The influence of in-plane constraints on fatigue crack growth rate

The geometry of structural members can influence the fatigue crack growth rate. The influence can be taken into account by incorporating dimensions in the formulas. However, such an approach is ineffective as the dependence of the crack growth rate is hard to predict and the formulas depend on the shape of the element. For each shape, a new formula is required. It is, however, possible to use another approach that can be called a local approach in which parameters of the stress field in the neighbourhood of the crack tip can be utilized. It can be considered as the extension of Paris' approach to fatigue crack growth. In the paper, the T-stress depending on the element's geometry is used to quantify the effect of geometry on the fatigue crack growth rate. A series of fatigue tests on three-point bending specimens with different initial crack lengths were conducted. As a result, the dependence of the crack growth rate on the T-stress value was obtained.

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Opracowanie rekordu ze środków MNiSW, umowa nr POPUL/SP/0154/2024/02 w ramach programu "Społeczna odpowiedzialność nauki II" - moduł: Popularyzacja nauki (2025).