The use of circular steel flange plates with circular bolts pattern connections is common in tubular structures
used in different applications such as transmission and communication structures. Several published literatures
include methods for the design of these connections under tension loads. These methods are not widely used in
the industry as they are either complex or yielding results that are not always consistent with published test data.
Therefore, there is still a need for a simplified, yet accurate, method for designing these connections when
subjected to tension loads.
This paper presents a numerical study performed on circular flanged connections subjected to concentric axial
tension loads. The analysis part of the study is conducted using the Finite Element (FE) package ADINA
considering one common geometrical flange plate configuration, ring configuration, while considering contact
surface separation. The results obtained from the FE analyses are compared with published experimental data
from which it is concluded that the FE model can predict the behaviour of these connections with a high degree
of accuracy.
Parametric investigation is then conducted to numerically expand the experimental data to gain more insight
into the behaviour of these flange plate connections and to use this data later in this work to validate the proposed
design method. The varying parameters considered in the numerical investigation include base plate
thickness; number of bolts; bolt circle diameter and plate diameter.
A simple design approach based on yield line theory is then introduced and a comparison between yield loads
predicted using the proposed model and the finite element results is presented. The yield loads resulting from
proposed design method show good agreement with the finite element results with 10% maximum difference. |