An analytical study on the compression, tension and shear strengths of concrete and corresponding size effect is conducted using the meso-scale finite-element method (FEM). Prior to the analysis, a method of defining concrete as a meso-scale composite and multi-phase is described. The concrete is assumed to be a composite with three phases: aggregates, cement matrix and interfacial transition zone. The material properties of each phase are applied. Behaviours relating to uniaxial and flexural compressive failure, splitting and direct tensile failure of concrete, and shear failure of reinforced concrete are analysed using the model constructed; the size effect is confirmed through these analyses. The performance of the analytical models is also evaluated by comparing experimental with analytical results. Finally, it is confirmed that the application of the meso-scale size analysis model is enough when studying the occurrence and progress of tensile cracks. This basic study represents a fresh application of meso-scale FEM analysis to concrete; in future research, the authors will apply meso-scale FEM analysis in a wider variety of fields.

中文翻译：

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细观有限元法在混凝土强度和尺寸效应中的应用

采用细观有限元法（FEM）对混凝土的抗压、抗拉和抗剪强度及相应的尺寸效应进行了分析研究。在分析之前，描述了一种将混凝土定义为中尺度复合材料和多相的方法。混凝土被假定为具有三个阶段的复合材料：骨料、水泥基体和界面过渡区。应用每个相的材料属性。使用所构建的模型分析了与混凝土的单轴和弯曲压缩破坏、劈裂和直接拉伸破坏以及钢筋混凝土的剪切破坏有关的行为；通过这些分析证实了规模效应。分析模型的性能也通过将实验结果与分析结果进行比较来评估。最后，证实了在研究拉伸裂纹的发生和发展过程中，应用细观尺寸分析模型就足够了。这项基础研究代表了中尺度有限元分析在混凝土中的新应用；在未来的研究中，作者将在更广泛的领域应用中尺度有限元分析。