三相混凝土抗压强度的细观力学研究

Micro-mechanical study on the compression strength of the three-component concrete

从细观力学的角度给出分析外界荷载作用下混凝土受压强度影响的一种解析方法,基于等效夹杂理论求得骨料夹杂和水泥砂浆基体的平均应力场,所提的细观力学模型能同时考虑骨料体积百分比和基体和夹杂的杨氏模量比对混凝土压缩强度的影响。研究发现:骨料的体积百分比存在一个临界值,当大于临界值时,混凝土与界面层抗压强度比随着骨料与基体的杨氏模量比的增大而增大,当小于临界值时,混凝土与界面层抗压强度比随着骨料与基体的杨氏模量比的增大而减小。

A micro-mechanical method is proposed to account for the influence of loading on compression strength of concrete.The average stress fields of aggregate inclusion and motar matrix can be obtained by use of the equivalent inclusion method.This model can account for the influence of aggregate volume fraction and Young′s modulus ratio between matrix and inclusion on concrete compression strength.It is found that,the volume fraction of aggregation exist a critic value,above which the compression strength ratio between concrete and interface increases with the increases of the Young′s modulus between aggregation and matrix,and below this value it is the inverse.