International Journal of Fracture

, Volume 187, Issue 2, pp 285–291 | Cite as

Cracks at rounded V-notch tips: an analytical expression for the stress intensity factor

  • A. Sapora
  • P. Cornetti
  • A. Carpinteri
Brief Note


An analytical expression for the stress intensity factor related to a crack stemming from a blunted V-notch tip is put forward. The analysis is limited to mode I loading conditions, as long as the crack length is sufficiently small with respect to the notch depth. The proposed formula improves significantly the predictions of a recently introduced relationship, by considering a notch amplitude dependent parameter. Its values are estimated through a finite element analysis: different notch amplitudes, ranging from \(0^{\circ }\) to \(180^{\circ }\), and different crack length to root radius ratios, ranging from 0 to 10, are taken into account. The evaluation of the apparent generalized fracture toughness according to equivalent linear elastic fracture mechanics concludes the paper.


Brittle fracture Blunted notches  Mode I SIF 



Authors wish to thank prof. Lazzarin for useful discussions on the present topic. Furthermore, the support from the Italian Ministry of Education, University and Research of the Project FIRB 2010 Future in Research Structural Mechanics Models for Renewable Energy Applications (RBFR107AKG) is gratefully acknowledged.


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Copyright information

© Springer Science+Business Media Dordrecht 2014

Authors and Affiliations

  1. 1.Department of Structural, Geotechnical and Building EngineeringPolitecnico di TorinoTurinItaly

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