Patent ID: 8157481

Claim:
A method of installing a foundation system on the ocean floor to accept tendons for a tension leg platform, comprising: installing a plurality of pile members into an array of pile clusters through independent freestanding operations, wherein installing said plurality of pile members comprises, for each pile member: lowering the pile member end first into contact with the ocean floor to setdown in a preselected position; further lowering the pile member through a first interval at a controlled rate of self penetration advancing under the weight of the pile member, guided only by setdown and orientation controlled by rate of feed that does not exceed the rate of penetration in this first interval; further lowering the pile member through a second interval of self penetration advancing under the weight of the pile member during which the pile is self-guiding; and driving the pile member through a third interval to a point at which the pile is secure for the design load; and providing a plurality of tendon receptacles, each presented on the top end of a pile member to concentrically receive a single tendon and providing a load path axially aligned with the pile member wherein providing the tendon receptacles comprises: providing tendon receptacles formed integrally with pile members and with an interior load shoulder positioned below a tendon load connection; and wherein driving the pile member comprises: inserting an internal follower into the tendon receptacle and in contact with the internal load shoulder; attaching an underwater hammer to the internal follower; driving the pile member into the ocean floor by hydraulically driving the underwater hammer to strike the internal follower whereby the direct force of the hammer blows bypasses the tendon load connection.