混凝土材料的细观结构数值模拟与性能分析

在细观上将混凝土看作是由粗骨料、水泥砂浆和界面三相介质组成的复合材料,根据体视学原理并应用蒙特卡洛方法模拟出混凝土的二维圆形骨料分布;应用理论公式计算出界面厚度,并将界面看作是包围在骨料外面的一层圆环,在细观上模拟生成混凝土的三相组成;基于骨料随机模型,应用有限单元法提出了混凝土稳态氯离子扩散系数的计算方法并与试验结果进行了对比。结果表明,该模型用于计算混凝土稳定氯离子扩散系数是有效的。

Numerical Simulation and Performance Analysis of Concrete Based on Material Mesostructures

Based on the random aggregate model,a finite element method was employed to calculate the steady chloride diffusion coefficient.In the mesolevel,concrete was considered as a three-phase composite material,consisting of aggregate,cement matrix and interfacial transition zone(ITZ).The circle aggregate distribution of meso concrete in two dimensions was simulated on basis of stereological theory and Monte Carlo method.The ITZ was simulated as a ring outside the aggregate after its thickness being calculated.By these methods,the three-phase numerical model of concrete was established.Comparisons between numerical and experimental results were carried out.The results show that the model is effective to calulate the steady chloride diffusion coefficient of concrete.