Issue 48

J. F. Barbosa et alii, Frattura ed Integrità Strutturale, 48 (2019) 400-410; DOI: 10.3221/IGF-ESIS.48.38 409 The logistic model allowed a better approximation to the experimental data in HCF region and a graphical analysis showed better results for a possible extrapolation of the analysis. The achieved results showed that the S-N curve formulation using the Logistic and Power Law equations obtained a better performance in the LCF and HCF regions and lower MSE values when compared to the generalized Power Law formulations and the ASTM E739 standard. It was also observed that the Logistic, Kohout-Věchet and Power Law equations are able to obtain smaller errors for the cases with a reduced number of experimental data. However, in order to generalize which model has a better fit, it is necessary to carry out an exhaustive study with a greater amount of experimental data of fatigue of other metallic materials. A CKNOWLEDGEMENTS his study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES) - Finance Code 001. The authors also acknowledge the Portuguese Science Foundation (FCT) for the financial support through the postdoctoral grant SFRH/BPD/107825/2015, as well as the funding of FiberBridge - Fatigue strengthening and assessment of railway metallic bridges using fiber-reinforced polymers (POCI-01-0145-FEDER- 030103) by FEDER funds through COMPETE2020 (POCI) and by national funds (PIDDAC) through Portuguese Science Foundation (FCT). R EFERENCES [1] ASTM Committee and others. (2004). Standard Practices for Statistical Analysis of Linear or Linearized Stress-Life (S- N) and Strain-Life (ε-N) Fatigue Data, ASTM Int. West Conshohocken, PA, USA. [2] ISO, B.S. (2012). 12107: 2003, Metallic materials--Fatigue testing--Statistical planning and analysis of data, Int. Organ. Stand. [3] Standard, E. (2003). Eurocode 3 : Design of steel structures, Part 1.9, Control, pp. 1–117. [4] BSI (British Standards Institution). (1980). Steel, concrete and composite bridges. 10: Code of practice for fatigue, Eurocode 3, (1). [5] Specifications, A.-L.B.D. (2004). American Association of State Highway and Transportation Officials (AASHTO), Washington, DC. [6] Kohout, J., Vechet, S. (2001). A new function for fatigue curves characterization and its multiple merits, Int. J. Fatigue, 23(2), pp. 175–83. [7] Weibull, W. (1961). Fatigue Testing and Analysis of Results: Publ. for and on Behalf of Advisory Group for Aeronautical Research and Development, North Atlantic Treaty Organisation, Pergamon Press. [8] Chaminda, S.S., Ohga, M., Dissanayake, R., Taniwaki, K. (2007). Different approaches for remaining fatigue life estimation of critical members in railway bridges, Steel Struct., 7, pp. 263–76. [9] Kajolli, R. (2013). A new approach for estimating fatigue life in offshore steel structures. University of Stavanger, Norway. [10] De Jesus, A.M.P., Pinto, H., Fernández-Canteli, A., Castillo, E., Correia, J.A.F.O. (2010). Fatigue assessment of a riveted shear splice based on a probabilistic model, Int. J. Fatigue, 32(2), pp. 453–62, DOI: 10.1016/J.IJFATIGUE.2009.09.004. [11] Jesus, A.M.P. de., Silva, A.L.L. da., Figueiredo, M. V., Correia, J.A.F.O., Ribeiro, A.S., Fernandes, A.A. (2011). Strain- life and crack propagation fatigue data from several Portuguese old metallic riveted bridges, Eng. Fail. Anal., 18(1), pp. 148–63, DOI: 10.1016/J.ENGFAILANAL.2010.08.016. [12] Correia, J., Apetre, N., Arcari, A., De Jesus, A., Muñiz-Calvente, M., Calçada, R., Berto, F., Fernández-Canteli, A. (2017). Generalized probabilistic model allowing for various fatigue damage variables, Int. J. Fatigue, 100, pp. 187–194. [13] Muniz-Calvente, M., de Jesus, A.M.., Correia, J.A.F.O., Fernández-Canteli, A. (2017). A methodology for probabilistic prediction of fatigue crack initiation taking into account the scale effect, Eng. Fract. Mech., 185, pp. 101–113, DOI: 10.1016/J.ENGFRACMECH.2017.04.014. [14] Kohout, J., Vechet, S. (2008). Some Estimations of Tolerance Bands of SN Curves, Mater. Sci., 14(3), pp. 202–205. [15] Zapletal, J., Věchet, S., Kohout, J., Obrtlík, K. (2008). Fatigue lifetime of ADI from ultimate tensile strength to permanent fatigue limit, Strength Mater., 40(1), pp. 32–35. [16] Mu, P.G., Wan, X.P., Zhao, M.Y. (2011). A New S-N Curve Model of Fiber Reinforced Plastic Composite, Key Eng. Mater., 462–463, pp. 484–8, DOI: 10.4028 /www.scientific.net/KEM.462-463.484. T