PSI - Issue 37

Jesús Toribio et al. / Procedia Structural Integrity 37 (2022) 1029–1036 Jesús Toribio / Procedia Structural Integrity 00 (2021) 000 – 000

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5. Conclusions The dimensionless stress intensity factor (SIF) increases with the relative crack depth ( a/D ), decreases with the crack aspect ratio ( a/b ) and changes continuously from the crack center to the crack surface, increasing or decreasing as a function of these two extreme values (center and surface). For each relative crack depth ( a / D ), the dimensionless SIF at the crack center is higher for straight-fronted edge cracks ( a/b =0) than for circular edge cracks ( a/b =1), i.e., the K -value at the crack center decreases as the curvature of the crack increases. The most adequate K -solution depends on the number of parameters involved in the analysis, namely: (i) when only one parameter such as the relative crack depth ( a / D ) is required, the solution by Valiente is very adequate for straight-fronted (or very slightly-curved) edge-cracks; (ii) when two parameters such as the relative crack depth ( a / D ) and the crack aspect ratio ( a/b ) are needed, the solution by Astiz is the most adequate for obtaining the SIF at the crack center (it exhibits the best performance of all of them!), whereas Carpinteri provides good solutions at the crack surface; (iii) when three parameters such as such as the relative crack depth ( a / D ), the crack aspect ratio ( a/b ) and the position at the crack front ( x/h ) are required, then the solutions by Shin and Cai are recommended (although they do not work as well as that of Astiz), and in addition they are the only which distinguish between free ends and constrained end in the analysis. 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