The Effect of Fastener Type on the Connection Performance of Bolted Joints in Composite Laminates

An experimental investigation was conducted to determine the effect of fastener type on the connection performance of double lap-type single bolted composite joints. The joints with blind bolts and high lock bolts were tested separately by static tests and dynamic tests. ASTM D 5961 was adopted by static tests, and tension-compression reversed force/stress ratio, R=-1, was selected to evaluate the fatigue tests. The appropriate levels of fatigue stress were determined by the ultimate bearing strength of the fastener structure obtained from the static tests. The bearing stress and the fatigue life (S-N) date of different fastener types of specimen were presented and the relationship between fastener types and fatigue life were obtained. The experimental results showed that the connection performance of the blind bolted joint was better than that of the high-locking bolted joint. The ultimate bearing strength of the blind bolted joints was 1.9% higher than that of the high lock bolted joints, and the fatigue life of the blind bolted joints was 1-2 orders of magnitude higher than that of the high-locking bolted joint under the same cyclic stress.