Bolted Joints Modeling Techniques, Analytical, Stochastic and FEA Comparison

Abstract

Bolted joints Design analyses are in general, very complex and it is very difficult to find a single technique to study the complete behavior of the bolted joints. The most popular analytical method is the well-known VDI 2230 which addresses most of the cases very well. This analytical method uses extreme values for critical parameter variations and is considered to be conservative, but the quickest method. Stochastic analysis is a more advanced method where variations in critical parameters are modeled as statistical distributions and Monte Carlo simulations allow predicting the behaviors of bolted joints through selective parameter variations. Finite element analysis of bolted joints is another methodology to analyze complex bolted joint designs. Though advances in FE modeling techniques help to model bolted joints more accurately, different failure modes require different modeling techniques. For practical complex bolted joints design analysis, a hybrid of analytical and different FEA models is needed for a full analysis; but a combination of FEA techniques can be used to study any bolted joint in detail for all the failure modes. Hence, it is important to study and understand the limitations of each of the modeling techniques. This paper looks at analytical and stochastic methods of bolted joints as well as three different FEA methods — 3D, Axisymmetric and Beam & Rigid Spider — to study different failure modes. Parametric (DOE) FEA simulation technique for variation parameters bolted joint behavior prediction was investigated; this paper examined the DOE parameter of coefficient of friction. A general case study is used as benchmark for comparison between the techniques and to quantify the advantages and disadvantages of each method.