Failure Investigation of the Wind Turbine Blade Root Bolt

摘要

The failure analysis of the high-strength bolt at root position of the wind turbine blade was conducted to find the cause of fracture. Detailed investigations using several characterization techniques such as stress calculation, chemical composition test, mechanical property test, metallurgical investigation, and fractography analysis were performed to identify the cause of the bolt failure. Based on the theoretical calculation and failure analysis, it could be concluded that the bolt failed by fatigue accelerated by stress concentration while under low temperature. Practical suggestions were also given to avoid similar failures.