Effect of load transfer on the cracking behavior at a countersunk fastener hole

The objective of this paper is to describe the effect of fastener load transfer on the cracking behavior at countersunk fastener holes. Both experimental and computational studies are described and compared when possible. Fatigue failures at previously tested mechanical joint specimens were investigated and characterized. Qualitative three-dimensional finite element analyses revealed that the degree of load transfer through the fastener could influence the cracking behavior at the countersunk fastener hole. This finding from the qualitative analysis provides one good explanation to the experimental results of the mechanical joint specimens. The cracking location’s dependence on the load transfer can be attributed to the non-uniform bearing load distribution along the straight bore caused by the load transfer.