In this paper, a model for the assessment of size effects on quasi‐static strength of brittle materials subjected to applied load inducing a nonuniform stress distribution within the material volume is proposed. An equivalent stress computed through finite element analysis is introduced in the model to account for the effect of the stress gradient within the loaded volume. The defect size distribution is modelled, differently from the literature, with the largest extreme value distribution. The proposed model has been validated with datasets available in the literature and obtained through bending tests on concrete specimens. For each type of test, the model permits to properly assess size effects. Due to its general formulation, a model for the strength variation with respect to the loaded volume, regardless of the testing type, was also obtained, further proving its effectiveness.

中文翻译：

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脆性材料在多轴非均匀应力状态下的静态强度：一种用于评估尺寸效应的新型统计模型

本文提出了一个模型，该模型用于评估尺寸对脆性材料准静态强度的影响，该脆性材料在施加载荷的情况下会引起材料体积内的应力分布不均匀。通过有限元分析计算出的等效应力被引入模型中，以说明加载体积内应力梯度的影响。与文献不同的是，缺陷尺寸分布的模型具有最大的极值分布。所提出的模型已通过文献中可用的数据集进行了验证，并通过对混凝土样本进行弯曲试验获得。对于每种类型的测试，模型都可以正确评估尺寸效果。由于采用了通用公式，因此无论测试类型如何，都可以得出相对于加载体积的强度变化的模型，