Modelling size effects for static strength of brittle materials

Abstract

The paper proposes a new model for the assessment of size effects affecting the fracture strength of brittle materials. The proposed model permits to accurately estimate the relation between the specimen strength, the initial defect size and to take into account the strength variation with respect to the tested volume.The proposed methodology is analytically defined and thereafter validated with the literature data obtained through tests on different types of brittle materials, and on specimens with increasing volume. A simple procedure for parameter estimation is also defined in the paper. The literature validation proves the effectiveness of the proposed methodology, with the resulting fitting models in well agreement with the experimental dataset and characterized by high values of coefficients of correlation, similar or larger than those obtained in the literature with different approaches.

Keywords

• Size effects
• Scaling
• Uniaxial strength
• Gumbel distribution
• Defect size