New analytical model of bolted joints

The conventional theory of bolted joints adopts equivalent cylinders, cones or spheres for compression members. In this model, the member deformation is determined by the member stiffness that remains unchanged whether the external load is present. In fact, the external load causes an additional member deformation that is not determined by the member stiffness measured at pre-load. The external load also causes a member rotation which not only reduces the member stiffness, but also delays the separation of the joint. Based on these observations, a new model of bolted joints is developed. Finite element analyses is performed to verify the proposed model.