Simple Modeling and Strength Evaluation Methods for Bolt Joints Using Shell Elements and Beam Elements (1st Report, Modelling Method)

Abstract

The stiffness of an engineering structure with joints depends not only on the materials and dimensions of the structure but also on the stiffness of the fasteners that connect its components. To evaluate the mechanical behavior of a complex structure with bolted joints, it is important to develop a simple finite element (FE) modeling technique that accounts for the effect of the joint on stiffness. In this study, we developed a modeling technique that simplifies the bolt-jointed structure by using shell and beam elements. The stiffness of the beam element was related to the stiffness of the jointed plates and bolt. We set the equivalent pressure area on the bearing surface region, and the nodes in the equivalent pressure area were connected to the beam element as rigid region by using constraint equations. We measured the eigenvalues of test pieces and calculated those by FE analysis. The analytical eigenvalues agreed well with the experimental results. By using this modeling method of bolt joint, we can evaluate the supporting force of each bolt in the any structure with a large quantities of bolt joints.