Theoretical and numerical aspects of the volumetric approach for fatigue life prediction in notched components

Many macro-mechanical models for fatigue life prediction have been proposed. One of these methods is the 'volumetric approach'. This paper is a complete investigation in theoretical base, intrinsic features, assumptions and its applicability for various notched components. The macro-mechanical behavior of notch roots and special notch root characteristics in a bi-logarithmic diagram for fatigue crack opening stress corresponding to distance in notch root gives pseudo-fracture mechanics behavior for fatigue cracks in notch roots for specific regions. The effective stress, effective plastic zone and relative stress gradient are determined by means of elastic-plastic finite element analysis. The fatigue failure estimations have very good agreement with the experimental results for various kinds of notch geometry. (C) 2002 Elsevier Science Ltd. All rights reserved.