Predicted and observed settlements of a subsea rock installation : comparison between field measurements and FE simulations of soft North Sea clay

Abstract

In this paper, a study is presented on the possibility to numerically simulate observed settlements of an offshore subsea rock foundation installed on normally consolidated clay. Settlements were monitored at 31 days and 200 days after installation and compared against predictions computed by means of finite element analysis. The results highlight that computations with a material model incorporating a logarithmic stress-strain relationship can accurately predict the consolidation settlements of normally consolidated clay. For long-term settlements, a material model that includes a creep factor is likely to increase the prediction accuracy of the total settlements. This study was performed in order to improve the prediction of soft clay settlements, as this phenomenon may have a large impact on design for sensitive subsea infrastructure installed on the seabedGodkänd; 2015; 20150605 (hmat