Impact of nonlinearity on bolt forces in multi-bolted joints: A case of the assembly stage

Abstract

This study concerns modeling, computation, and analysis of multi-bolted joints in the assembly stage. The physical joint model is introduced as the assembly of the following three basic subsystems: a set of fasteners (bolts), a flexible joined flange, and a contact layer between it and a rigid support. The Finite Element Method (FEM) was used for modeling. Bolts were replaced by the bolt models of the spider type. The joined flange was modeled with spatial finite elements. As a model of the contact layer, the Winkler contact layer model was adopted. The truth of the theorem was tested, according to which nonlinear characteristics of the contact layer might have an insignificant impact on the final computational values of bolt preloads in the case of sequential tightening of the joint. The results of the calculations for the selected multi-bolted joint are given and compared with the experimental results. Conclusions of paramount importance to the engineering practice are comprised.