Method and structures for use in mounting a super structure on a foundation pile

Abstract

Method for mounting a super structure over a top end of a foundation pile, wherein the top end has a truncated conical shape and the super structure has an opening fitting over said top end, which opening preferably has a truncated conical peripheral surface fitting over said top end, wherein a guide structure is placed at said top end, comprising at least one sloping guide surface, where after said super structure is lowered over the guide structure onto the top end of the foundation pile.

1 . Method for mounting a super structure over a top end of a foundation pile, wherein the top end has a truncated conical shape and the super structure has an opening fitting over said top end, which opening preferably has a truncated conical peripheral surface fitting over said top end, wherein a guide structure is placed at said top end, comprising at least one sloping guide surface, where after said super structure is lowered over the guide structure onto the top end of the foundation pile. 
     
     
         2 . Method according to  claim 1 , wherein after positioning of the super structure onto said top end of the foundation pile the guide structure is removed from the top end of the foundation pile. 
     
     
         3 . Method according to  claim 1 or 2 , wherein a guide structure is used having a conical or truncated conical guide surface. 
     
     
         4 . Method according to  any one of the previous claims , wherein the guide structure comprises an upper part comprising or forming the guide surface and a lower part, wherein said lower part is inserted into an open end of the top end. 
     
     
         5 . Method according to  claim 4 , wherein said lower part has a substantially conical or truncated shape, wherein at an interface between the upper and the lower part at least one support element is provided, extending outward, wherein the guide structure is lowered into the open end of the foundation pile, such that said at least one support element comes to rest on the foundation pile. 
     
     
         6 . Method according to  any one of the previous claims , wherein the guide structure and the super structure are suspended from a support frame, wherein the guide structure is suspended such that it extends at least partly below the super structure. 
     
     
         7 . Method according to  claim 6 , wherein the guide structure is suspended from said frame by at least one suspension element extending through the opening in the super structure. 
     
     
         8 . Method according to  claim 6 or 7 , wherein the guide structure and the super structure, suspended from the support frame, are lifted to a position above the upper end of the foundation pile, such that the guide structure, especially a lower part thereof, is suspended directly above the top end of the foundation pile, especially an open top end of said foundation pile, where after the support frame is lowered such that the guide structure is at least partly inserted into said open top end of the foundation pile, where after the support frame is lowered further, such that the super structure is lowered over an outer surface of the top end of the foundation pile, forming a slip joint with the foundation pile, where after the super structure is released from the support frame and the support frame is lifted again, pulling the guide structure away from the foundation pile. 
     
     
         9 . Method according to  any one of the previous claims , wherein the super structure is a platform with an upper side and a lower side, and wherein the said opening extends through the platform, from the upper side to the lower side. 
     
     
         10 . Method according to  any one of the previous claims , wherein as a guide structure an open structure is used. 
     
     
         11 . Method according to  any one of the previous claims , wherein by lowering the super structure onto the top end of the foundation pile a slip joint is formed between the super structure and the top end of the foundation pile. 
     
     
         12 . Guide structure for use in mounting a super structure onto a foundation pile according to any one of  claims 1-11 . 
     
     
         13 . Guide structure according to  claim 12 , wherein said guide structure comprises an upper part and a lower part, wherein the upper part comprises or forms a guide surface and the lower part is designed for engaging a top end of a foundation pile, such that during use the lower part enables centering of the guide structure relative to the top end of the foundation pile and the guide surface extends above the top end of the foundation pile for guiding a super structure during lowering of the super structure onto the top end of the foundation pile. 
     
     
         14 . Guide structure according to  claim 13 , wherein the upper part has a configuration with an increasing cross section towards the lower part, and is preferably substantially conical or truncated conical. 
     
     
         15 . Guide structure according to  claim 13 or 14 , wherein said lower part has a configuration with a decreasing cross section in a direction away from the upper part, and preferably has a substantially conical or truncated conical shape. 
     
     
         16 . Guide structure according to any one of  claims 13-15 , wherein the upper part interfaces with the lower part at an interface plane, wherein at the interface plane the upper part extends radially outward from the lower part, such that a support portion is provided by an end of the upper part at the interface plane. 
     
     
         17 . Guide structure according to any one of  claims 12-16 , wherein the structure has a substantially open configuration. 
     
     
         18 . Assembly of a guide structure according to any one of  claims 12-16  and a super structure, wherein the assembly further comprises a support frame, wherein the super structure and the guide structure are supported by the support frame, preferably suspended from the support frame. 
     
     
         19 . Assembly according to  claim 18 , wherein the super structure comprises an opening extending through the super structure, wherein at least one suspension element extends from the support frame through said opening and wherein the guide structure is suspended from said at least one suspension element, such that the guide structure extends at least partly below the said opening. 
     
     
         20 . Assembly according to  claim 19 , wherein said super structure is a platform with the opening extending from an upper side to a lower side of said platform. 
     
     
         21 . Assembly according to any one of  claims 18-20 , wherein the guide structure has a maximum cross section perpendicular to a vertical axis of said guide structure, which maximum cross section is smaller than a minimum cross section of the opening measured perpendicular to a vertical axis of the opening, such that the guide structure can be moved vertically through said opening, wherein said maximum cross section of the guide structure is preferably substantially the same as a minimum outer cross section of the top end of the foundation pile, more preferably such that the guide structure does not radially extend beyond the outer surface of the top end of the foundation pile. 
     
     
         22 . Foundation pile for supporting at least one super structure, especially a monopile for mounting at least a platform by a slip joint, wherein the foundation pile is provided at a top end with a removable guide structure for guiding said super structure relative to the top end during mounting of said super structure.