含孔隙混凝土二维细观建模方法研究

根据混凝土的细观组成和结构特点,对传统二维建模方法加以继承与改进,提出了一种高效的分步入侵判定算法.将孔隙直观地反映在模型中,建立了不同的含孔隙混凝土细观模型.对含圆形、椭圆形、多边形骨料与圆形、椭圆形孔隙的混凝土标准试件分别进行了建模研究,结果表明本文的算法具有较强适用性.同时,通过对不同面积率与多种形状骨料/孔隙混凝土的大量建模进一步验证了该算法的效率.模拟了混凝土试件在单轴压缩下的准静态力学性能,分析了混凝土内部孔隙对其裂纹扩展的主要路径、破坏模式以及宏观力学性能的显著影响.

Study on a 2D Mesoscopic Modeling Method for Concrete With Voids

According to the meso⁃structure of concrete,a high⁃efficiency stepwise overlap checking method was proposed based on traditional 2D modeling.Voids were introduced direct⁃ly into the models and different concrete meso⁃structures were generated.The method involves various models containing circular,elliptical or polygonal aggregates and circular or elliptical voids.Meanwhile,several modeling examples based on different area fractions and different shapes of aggregates and voids were given to prove the computation efficiency of the proposed algorithm.At last,the mechanical behaviors of standard concrete specimens under uniaxial compression were simulated.The effects of internal voids on the main paths of crack propaga⁃tion,concrete failure modes and macroscopic mechanical performances were analyzed.