On the compatibility conditions for modeling tubular joints using different types of elements

Abstract

It has been a common practice to model an offshore tubular joint using three-dimensional brick elements for the brace/chord intersection region, including the weldment, and shell elements for the rest of the joint, instead of using only three-dimensional brick elements. This is to ensure that the model size is manageable for performing parametric studies. However, it is an extremely tedious procedure to implement the necessary and sufficient compatibility conditions at all nodes lying on the interface between brick and shell elements. An investigation has been carried out to examine the effects of partial relaxation of compatibility conditions on the location and magnitude of hot spot stresses at the brace/chord intersection. Results obtained have shown that, as long as the compatibility conditions at the shell loof nodes were implemented, the hot spot stresses obtained would be reasonably accurate. It was also found that using three or more rows of brick elements after the weld toe will ensure better accuracy of results. Copyright © 1996 Published by Elsevier Science Ltd.