ICE 2009

Foundations to Precast Marine Structures

Precast concrete elements are increasingly used in the construction of Maritime Structures. They offer the prospect of efficient unit production and rapid construction, but that requires
the efficient construction of adequate foundation restraint. Foundation design and constructability for these elements is therefore a critical area, but little guidance is available on the
different forms of foundation available. Typical underwater foundation systems have been:

Pre-levelled Bed

  • Stone Layers

Base Infill

  • Tremie Concrete
  • Open Grouting
  • Grouted Fabric Formwork (Grout Bags)
  • Pumped sand

Weak / Inadequate Strata

  • Piled Foundations
  • Ground Improvement

This paper will describe these different foundation systems used underwater, and will describe particular experiences of combinations of systems used on completed and current projects.