Stress analysis of simple tubular joints - Loaded chord members

Abstract

This thesis covered the subject of stress analysis in simple tubular joints, with a focus on tubular joints with loaded chord members. The type of loading investigated is even though quite common, not very much investigated. This is referring to local loads on joints that may come from minor sources such as installation of mechanical clamps around the local area of joints. This type of loading can have an effect on the overall fatigue performance of the joints and by extension the structures in which they are present. Finite element analysis with shell elements was used a tool to investigate stress concentration in such joints. Chord loading was defined as a distributed circumferential vertical load at defined distance away from chord crown positions. Stress concentration factors and where relevant, fatigue life(s) where determined using both FEA and parametric equations from DNV-RP-C203. For some of the joints, FEA results were directly compared to results from standard, while for other joints, results from standard were only used as a reference point for FEA results. For the tubular joints with loaded chord members, focus was mainly on finding stress concentration factors on the chord side of the joint intersection.i.e the crown and saddle positions of the chord.