CPT correlation developed from numerical analysis to predict jack-up foundation penetration into sand overlying clay

Rapid uncontrolled leg penetration, or punch-through, accounts for a substantial number of accidents related to jack-up platforms, which are typically only employed at any one site for a few months before being removed and installed elsewhere. Hence, the ability to predict the load–penetration curve of a spudcan footing is particularly important in layered soil profiles, in order to identify punch-through risk prior to mobilisation of the rig. The correlation method proposed here links the spudcan load–penetration curve directly to the profile of cone tip resistance that is typically obtained as part of an offshore site investigation campaign. This contrasts with existing approaches that require input parameters that are empirically derived from site investigation measurements or necessitate additional soil element testing in an onshore laboratory.