PSI - Issue 2_A

8

C. Ruggieri and R. H. Dodds / Structural Integrity Procedia 00 (2016) 000–000

Claudio Ruggieri et al. / Procedia Structural Integrity 2 (2016) 1577–1584

1584

5. Concluding Remarks

This study describes a probabilistic framework based on a modified Weibull stress model to predict the e ff ects of constraint loss and plastic strain on macroscopic measures of cleavage fracture toughness applicable to fracture spec imens and crack configurations tested in the ductile-to-brittle transition region. Application of the modified Weibull stress methodology predicts accurately well the distribution of fracture toughness, J c , for an A515 Gr 65 pressure vessel steel tested in the ductile-to-brittle transition region. Overall, the analyses conducted in the present work show that the modified Weibull stress approach based on the simplified particle distribution model holds significant promise as an engineering procedure to multiscale predictions of fracture behavior in structural components with diverse range of crack-tip constraint.

Acknowledgments

This investigation is supported by Fundac¸a˜o de Amparo a` Pesquisa do Estado de Sa˜o Paulo (FAPESP) through Grant 2012 / 13053-2 and by the Brazilian Council for Scientific and Technological Development (CNPq) through Grants 473975 / 2012-2 and 306193 / 2013-2. The second author (RHD) was supported by the M.T. Geo ff rey Yeh Fund at the University of Illinois at Urbana-Champaign.

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