Abstract
In literature, a wide range of conceptual models are used to investigate bolt-nut connections using the finite element method (FEM). This is especially true for 2D analyses; however, the sensitivity of the results with respect to subtle differences have not always been made clear, resulting in a lack of consistency between models. In this article, a range of models for simulating a 2D bolt-nut system are developed using the FEM software ABAQUS and a parametric study is conducted. Different thread-root radii, the inclusion of plasticity and various methods for constraining the nut are modelled and compared with a reference case. By creating a consistent and common simulation methodology as a base case, model features incurring the most significant change in results were ascertained; and conversely, highlighting parameters that can be changed to little effect. For a 2D model, the thread load distribution and stress-concentration are very sensitive to how the nut is constrained, whilst the inclusion of plasticity results in a more uniform load distribution. Varying the root radius significantly affects the stress-concentration; but its effect on the load distribution is marginal, in turn, it follows that small flaws and cracks would not significantly change the thread load distribution. The relative importance of a given parametric change or assumption in the simulation is shown.