Modelling of the fatigue strength degradation due to a semi-elliptical flaw

•The performances of surface flaws are evaluated through a computational strategy under cyclic loading.•Driving mode analysis, performed via novel analytical solutions, is verified using experimental observations.•Through the fatigue life and crack path evaluations the crack shape effect is examined. Due to the fulfilment of modern operational requirements and time-consuming of complex fatigue responses computation, the surface micro-flaw analysis in large moving systems is still one of the challenging tasks. Thus, the present research work discusses the fatigue computational design strategy that can be used to properly evaluate the driving mode caused by a surface semi-elliptical flaw. Further, through the novel analytical solutions, experimentally assessed, the residual life and crack path are designed taking into account the crack shape effect.