轻骨料混凝土弹性模量预测的数值方法

提出了轻骨料混凝土弹性模量预测的快速傅里叶变换法。将轻骨料模拟成多边形,引入周期性边界条件,将轻骨料分布到正方形区域中而重构轻骨料混凝土细观结构。通过划分网格,等距离选取像素点,利用快速傅里叶变换法获得轻骨料混凝土弹性模量的数值解。通过与文献中的试验结果对比,证实该数值方法具有较高的精度。基于模拟结果,分析了最大轻骨料粒径、界面层厚度和界面弹性模量对轻骨料混凝土弹性模量的影响。数值结果表明,这三个因素的影响处于同一个数量级,在6%~10%之间。

Numerical method for predicting the elastic modulus of lightweight aggregate concrete

A fast Fourier transform method is presented for predicting the elastic modulus of lightweight aggregate concrete.Lightweight aggregates are modeled as polygons.By introducing periodic conditions,lightweight aggregates are distributed in a square domain to reproduce the mesostructure of lightweight aggregate concrete.Through the dividing of meshes and the selection of pixel points,the fast Fourier transform method is used to obtain the numerical solution for the elastic modulus of lightweight aggregate concrete.Through comparison with experimental data obtained from the literature,it is confirmed that the numerical solution is of higher accuracy.Based on the numerical results,the effects of the maximum lightweight aggregate diameter,the interfacial transition zone(ITZ)thickness,and the ITZ elastic modulus on the elastic modulus of lightweight aggregate concrete are analyzed.Numerical results show that the effects of the three factors are at the same order of magnitude,ranging from 6% to 10%.