Free-sliding seabed mudmat foundation

A free-sliding seabed mudmat foundation, comprising:

• a base foundation siting on a seabed to support dead weights of the free-sliding seabed mudmat foundation and a subsea infrastructure;
• an upper foundation siting and sliding in an inner space of the base foundation;
• and
• a cover plate fixed on a top of the base foundation;
• said base foundation mainly comprises a base plate, a plurality of lateral baffles, and a plurality of skirts;
• the skirts are symmetrically attached to a bottom of the base plate to enhance a rigidity of the base plate, and are inserted in the seabed to improve a horizontal anti-sliding resistance and a vertical bearing capacity of the free-sliding seabed mudmat foundation;
• the lateral baffles are fixed around the base plate to form an open hexahedral space, and a top of the lateral baffles further has a plurality of screw holes to fix the cover plate;
• said upper foundation further comprises an upper plate, a plurality of stop blocks, and a plurality of universal rolling ball bearings;
• the upper plate is configured with a plurality of springs around the upper plate and is configured with a plurality of dowel holes on the upper plate, and the upper plate has a size smaller than a size of the open hexahedral space formed by the lateral baffles and the base plate;
• the springs are connected between an inner side of the lateral baffle and a lateral side of the upper plate;
• the stop blocks are fixed on four corners of an upper surface of the upper plate to limit a rotation movement of the upper foundation;
• the universal rolling ball bearings are fixed on a bottom of the upper plate and sit on an upper surface of the base plate;
• the subsea infrastructure is configured on the upper surface of the upper plate to connect an end of a pipeline to transport oil;
• a horizontal push force acts on the upper plate generated by the pipeline due to heating and pressurization during operation, causing the upper plate to slide on the base plate through the universal rolling ball bearings, and to release a axial force on the pipeline due to heating and pressurization;
• said cover plate further comprises a flat plate with a mid-hole, allowing the subsea infrastructure and the pipeline to extend through the mid-hole, and a plurality of eyebolts configured on an upper surface of the flat plate for installation and recovery of the free-sliding seabed mudmat foundation;
• the flat plate further has a plurality of screw holes to match the screw holes on the top of the lateral baffles, and to fix the flat plate to the lateral baffles;
• and the flat plate further has a plurality of dowel holes to match the dowel holes on the upper plate, and to fix the upper foundation to the cover plate through dowel pins.