Effect of Manufacturing Tolerances on the Number of Load Carrying Fasteners in a Joint Subjected to a Shear Load: A Statistical Approach

Within the elastic range, the number of load-carrying fasteners in an interchangeable manufactured joint subjected to a shear load is dependent upon the following characteristics: 1. Material properties of the constituent parts in the shear joint. 2. Geometry of the shear joint. 3. Manufacturing tolerances of the constituent parts in the shear joint. 4. Number of fasteners in the shear joint. 5. Preload on the fasteners in the joint. 6. Static coefficient of friction between the joint surfaces. Neglecting the effects of preload and friction, the number of load-carrying fasteners is determined for a theoretical bolted joint design as a function of the remaining four (above) parameters. The analysis is accomplished by assuming all deformation in the constituent parts of the joint remain within the elastic range and then examining the stress-strain relationship existent in the shear joint. Based on simplifying assumptions, the total deflection is calculated and then, statistics are applied to the manufacturing tolerances of the constituent parts of the shear joint. The results suggest that plastic deformation occurs in all classically designed shear joints and the predicted number of load carrying fasteners using this analysis approach is in error. Suggestions for future research are presented