applied fracture mechanics

226Applied Fracture MechanicsThe proposed modification of the LSM criterion offers better fit of results of the test dataapproximation (unachievable with the classical LSM method). These effects are as follows:- the provision of equal “weights” of each of the test data points in the total sum thatdetermines this criterion (i.e. the sum of differences between approximated andapproximating values) – independently of the magnitude of difference between valuesof data subject to approximation and that of difference between the approximated andapproximating values,- high effectiveness while approximating single, several, as well as a great number ofsets/curves of test data,- it becomes even more precise as the test data from the same (research-testing) groupsshow smaller scatter,- may be used in other analyses of the same type related with test data regression, since itoffers an all-purpose approach not related to propagation curves da/dN-K.Author detailsSylwester KłyszAir Force Institute of Technology, Warsaw, PolandUniversity of Warmia and Mazury in Olsztyn, PolandAndrzej LeskiAir Force Institute of Technology, Warsaw, Poland5. ReferencesAFGROW Users Guide And Technical Manual. (2002). AFRL-VA-WP-TR-2002-XXXX,Version 4.0005.12.10, James A. Harter, Air Vehicles Directorate, Air Force ResearchLaboratory, WPAFB OH 45433-7542ASTM E647 Standard test method for measurement of fatigue crack growth ratesBukowski, L. & Kłysz, S. (2003). Compliance curve for single-edge notch specimen.Zagadnienia Eksploatacji Maszyn, No. 2(134), pp. 95-104Elber, W. (1970). Fatigue crack closure under cyclic tension, Eng. Fracture Mechs., Vol.2, pp.37-45Forman, R.G.; Kearney, V.E. & Engle, R.M. (1967). Numerical analysis of crack propagationin cyclic loaded structures, J. Bas. Engng, Vol.89, pp. 459-464Forman, R.G.; Shivakumar, V.; Cardinal, J.W.; Williams, L.C. & McKeighan, P.C. (2005).Fatigue crack growth database for damage tolerance analysis, DOT/FAA/AR-05/15, U.S.Dep. of Transportation, FAA Office of Aviation Research, Washington, DC 20591Fuchs, H.O. & Stephens, R.I. (1980). Metal fatigue in engineering, A Willey-IntersciencePublicationHuang, X.P.; Cui, W.C. & Leng, J.X. (2005). A model of fatigue crack growth under variousload spectra, Proc. of 7th Int. Conf. of MESO, Montreal, Canada, pp. 303–308