A Novel Spudcan for Easing Spudcan-Footprint Interaction Issues

The interaction between a spudcan and an existing footprint is one of the major concerns during jack-up rig installation, especially in the surface clay layer. No guidance was provided in the recently finalised version of ISO guidelines 19905-1 [1] in regards to mitigating spudcan-footprint interaction issues except some proposed considerations due to the lack of detailed investigations. This paper reports a measure for easing spudcan-footprint interaction issues, with the efficiency of a novel spudan shape tested through 3D large deformation finite element (LDFE) analyses. The LDFE analyses using the Coupled Eulerian-Lagrangian (CEL) approach in the commercial finite element package ABAQUS. The soil conditions tested simulate soft seabed strength profiles close to the mudline. A critical reinstallation locations of 0.55D (D = spudcan diameter) and existing footprint depth (of 0.33D) were investigated. The main aim was to investigate if the spudcan shape itself can be used to mitigate potential footprint interaction when compared to a conventional spudcan. The results from this study indicated that the novel spudcan had the potential to ease spudcan-footprint interaction issues.