Static and Fatigue Testing of Thick Adhesive Joints for Wind Turbine Blades

Abstract

Experimental results are presented for the static and fatigue strengths of thick adhesive joint specimens which are representative of blade joints. Four closely related geometries are explored, with over 250 individual tests; fatigue loading conditions include both tension and reversed loading. The four geometries are compared as to static strength statistics and fatigue lifetime trends. Crack origins and crack growth modes are described for each case, along with typical flaws related to the lower strength specimens. Finite element analysis is used to explore interactions between joint geometry, local stress concentrations and pore locations.