• carbon fiber
• compositi
• danno
• delaminazione
• fibra di carbonio
• giunzioni chiodate
• risultati sperimentali

Bolted joints are widely used in the aerospace industry but often represent a critical area of initiation of damage, especially on composite parts. End-life inspections performed on several aircraft, found multiple instances of delamination damage initiation around the bolt holes of pin-loaded joints on carbon/epoxy composite structural panels. To investigate the severity of such damage and the conditions in which it can bring to dangerous failure, a research program will perform single and double-lap bolted joints tests using special composite specimen in which controlled and consistent delamination has been introduced around the hole location. At present time, however, there is no standard procedure to safely introduce such damage in a composite specimen. This thesis presents a research program with the aim of defining the best method to introduce a controlled and consistent delamination damage on a carbon/epoxy composite specimen with a countersunk hole. Several methods have been proposed and analyzed in detail using Finite Element simulations and experimental activity.