Calculation of Stress Intensity Factors from Shell Elements under Mixed Mode Loading

Published on May 1, 2020in International Journal of Fatigue4.369
· DOI :10.1016/J.IJFATIGUE.2019.105447
Jan Kraft1
Estimated H-index: 1
(Technische Universität Darmstadt),
Carl Fällgren1
Estimated H-index: 1
(Technische Universität Darmstadt),
Michael Vormwald25
Estimated H-index: 25
(Technische Universität Darmstadt)
Abstract The strain energy release rate is calculated numerically for cracks in shells from shell elements by using the modified crack closure integral. This enables the separation of individual strain energy release rates for the different crack opening modes and the calculation of the corresponding stress intensity factors for mixed mode loading situations. The presented formulas are validated by comparing numerical results for a 3d finite element model with results computed from a plane shell model. These formulas are then used to calculate the stress intensity factors for thirteen crack configurations measured on a notched hollow cylinder under proportional cyclic loading.
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