Removable mudmat and method of use on soft floor

DETAILED DESCRIPTION The disclosed invention overcomes much of the expense involved in the removal of mudmats by providing a mudmat design and removal procedure which, in combination with a particular jacket design, eliminates the need for cutting the mudmat into pieces and eliminates the need for pulling said mudmat pieces horizontally prior to pulling them vertically off the seafloor.
The invention provides a removable mudmat for supporting a jacket on a soft, unconsolidated seafloor during installation of said jacket to the seafloor.
The mudmat comprises a bearing plate, framing members which are attached to and provide support for said bearing plate and means for removably attaching the framing members to the jacket.
The invention further provides a method of supporting a jacket on a soft, unconsolidated seafloor during installation of said jacket to the seafloor.
The method comprises the steps of attaching at least one mudmat to said jacket prior to the installation of the jacket to the seafloor, detaching said mudmat from the jacket after the installation of the jacket, attaching at least one lifting cable to the mudmat, and lifting the entire mudmat off the seafloor in one piece by pulling generally vertically on the lifting cable.
The invention is designed to be used in combination with a jacket having 1 center pile sleeve and 4 corner pile sleeves, and in which 2 adjacent corner pile sleeves define one side of the jacket, 2 sides of the jacket having jacket legs interposed between the adjacent corner pile sleeves and the other 2 sides of the jacket having horizontal-diagonal members running inwardly from the corner pile sleeves toward the center of the jacket, said horizontal-diagonal members intersecting each other.