Abstract Combining the advantages of the size and the boundary effect models, an improved fracture model for determining the material parameters of concrete is proposed in this paper, considering concrete aggregate grading. The simple method for determining the fictitious crack growth length at peak loads of concrete specimens is identified through quantitative research. The independent fracture toughness and tensile strength of concrete can be determined with the maximum value of correlation coefficients in curve fitting, and the effect of maximum aggregate size, water to cement ratio, and coarse aggregate volume on fracture can be fully considered. A total of 300 self-compacting concrete specimens are used for analysis to verify the applicability and feasibility of the proposed model. The full structural fracture failure curves of concrete with upper and lower limits covering the experimental peak loads are established on the basis of the normal distribution methodology.

中文翻译：

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考虑骨料级配的混凝土断裂

摘要 本文结合尺寸模型和边界效应模型的优点，提出了一种考虑混凝土骨料级配的改进的确定混凝土材料参数的断裂模型。通过定量研究确定了确定混凝土试件峰值载荷下假想裂纹扩展长度的简单方法。通过曲线拟合中相关系数的最大值可以确定混凝土的独立断裂韧度和抗拉强度，并且可以充分考虑最大骨料粒径、水灰比、粗骨料体积对断裂的影响。共使用300个自密实混凝土试件进行分析，验证了所提出模型的适用性和可行性。