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The beginning of the fatigue crack growth of so-called long cracks isdefined by the threshold value of the material. For the determination of the thresholdvalues different standards, e.g. ASTM E 647, are available. In these standards loadsheddingmethods are proposed with an exponential decrease of the load. The slope isdefined as follows: CASTM = (1/K)(dK/da)  -0,08mm-1. The R-ratio is kept constantduring the whole experiment. However, the initial value of the stress intensity factorKmax,0 is not specified. Within the scope of this paper the influence of Kmax,0 as well as alinear decrease of the force is investigated. Moreover the influence of the slope C isanalysed using different materials. For the investigation of the crack initiation SNcurvesare determined with notched and cracked specimen for different loadingsituations.