Finite element analyses of spudcan - subsea template interaction during jack-up rig installation

摘要

During the penetration of spudcans, the soil might undergo large deformations, which are often difficult to model using a conventional large deformation Finite Element (FE) formulation due to severe distortion of elements. This paper presents the application of two finite element modelling approaches, namely the Press-Replace (PR) technique (a small strain geometry update procedure), which was introduced to promote modelling installation process among practical engineers, and the Coupled Eulerian-Lagrangian (CEL) technique, which can handle very large deformations such as the deformations experienced by the soils under a penetrating spudcan. Using both methods, the penetration of a spudcan is analysed to investigate the effect of potential tilting of the template structure due to the large volume of soil displaced: first without the subsea template and secondly, considering the subsea template in the vicinity to consider the interaction effect. The calculated surface heaves, using both methods, are compared with site measurements.