FOUNDATION DESIGN FOR DEEPWATER GRAVITY BASE STRUCTURE WITH LONG SKIRTS ON SOFT SOILS

The Gullfaks C structure when installed in 1989 will have extended North Sea substructure technology on many frontiers, e.g. deepest water, heaviest concrete base, and greatest environmental loadings, on a site with multilayered soft and geotechnically complex soil conditions. The paper reviews some of the geotechnical aspects related to the novel engineering solutions used, particularly the 22m long concrete diaphragm skirts that have requires extensive in situ field tests and laboratory investigations together with advanced foundation analysis. This paper includes a comparison and discussion of results from foundation stability analysis and comments on load transfer and contained highly stresses zones.