Prediction of Punch-through during spudcan installation in complex soil profiles

Due to the prevalence of complex soil conditions, punch-through incident occurs frequently during the installation of jack-up rigs. Therefore, a great number of studies have recently been carried out to develop new design approaches for predicting punch-through during spudcan penetration in complex soil profiles. The experimental and numerical techniques adopted in these studies are briefly introduced here, followed by a summary of the design approaches developed in these studies and those suggested by the current design guidelines ISO 19905-1. The advantages and disadvantages of the summarized design approaches are discussed, in particular for typical soil profiles encountered in the offshore fields including sand-over-clay, stiff-soft-stiff clay, soft-stiff-soft clay, clay-sand-clay, and clay-sand-clay-strong layer. The performances of the ISO-suggested approaches and the new approaches are compared through the prediction of centrifuge model tests, with the new approaches showing more reasonable and accurate agreement with the measured data.