A central pontoon semisubmersible floating platform for use in offshore
applications has a hull configuration including vertical support columns,
a central pontoon structure disposed inboard of the columns at a lower
end thereof, and a deck structure supported at an upper end of the
columns. The vertical columns and pontoon structure are constructed
substantially of flat plate. The vertical columns are adjoined to the
outer periphery of the central pontoon and have a transverse cross
sectional shape with a major axis oriented radially outward from a center
point of the hull, and a central vertical axis disposed a distance
outward from the pontoon outer periphery. Risers can be supported on the
inboard or outboard side of the pontoon and extended to the deck, and the
structure can be anchored by mooring lines extending along the outboard
face of the columns extending radially outward and downward from their
lower ends.