面面积率的计算

Calculation of ITZ area fraction in concrete with aggregate shape effect

提出了考虑骨料形状效应时混凝土界面面积率的数值算法。通过引入辅助椭圆,构造出八边形骨料。根据模拟所得的骨料分布,应用蒙特卡洛数值方法计算界面面积率。通过数值算法的有效性得到圆形骨料混凝土界面面积率解析解的证实后,定量评价了影响界面面积率的关键因素,发现界面面积率随着界面厚度的增大而增大,但随着最大骨料直径和骨料形状系数的增大而减小,也发现骨料级配对界面面积率有重要影响。

A numerical algorithm for the interfacial transition zone （ITZ） area fraction in concrete with aggregate shape effect is developed.By introducing an auxiliary ellipse,the octagonal aggregate is constructed.With the simulated aggregate distribution,the Monte Carlo numerical method is adopted to evaluate the ITZ area fraction.After verifying the developed numerical algorithm with the analytical solution for the ITZ area fraction in concrete with circular aggregates, the effects of key factors that affect the ITZ area fraction are evaluated in a quantitative manner.It is found that the ITZ area fraction increases with the increasing of the ITZ thickness,but decreases with the increasing of the maximum aggregate di- ameter and the aggregate shape coefficient.It is also found that the aggregate gradation fias a significant influence on the ITZ area fraction.