Issue 39

S. Seitl et alii, Frattura ed Integrità Strutturale, 39 (2017) 110-117; DOI: 10.3221/IGF-ESIS.39.12 110 Focussed on Modelling in Mechanics Fatigue crack behaviour: comparing three-point bend test and wedge splitting test data on vibrated concrete using Paris' law S. Seitl Institute of Physics of Materials, Academy of Sciences of the Czech Republic, Zizkova 22, 616 62 Brno, and Brno University of Technology, Faculty of Civil Engineering, Veveří 331/95, Brno 602 00, Czech Republic seitl@ipm.cz , http://orcid.org/0000-0002-4953-4324 T. Thienpont Ghent University, Faculty of Engineering and Architecture, Valentin Vaerwyckweg 1, 9000 Ghent, Belgium and Brno University of Technology, Faculty of Civil Engineering, Veveří 331/95, Brno 602 00, Czech Republic W. De Corte Ghent University, Department of Structural Engineering, Faculty of Engineering and Architecture, Valentin Vaerwyckweg 1, 9000 Ghent, Belgium A BSTRACT . The fatigue behaviour of concrete has become more important for the design of constructions due to the desire to build slimmer structures, which are more sensitive to fatigue loading. This article aims to evaluate and compare the fatigue crack propagation rate in vibrated concrete for four different stress ratios using the Paris-Erdogan law. The data evaluation in this article is based on crack mouth opening displacement (CMOD) measurements from cyclic three-point bending tests on single edge notched beams and from wedge splitting tests on notched cubes, obtained from experiments at Ghent University. For this study, finite element analysis is used to obtain a mathematical relationship between the CMOD and the relative crack length a/W, as well as a relationship between the stress intensity ratio ∆K and a/W. The obtained mathematical relationships were then combined with the measured CMOD values to correlate the test data to the Paris- Erdogan law. Herein, the crack propagation rate da/dN is plotted against the corresponding stress intensity range ∆K in a log-log graph. In a final step, the Paris-Erdogan law parameters C and m were obtained through linear curve fitting on the data points from the obtained graphs. The parameters C and m are then used to compare and evaluate the fatigue crack behavior in vibrated Citation: Seitl, S., Thienpont, T., De Corte, W., Fatigue crack behaviour: comparing three- point bend test and wedge splitting test data on vibrated concrete using Paris' law, Frattura ed Integrità Strutturale, 39 (2017) 110-117. Received: 11.07.2016 Accepted: 02.09.2016 Published: 01.01.2017 Copyright: © 2017 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.