混凝土界面过渡区弹性模量分布的数值模拟

混凝土界面过渡区是混凝土中的薄弱环节,其力学性能直接影响混凝土的强度。但因混凝土界面过渡区的尺寸太小,难以直接通过试验测量其力学性能。在处理界面微观结构照片得到孔隙率分布的基础上,通过ABAQUS软件对不同孔隙率的界面过渡区模型进行单向压缩数值模拟,得出混凝土界面过渡区孔隙率与弹性模量之间的定量对应关系,从而得到界面过渡区弹性模量的分布曲线。结果表明,混凝土界面过渡区的弹性模量不是均匀分布,其变化曲线可以用二次函数表征,越靠近砂浆的地方界面的弹性模量越接近砂浆的弹性模量,且变化率较大。

Numerical simulation of ITZ elastic modules distribution of concrete

Interfacial transition zone(ITZ)is a weak link in concrete,and its mechanical properties directly affect the strength of concrete.The size of ITZ is too small to measure its mechanical properties directly through experiments.The porosity distribution was obtained by processing the micro-structure photos of the interface.Elastic modulus was calculated by unidirectional compression numerical simulation of interface transition zone models with different porosity using ABAQUS software.Quantitative correspondence between porosity and elastic modulus was obtained as well as distribution curve of elastic modulus in interface transition zone of concrete.The results show that the elastic modulus of concrete interface transition zone is not uniformly distributed,and its change curve can be characterized by quadratic function.The elastic modulus of the interface closer to the mortar is closer to the elastic modulus of the mortar,and the change rate is larger.