Issue 49

S. Seitl et alii, Frattura ed Integrità Strutturale, 49 (2019) 97-106; DOI: 10.3221/IGF-ESIS.49.10

Focused on Crack Tip Fields

Approximation of the crack-tip field in fatigue cracks in bridge steel specimens: DIC analysis of different constraint levels S. Seitl, P. Miarka Academy of Sciences of the Czech Republic, Institute of Physics of Materials, v. v. i., Žižkova 22, 616 62 Brno, Czech Republic and Brno University of Technology, Faculty of Civil Engineering, Institute of Structural Mechanics, Veveří 331/95, 602 00 Brno, Czech Republic seitl@ipm.cz, http://orcid.org/0000-0002-4953-4324 Petr.miarka@vut.cz http://orcid.org/0000-0002-4953-4324 V. Růžička, L. Malíková, Brno University of Technology, Faculty of Civil Engineering, Institute of Structural Mechanics, Veveří 331/95, 602 00 Brno, Czech Republic ruzicka@musicer.net, https://orcid.org/0000-0002-1954-6340 malikova.l@fce.vutbr.cz, http://orcid.org/0000-0001-5868-5717 A. S. Cruces, P. Lopez-Crespo Department of Civil and Materials Engineering , University of Malaga, C/Dr Ortiz Ramos s/n, 29071 Malaga, Spain ascruces@uma.es plopezcrespo@uma.es , https://orcid.org/0000-0002-5897-5615

A BSTRACT . A study on the accuracy of the approximation of the displacement field around of crack tip in a sample made from bridge steel (S355) is main objective of contribution. Linear elastic fracture mechanics (LEFM) theory in framework of multi-parameter formulation, i.e. postulated by Williams is used to determine of coefficients of Williams power series terms. Over deterministic method was used to calculate the terms based on the least squares regression technique, applied on data from numerical simulation and experiment on S355 steel grades. Comparison between the stress fields (by principal stress  1 and von Mises stress  HMH ) obtain from experimental measurement DIC, Hybrid method and obtain from reconstruction by using various number of Williams power terms are quantified in order to get key information around the crack tip region on bridge steel specimens. K EYWORDS . Displacement; Crack-tip stress fields; DIC; High order terms; Multi-parameter approximation accuracy; Williams power series.

Citation: Seitl, S., Miarka, P., Ruzicka, V., Malikova, L., Cruces, AS. Lopez-Crespo, P. Approximation of the crack-tip field in fatigue cracks in bridge steel specimens: DIC analysis of different constraint levels, Frattura ed Integrità Strutturale, 49 (2019) 97-106.

Received: 16.05.2019 Accepted: 22.05.2019 Published: 01.07.2019

Copyright: © 2019 This is an open access article under the terms of the CC-BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

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