A foundation for an offshore structure is disclosed. The foundation includes a tower having an anchoring portion anchored in the seabed and a connecting portion arranged at the opposite end. The foundation also includes a power generation system arranged above the water surface connected to the connecting portion of the tower. A natural frequency of the offshore structure lies below an excitation component one times the rotational frequency 1P of at least one exciting component. The foundation also includes at least one restoring element connected to the tower via one or more transition pieces. The restoring element is designed such that, in a skewed position of the tower, tensile and/or compressive forces can be transferred to the tower by means of the restoring element such that the tower can be straightened up.

A plurality of seismic foundation frames are utilized to secure rebar in a fixed location to produce a cementitious supporting form that is embedded in the poured concrete and reinforces the concrete. The frame has an open construction with a plurality of openings to allow the concrete to flow therethrough and to provide increased surface area for reinforcement. The frame has pin openings and rebar openings for receiving and retaining pins or rebar respectively, such as when the frames are stacked. A frame has rebar retainers for retaining rebar that extends perpendicularly to the surface of the frame to a second frame at an offset distance. A flexible containment sleeve is configured around the frames and may be fastened to the frame to create a sleeved form for receiving a cementitious mix. The containment sleeve has apertures for controlled permeation to control the rate of cure of the cementitious mix.

A plurality of seismic foundation frames are utilized to secure rebar in a fixed location to produce a cementitious supporting form that is embedded in the poured concrete and reinforces the concrete. The frame has an open construction with a plurality of openings to allow the concrete to flow therethrough and to provide increased surface area for reinforcement. The frame has pin openings and rebar openings for receiving and retaining pins or rebar respectively, such as when the frames are stacked. A frame has rebar retainers for retaining rebar that extends perpendicularly to the surface of the frame to a second frame at an offset distance. A flexible containment sleeve is configured around the frames and may be fastened to the frame to create a sleeved form for receiving a cementitious mix. The containment sleeve has apertures for controlled permeation to control the rate of cure of the cementitious mix.

The present invention relates to a free-sliding seabed mudmat foundation, which belongs to the fields of offshore and ocean engineering. The mudmat comprises a base foundation, an upper foundation, and a cover plate. The base foundation sits on the seabed to support dead weights of the mudmat itself and the subsea production system fixed on the mudmat. The upper foundation, with a plurality of universal rolling ball bearing being attached to the bottom, can slide on the base foundation when it is subjected to a horizontal push force generated by the pipeline during operation. Therefore, the axial load on the pipeline during operation due to heating and pressurization is released and the buckling failure risk is then reduced. The mudmat disclosed has smaller size and lighter weight, which is beneficial in reducing fabrication costs and reducing requirements for cranes on the pipeline laying vessel.

The present invention relates to a free-sliding seabed mudmat foundation, which belongs to the fields of offshore and ocean engineering. The mudmat comprises a base foundation, an upper foundation, and a cover plate. The base foundation sits on the seabed to support dead weights of the mudmat itself and the subsea production system fixed on the mudmat. The upper foundation, with a plurality of universal rolling ball bearing being attached to the bottom, can slide on the base foundation when it is subjected to a horizontal push force generated by the pipeline during operation. Therefore, the axial load on the pipeline during operation due to heating and pressurization is released and the buckling failure risk is then reduced. The mudmat disclosed has smaller size and lighter weight, which is beneficial in reducing fabrication costs and reducing requirements for cranes on the pipeline laying vessel.

A civil engineering anti-seismic structure includes a base. A fixing structure is fixedly welded at the bottom center of the base. A through-hole is provided at the top center of the base. Sliding grooves are provided on corresponding inner walls at two sides of the base. Sliding blocks are slidably connected to the sliding grooves inside the grooves and are symmetrically installed at two sides of a sliding plate. A top block is fixedly welded at the top center of the sliding plate (8), and a fixing groove is provided at the top center of the top block. A shock-absorbing damping pad is fixedly adhered to a bottom inner wall of the base. A first limiting plate is fixedly welded around the top portion of the sliding plate, and a second limiting plate is fixedly welded around the through-hole at a top inner wall of the base.

A civil engineering anti-seismic structure includes a base. A fixing structure is fixedly welded at the bottom center of the base. A through-hole is provided at the top center of the base. Sliding grooves are provided on corresponding inner walls at two sides of the base. Sliding blocks are slidably connected to the sliding grooves inside the grooves and are symmetrically installed at two sides of a sliding plate. A top block is fixedly welded at the top center of the sliding plate (8), and a fixing groove is provided at the top center of the top block. A shock-absorbing damping pad is fixedly adhered to a bottom inner wall of the base. A first limiting plate is fixedly welded around the top portion of the sliding plate, and a second limiting plate is fixedly welded around the through-hole at a top inner wall of the base.

A plurality of seismic foundation frames are utilized to secure rebar in a fixed location to produce a cementitious supporting form that is embedded in the poured concrete and reinforces the concrete. The frame has an open construction with a plurality of openings to allow the concrete to flow therethrough and to provide increased surface area for reinforcement. The frame has pin openings and rebar openings for receiving and retaining pins or rebar respectively, such as when the frames are stacked. A frame has rebar retainers for retaining rebar that extends perpendicularly to the surface of the frame to a second frame at an offset distance. A flexible containment sleeve is configured around the frames and may be fastened to the frame to create a sleeved form for receiving a cementitious mix. The containment sleeve has apertures for controlled permeation to control the rate of cure of the cementitious mix.

A plurality of seismic foundation frames are utilized to secure rebar in a fixed location to produce a cementitious supporting form that is embedded in the poured concrete and reinforces the concrete. The frame has an open construction with a plurality of openings to allow the concrete to flow therethrough and to provide increased surface area for reinforcement. The frame has pin openings and rebar openings for receiving and retaining pins or rebar respectively, such as when the frames are stacked. A frame has rebar retainers for retaining rebar that extends perpendicularly to the surface of the frame to a second frame at an offset distance. A flexible containment sleeve is configured around the frames and may be fastened to the frame to create a sleeved form for receiving a cementitious mix. The containment sleeve has apertures for controlled permeation to control the rate of cure of the cementitious mix.

The present invention provides a method and apparatus for energy absorption and vibrational dampening in a horizontal plane. According to a first preferred embodiment, the present invention discloses an apparatus for damping vibration of a pole which includes a housing with a horizontal floor having an inward curved surface for achieving vibration attenuation at a middle portion thereof to form an enclosed chamber. According to a further aspect of the first embodiment, at least one damping weight is preferably disposed in the inward curved surface and is preferably substantially spherical in shape. According to a further preferred embodiment, at least one dampening weight of the present may preferably include a hollow, inner cavity. According to further aspects of the present invention, the dampening weight preferably may further include a granular material located within the inner cavity.