Abstract:
In this paper the results of a numerical study on the behaviour of
caisson foundations subjected to various combinations of loading are
presented. A typical caisson has been used in this study with a lengthto-
diameter ratio of 2. The caisson is assumed to be embedded in a
homogeneous soil deforming under undrained conditions. The
performance of the caisson under separate axial, lateral and torsional
forces was investigated first, followed by the interaction of these forces
with each other. The ultimate capacity of the caisson under combined
loading is presented in the form of failure envelope in the axialtorsional
loading plane and axial-lateral, and lateral-torsional loading
surfaces along the skirt of the foundation. It is shown that, although
lateral capacity of the caisson is dependent on the location of the
padeye, a unique normalised failure surface can be used to represent the
capacity of the caisson under all combinations of axial, lateral and
torsional loads regardless of the location of the padeye.
