This paper reviews the most important modelling techniques in the literature and proposes a new to study bonded patch repaired plates by including all known effects on the 1 fatigue crack growth rate. The modelling technique makes use of 2D plate finite elements and takes into account of adhesive failure as well as secondary bending due to the unsym-metrical configuration of single-sided patched plates. Comparisons between 3D models and 2D models were carried out to validate the 2D bending analysis and the calculated stress intensity factors. This new modelling technique was implemented in a computer code interfacing with the commercial FE package MSC NASTRAN and validated by published experimental tests for three different aluminium plates. Good agreements were obtained. The code was then used to conduct a parametric study on the geometry of the patch for two different substrate thicknesses showing that for a thinner substrate the life can be improved with a smaller patch. A tool to compute the most effective patch dimension for a prescribed fatigue life target has been developed.
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