摘要
混凝土在建筑、水利、海洋和道路工程中应用广泛,其弹性模量是结构变形计算的关键参数.将混凝土细观结构模拟与快速傅里叶变换相结合,提出了混凝土弹性模量预测的数值方法.考虑周期性边界条件给出了多边形骨料和界面在水泥石基体中的随机分布模拟方法.利用快速傅里叶变换方法给出了三相混凝土在外荷载作用下的平均应力、平均应变和弹性模量.将数值方法与文献中的试验数据进行比较,结果表明:当骨料面积百分数分别为40%,60%时,它们之间的相对误差小于5%,初步验证了该数值方法的有效性.基于数值结果,量化了界面弹性模量和厚度对混凝土弹性模量的影响,发现提高界面弹性模量或减小界面厚度都可以有效提高混凝土弹性模量.
Concrete has been widely used in construction, hydraulic, ocean, and road engineering and its elastic modulus is a key parameter for computing the deformations of structures. By combining the numerical simulation technique of the mesostructure of concrete with the fast Fourier transform, a numerical method is presented for predicting the elastic modulus of concrete. With the periodic boundary conditions, a random distribution simulation method is proposed for polygonal aggregates and interfacial transition zones （ITZs） in a cement paste matrix. The fast Fourier transform is used to give the average stress, average strain, and elastic modulus of three-phase concrete subjected to external forces. A comparison between the numerical method and the experimental data obtained from the literature is made. It is found that, when the aggregate area fraction is equal to 40% and 60%, the relative error between them is smaller than 5%, which preliminarily verifies the validity of the numerical method. Based on the numerical results, the effects of the elastic modulus and thickness Of ITZ on the elastic modulus of concrete are quantified. It is found that increasing the elastic modulus of and/or decreasing the thickness of ITZ increase the elastic modulus of concrete.
作者
周欣竹
钱梦必
郑建军
ZHOU Xinzhu QIAN Mengbi ZHENG Jianjun(College of Civil Engineering and Architecture, Zhejiang University of Technology, Hangzhou 310014, China Zhejiang Key Laboratory of Civil Engineering Structures ~ Disaster Prevention and Mitigation Technology, H angzhou 310014, China)
出处
《浙江工业大学学报》
CAS
北大核心
2017年第4期445-448,472,共5页
Journal of Zhejiang University of Technology
基金
国家自然科学基金资助项目(51379188)
浙江省自然科学基金资助项目(LY15E090006)
浙江省科技计划项目(2016C33106)
关键词
混凝土
弹性模量
快速傅里叶变换
多边形骨料
界面层
concrete
elastic modulus
fast Fourier transform
polygonal aggregate
interracialtransition zone
