ABSTRACT
The in-place resistance of intermediate foundations with low embedment ratios in sand is generally sensitive to seafloor scour. If scour is a potential problem, then scour protection is generally recommended as an alternative to regular seafloor/foundation inspections. Protection types include frond mats, rock fill, sandbags, or fences and diversion berms. If there is a significant time lag between foundation and scour protection installation, additional in-place analyses are normally performed of the unprotected foundation to verify that factored design loads do not exceed the factored soil resistance. Minimal-facilities hydrocarbons platforms normally require subsequent location of a jack-up rig to install well conductors. Similarly, offshore wind turbine monopiles or tripod substructures may be installed using a jack-up rig fitted with spudcans. A key issue is predicting lateral soil movements induced by the spudcan at the intermediate foundation. These movements have both horizontal and rotational components.
