Abstract:Aiming at problems of fatigue damage of bolted connections during services, the influences of plate thickness and connection gap were investigated via the combination of theoretical, numerical and experimental methods. Numerical results indicated that there was stress concentration by the bolt holes of aluminum plates because of the existence of geometry incontinuity and the connection gap. Under cyclic loads, fatigue cracks were easily to be initiated near these holes, leading to the damage and fracture of components. However, the loading conditions around the holes can be improved through the frictional effects induced by the application of bolt load. Based on static analysis, the detail fatigue rating (DFR) values were calculated according to the theory of the doubleshear joint with loadtransmitting fastener structures. The estimated values were consistent with experimental results derived from the twopoint method and the relative differences were within 10%. This implied that the theoretical method had good engineering applicability. Results showed that the connection gap would affect the load of bolted connectors. There can be a large stress concentration at the bolt that first contacts the plate during the stretching process, which would eventually lead to the fatigue failure of the component. Furthermore, the increment of thickness would cause additional bending moment that could affect the stress distribution at the edge of the hole and diminish the fatigue performance of components. In this case, the effects of plates thickness and connection gap can be comprehensively embodied through stress concentration factors. The increment of stress concentration factors would approximately lead to the linear diminution of components’ DFR values. As a result, this work can provide references for further investigation of fatigue performances of bolted connection structures.