A new approach for evaluating fatigue lives of multi-fastener mechanical joints based on a nominal stress concept and minimal datasets. (November 2015) - Tian, B.J.
Highlights: New formula is derived to predict the nominal stress around the fastener hole. Modified method is developed to evaluate fatigue life of complex joint. Fatigue strength and life tests are conducted for three types of joints. Damage mechanisms were deduced from fractographies. The contrast verification of the modified method has been proven successfully. Abstract: New formulae are derived to predict the normal bypass, transfer and nominal stresses around the fastener holes on multi-fastener mechanical joints under plane stress conditions. A modified method based on the nominal stress concept is developed to evaluate fatigue lives of complex multi-fastener joints. The method is informed by fatigue characteristics of joints with similar structural details. Fatigue tests on two-rivet, four-rivet and eight-rivet joints were performed and damage mechanisms are deduced from fractographs. Good correlation is achieved between the predictions and actual experiments, demonstrating the practical and effective use of the proposed method.