Modelling of riveted joints with a new rivet element

Riveting is a well established technology in the manufacturing of aeronautical structures as well as in the automotive industries. Despite its simplicity, the rivet presents a local stiffness that is not easy to properly model within a large finite element analysis. However, precision in the local stiffness evaluation is essential to perform any structural analysis when several rivet are applied in a joint structure. The result is that any rivet requires a local mesh refinement or, and this is the most common case, a drastic simplification of its structural modelling characteristics. In the present paper the structural behavior of a riveted lap joint connection was investigated experimentally and numerically using a new rivet finite element. The Rivet Element, based on a closed-form solution of a theoretical model of the rivet joint, is able to precisely evaluate, in FE analysis, both local and overall stiffness of riveted joints with a very low contribution of dofs. A comparison with a joint model performed with very refined non-linear 3D model of rivet and with experimental data is performed and a good agreement is demonstrated.