Reinterpretation of Karihaloo's size effect analysis for notched quasibrittle structures

Karihaloo recently published an analytical study of the size effect in concrete based on large-size asymptotic approximations of the cohesive crack model. From this analysis, he concluded that the nominal strength can be determined only for sizes above a certain lower bound, large enough to invalidate, at least for concrete, all the existing experimental methods based on size effect measurements, such as the size effect method of Bažant or the general bilinear fit method of Planas, Guinea and Elices. The purpose of this paper is to show that this conclusion is misleading, and to explain why.

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