ABSTRACT
Intermediate foundation installation and in-place response (resistance and stiffness) both need to be considered, usually concurrently. Intermediate anchor resistance in normally consolidated clay is a function of time after installation, while an appropriate Factor of Safety on in-place resistance has to be assigned a priori in order to determine the foundation geometry. Design requires simultaneous input from geotechnical and structural engineers. These aspects of intermediate foundation design differ from those normally used to design shallow or deep pile offshore foundations. Intermediate foundations must be installed to their design penetration below seafloor. For intermediate support foundations, this ensures sufficient in-place resistance to withstand combined vertical, horizontal, moment and twist (VHMT) loads. Unlike piles, proof of sufficient V resistance during installation is not necessarily proof of sufficient resistance under VHMT loads.
