System to increase the tension capacity of pipe piles driven into the ocean floor

摘要

A new pile assembly and process are disclosed. A pile cap is attached to a pipe pile. A partition is installed below the pile cap creating an air chamber between them that is at surface atmospheric air pressure. An external conduit containing a valve that is closed connects the pile's interiors above and below the partition. The pile is driven into the ocean floor filled with entrapped sea water below the partition so that little or no soil core is generated. After the clay soils adjacent to the pile have regained their strength, the valve is opened. A small amount of sea water expands into the air chamber. The pressure on both sides of the partition and the bottom of the pile cap is now slightly above surface atmospheric air pressure. It is the downward force of hydrostatic pressure on top of the pile cap that increases the tension capacity of the driven pile. In deep water hydrostatic pressure is substantial, constant and cheap.