Titel short: Ultimate Strength of a large WT-blade The present work contains a study of the structural static strength of wind turbine blades. A combination of experimental and numerical work has been used to address the most critical failure mechanims and to get an understanding of the complex structural behaviour of wind turbine blades. Four failure mechanisms observed during the full-scale tests and the corresponding FE-analysis are presented. Elastic mechanisms associated with failure, such as buckling, localized bending and the Brazier effect, are studied. In the thesis six different...