Marine pier having deeply submerged storage container

• US 4,014,177 A
• Filed: 09/26/1975
• Issued: 03/29/1977
• Est. Priority Date: 09/06/1974
• Status: Expired due to Term

• Current Assignee: National Research Council Canada
• Original Assignee: Canadian Patents and Development Limited
• Inventors: Jarlan, Gerard Eugene
• Primary Examiner(s): Shapiro, Jacob
• Application Number:
  US05/617,091
• Time in Patent Office: 550 Days
• Field of Search: 61/46.5, 61/46, 61/3, 61/4, 61/5, 61/52, 61/87, 61/101, 61/102
• US Class Current: 405/205
• CPC Class Codes: E02B 17/025 Reinforced concrete structures E02B17/021 takes precedence

Abstract

A vertically-elongate monolithic pier body comprises:

A deeply-submerged compartmented closed container or container group;

A near-surface control chamber system;

A deckwork carried above highest wave level;

A load-carrying column and wall system extending in part through the container and chamber system, including a pair of perforated flanking walls; and

A transverse wall and beam bracing framework extending in part through the container and chamber system, including a top wall and a thick slab base.

The pier is intended to stand on seabed in depths of 450 feet to 1200 feet or deeper, to carry petroleum well-drilling and production equipment. The large container group is submerged at a depth where it is subjected to reduced wave pressures. The flanking pair of walls dissipate the energy of incident waves.

Fabrication begins in a drydock site with the pier laid out horizontally extended. The container and chamber end walls are cast flat, and all transverse and load-carrying walls and container sidewalls are upwardly slipformed. The initial structure is self-floated and towed to sheltered water where construction is completed to a height 200 feet or more. The pier is then towed to its site, turned upright, and sunk to stand on seabed. One or more tubular columns not intersecting the container or chamber systems provide drilling passages.

Claims

1. A marine pier structure for sited in the sea on a seabed in depth at least 400 feet, comprising a base slab of rectangular plan form, spaced parallel upright load-carrying walls rising from the base, a container body having parallel plane end walls and a convexly-lobed side wall integrally joined with said end walls and together enclosing a space, said upright walls extending through said container body and supporting said container body in spaced relation above said base and terminating in the sidewall at its upper surface, a system of tubular vertical columns arrayed in parallel files along said terminations of said upright walls and extending to a height near the sea surface, a pair of upright flanking load-carrying walls spaced symmetrically to either side of and parallel with said upright walls a distance about 60 feet from the container side wall, a top wall joining the upper extremities of said flanking walls and a series of tiers of tubular brace members orthogonally disposed to said flanking walls and to said vertical columns and monolithically joined therewith, said flanking walls being extensively perforated by a large multiplicity of regularly distributed transverse jet-guiding channels opening through the walls, having a combined cross-sectional channel area at least about 30% of the elevational area of the walls, a deckwork supported on said upright walls and vertical columns above the sea, and an enclosed chamber integral with said vertical columns having an internal space intersected by said tubular vertical columns.

2. A marine pier structure as set forth in claim 1 wherein said container body side wall has curvatures about line axes parallel with the width dimension of the pier and said upright walls and said side wall and said upright intersecting walls are intersected by two vertically spaced horizontal brace walls subdividing the height of the container body said brace walls extending to and being monolithically joined with said flanking walls.

3. A marine pier structure as set forth in claim 2 wherein said enclosed chamber is subdivided into two halves by a solid wall extending in line with a centered upright intersecting wall and joined with said tubular vertical columns which are aligned with said centered wall.

4. A marine pier structure as set forth in claim 3 wherein said enclosed chamber is intersected by upward continuations of files of tubular vertical columns spaced adjacently to either side of said centered file of columns.

5. A marine pier as set forth in claim 4 wherein a series of slender tubular pillars rise from said top wall which is submerged beneath mean sea surface and extend above highest wave level and are arranged as ranks and files over the upper surface area of at least part of said top wall, at least one central file of said slender tubular pillars having its internal spaces in communication with predetermined ones of other files of said slender tubular pillars having their internal spaces in communication with the upward continuations of tubular vertical columns intersecting said enclosed chamber.

6. A marine pier structure as set forth in claim 3 wherein said enclosed chamber has a convexly lobed side wall and vertical planar end walls integrally joined with said lobed side wall, and said flanking walls have inwardly curved upper terminal portions merging with said top wall and spaced horizontally from the chamber side wall.

7. A marine pier structure as set forth in claim 1 wherein said tubular vertical columns have horizontal cross-sections of which a longer dimension is aligned parallel with the flanking walls.

8. A marine pier structure as set forth in claim 5 wherein said slender tubular pillars rising out of the sea have cylindrical or slightly reducing cross-section upwardly.

9. A marine pier as set forth in claim 8 wherein the structure is disposed as a floating body with its height dimension in the horizontal and the end walls of said container body and of said enclosed chamber horizontal.

10. A marine pier structure as set forth in claim 2 wherein a pair of cylindrical hollow columns have their lower ends integral with the said base slab on opposite sides of said container body, each column extending contiguously adjacent the convexly-lobed side wall of said container body and intersecting said top wall and said deck work, said columns providing unobstructed passages substantially coextensive with the height of said pier.

11. A marine pier structure as set forth in claim 2 wherein a pair of cylindrical hollow columns have their lower ends integral with the said base slab on opposite sides of said container body, each column extending contiguously adjacent the convexly-lobed side wall of said container body and intersecting said deckwork, each said flanking wall comprising a vertical lower portion and an upper portion which is inclined to the vertical and which at its upper extremity merges with said top wall, said columns intersecting respective inclined portions of said flanking walls.

12. A marine pier as set forth in claim 1 wherein said transverse jet-guiding channels have cross-sectional areas which are constant along their length.

13. A marine pier as set forth in claim 1 wherein said transverse jet-guiding channels have cross-sectional areas which decrease along the length of the channel in the direction from the open sea toward the interior of the pier.

14. A marine pier as set forth in claim 1 wherein the transverse jet-guiding channels have smooth surfaces formed by casting said channels as thick-walled tubes of concrete in polished metal molds.

15. A marine pier as set forth in claim 1 wherein the transverse jet-guiding channels have smooth surfaces comprised as cylindrical or conical interior surfaces terminating in end openings formed as convexly-rounded surfaces merged smoothly with the exterior surfaces of the flanking wall.

16. A marine pier as set forth in claim 1 wherein the upright marginal portions of said flanking walls are convexly-rounded in any horizontal plane.

17. A marine pier as set forth in claim 1 having a system of horizontal tubular brace members orthogonally disposed with respect to said tubular vertical columns and extending parallel with the horizontal extents of said flanking walls between the tubular vertical columns of each file and being integrally joined with said tubular vertical columns adjacent their junctions with said tubular beam members.

18. A marine pier as set forth in claim 1 wherein said tiers of tubular beam members intersect ranks of tubular vertical columns in respective horizontal planes spaced apart vertically about 90 feet, an uppermost horizontal tier intersecting said enclosed chamber nearly tangentially of a lower side wall portion thereof and a lowermost horizontal tier intersecting said container body nearly tangentially of an upper side wall portion of said container body.

19. A marine pier as set forth in claim 18 wherein tubular beam members intersect those ranks of tubular vertical columns which extend above the end walls of the container body and also intersect at least one interior rank of tubular vertical columns.

20. A marine pier as set forth in claim 19 wherein there are an odd number of tubular vertical columns in the files of columns rising from the upper termination of each upright load-carrying wall and one pair of horizontal tubular beam members connect said flanking walls with respective outer ranks of said tubular vertical columns and further tubular beam members connect said flanking walls with each odd-numbered interior rank of tubular vertical columns as counted from an outer rank.

21. A marine pier as set forth in claim 3 wherein said solid wall includes passages communicating with the interior spaces of predetermined ones of said tubular vertical columns and communicating with the interior spaces of predetermined ones of said slender tubular pillars.

22. A marine pier as set forth in claim 1 wherein said slab base is a thick monolithic body and has lateral extensions formed as integral flanges projecting outwardly beyond the planes of said flanking walls and beyond the planes of the end walls of said container body.

23. A marine pier as set forth in claim 22 wherein said extensions have sloping upper surfaces and the thickness dimension of said extensions decreases outwardly of the plan outline of the pier.

24. A marine pier as set forth in claim 23 wherein the under surface of said slab base is formed with a pattern of downwardly projecting intersecting ribs.

25. A marine pier as set forth in claim 2 wherein said parallel upright load-carrying walls comprise a centered wall and a pair of auxiliary walls spaced about 90 feet to each side of said centered upright load-carrying wall, and said lobes of said container body sidewall have their marginal portions integrally joined with said auxiliary walls at their junctions with said horizontal bracewalls.

26. A marine pier as set forth in claim 25 wherein said centered upright load-carrying wall and said auxiliary upright load-carrying walls are formed with internal passages communicating with predetermined internal spaces bounded by the plane end walls of said container body and by predetermined ones of said sidewall lobes, said horizontal brace walls, and said upright walls, and said passages communicate with predetermined interior spaces of said vertical tubular columns.

27. A marine pier as set forth in claim 1 wherein said enclosed control chamber has its upper sidewall located about 60 feet below mean sea level and said deckwork is carried at a height about 60 feet above mean sea level by a series of slender tubular pillars.

28. A method of making a marine pier structure as claimed in claim 1 wherein said base, walls, columns, chambers, and container body are at least partially cast together as a unitary structure in a drydock so that the base is substantially vertical and has said columns extending horizontally therefrom, and after said at least partial structure has been cast, the structure is trimmed into a horizontal floating attitude by ballasting displacement volumes and floated to a sheltered sea site and the structure is completed as a monolithic, post-stressed body, the completed pier is then towed base aft to a site area, the structure is caused to be righted with the base down by ballasting at least said container body and said chamber, and the structure is subsequently ballasted further so as to have negative buoyancy so that it stands on seabed.

36. A marine pier as set forth in claim 1 wherein the distance between the sidewall of the enclosed chamber and the nearest flanking wall is at least about 40 feet.

37. A marine pier as set forth in claim 1 wherein the container body is spaced above the slab base about 40 to 60 feet.

38. A marine pier as set forth in claim 1 wherein the upper part of the container body in the standing pier is located at a depth of about 300 feet.

29. The method of fabricating a pier structure of greatly extended height which comprises casting an end wall of a container body as a flat slab in a drydock, casting an end wall of a chamber spaced from said container body as a flat slab in the same plane as said container end wall, casting an upright transverse top wall integral with a margin of said chamber end wall, forming three spaced walls as dividing walls intersecting said container body and extending along the pier length, casting a base slab as a transverse upright wall perpendicular to said dividing walls, casting brace walls parallel with said base slab and intersecting the open container body, erecting upwardly a transversely perforated flanking wall extending horizontally on either side of the container body and extending along either side of said chamber and terminating in said transverse top wall, erecting a system of orthogonally-intersecting tubular columns between said container body and said chamber and said flanking walls, casting tubular pillars as extensions of horizontal tubular columns beyond said chamber, and casting cylindrical hollow columns extending along the sidewall of the container body from the base through said top wall and beyond said chamber, casting at least partial sidewalls on the margins of said container and chamber end walls, floating the structure as a vessel to a sheltered sea site, completing the fabrication of the pier as a unitary monolithic, reinforced and post-stressed floating body, towing completed pier in its horizontal floating and partly-ballasted condition to a deep water site, ballasting said container body and said chamber to turn the pier upright as a vertically-elongate floating structure, and further ballasting the pier to sink it to stand on seabed.

30. The method of fabricating a pier structure as set forth in claim 29 which includes the step of capping the end openings of jet-guiding channel courses adjacent the drydock floor by means of cover members to prevent ingress of water prior to flooding of the drydock to augment buoyancy of the flanking walls.

31. The method of fabricating a pier structure as set forth in claim 29 wherein said slab base is constructed as a compartmented open-topped vessel having a closing bottom wall comprised as a slab extension, end walls comprising further slab extensions, and side walls formed as sheets forming the upper and lower surfaces of the slab base, and said compartments are filled with concrete prior to the righting of the pier into upright attitude.

32. The method of claim 29 wherein the outer ends of said slender tubular pillars are interconnected by a vestigial deckwork of grid form comprised of concrete girders.

33. The method of claim 32 further comprising the step of fabricating a deckwork or deckworks upon the vestigial deckwork after the pier is righted into upright attitude to elevate said vestigial deckwork above the sea.

34. The method of claim 32 wherein said vestigial deckwork is fabricated to integrally join said array of slender tubular pillars with the upper ends of said pair of cylindrical hollow columns.

35. The method of claim 29 wherein the pier is ballasted when in its horizontal floating attitude by admission of seawater to selected compartments of said container body and of said chamber and to some or all of the interior spaces of said tubular columns, and to some or all of said tubular pillar extensions, through predetermined ones of said tubular pillar extensions.

39. The method of righting a marine structure which is in horizontally-elongate stable floating attitude into an upright stable floating attitude, said structure comprising a massive base slab, two laterally-spaced transversely-perforated horizontally-elongate flanking walls extending to one side of the base slab, a closed compartmented container body of large positive buoyancy spaced between said flanking walls and spaced from the base slab and joined by intersecting transverse upright walls and by elongate upright walls with said flanking walls and with said base slab, a plurality of tubular horizontally elongate columns cross-connected by tubular braces extending from a sidewall portion of said container body parallel with said flanking walls, a control chamber having an enclosing upright sidewall and horizontal end-closing walls surrounding outer ends of said pillars remote from said container body, a transverse top end wall integral with said control chamber sidewall connecting terminal portions of said flanking walls, a grid array of slender tubular pillars projecting horizontally parallel with said flanking walls beyond said control chamber sidewall having root ends integral with said top wall and having their outward ends interconnected by beams, the method comprising:

ballasting said container body and said control chamber and tubular columns by admitting predetermined volumes of seawater through at least one above-surface slender pillar into selected tubular columns and interior spaces within said control chamber and within said container body to effect submergence of said base slab, of said container body, of said control chamber, and of said tubular pillars except for at least one rank thereof, the pier floating stably;

admitting further ballasting to compartments of said container body near to said base slab to develop incipient horizontal instability of the structure with said container body wholly submerged and a predetermined initial inclination with base slab downward,

adding further ballast to selected compartments of said container body to induce irreversible loss of horizontal stability and to initiate a progressive righting rotation about a horizontal transverse axis intersecting the control chamber,

then effecting rapid transfer of water ballast from said control chamber interior spaces into lower compartment spaces of said container body through predetermined tubular columns as hydraulic conduits by gravity flow therealong to accelerate righting rotation, while maintaining internal pressure in all pier spaces substantially near the value of sea pressure acting on exterior surfaces and while maintaining said axis sufficiently close to said top wall to maintain the outer ends of a major portion of said slender tubular pillars immersed until the inclination with respect to the horizontal of the tubular pillars of said grid array has reached a predetermined magnitude.

40. The method of claim 39 which includes the step of retaining air or gas as filling of head spaces in the container body and subjecting said air or gas filling to hydraulic fluid pressure developed by the transfer of water ballast along said conduit.

41. A marine pier of vertically-elongate monolithic structural form comprising:

a near-surface control chamber system;

a deeply-submerged storage chamber system including a compartmented closed container or group of containers;

a conduit system communicating with spaces enclosed by said chamber systems;

a load-carrying column and wall system extending in part through said storage and control chamber systems and carrying said conduit system, and a pair of perforated flanking walls spaced on opposite sides of said control chamber system and of said storage chamber system;

a deckwork carried on said load-carrying column and wall system above highest wave level;

a transverse wall and beam bracing framework extending in part through said storage and control chamber systems and uniting said load-carrying column and wall system therewith, and including a top wall and including a slab base spaced below said storage chamber system; and

means for controlling the relative position of the center of mass with respect to the center of buoyancy by transfer of ballast, and for pressurizing the spaces enclosed by said chamber systems by selective admission of gas and/or liquid media, by way of said conduit system.

42. A marine pier as set forth in claim 41, wherein said conduit system is incorporated in or comprises tubular passages in at least the portion of said column and wall system which extends between said deckwork and the spaces enclosed by said control chamber system and said storage chamber system.

43. A marine pier as set forth in claim 41 wherein said top wall is beneath the sea surface and said deckwork is carried by a group of slender tubular pillars having their root ends fixed in the top wall and their upper ends tied by a gridwork of beams above the sea, and one or more of said tubular pillars form part of said conduit system.

44. A marine pier as set forth in claim 41 wherein said top wall is disposed above highest wave level and is supported by the load-carrying column and wall system which extends through the control chamber system, said load-carrying column and wall system carrying upper extremities of said conduit system.

45. A marine pier as set forth in claim 44 wherein said closed container or container group extends continuously to near sea surface as a unitary body, and said control chamber comprises upper compartments of said body.

46. A marine pier as set forth in claim 41 wherein a pair of said load-carrying columns comprise tubes extending between the slab base and the deckwork without intersecting said container or container group or said control chamber.

47. A marine pier of vertically-elongate monolithic structural form comprising:

a deeply-submerged storage chamber system including a compartmented closed container or group;

a near-surface control chamber system;

a deckwork carried above highest wave level;

a load-carrying column and wall system extending in part through the storage and control chamber systems including a pair of perforated flanking walls; and

a transverse wall and beam bracing framework extending in part through said storage and control chamber systems including a top wall, and including a slab base spaced below the container or group;

wherein said storage chamber system extends continuously to near sea surface as a unitary body integral with said control chamber system and wherein the latter comprises upper compartments of said body, the chamber spaces being in fluid communication with tubular passages carried to the deckwork by said column and wall system.

48. A marine pier structure for sited in the sea on a seabed in a depth at least 400 feet, comprising:

a base slab of rectangular plan form,

a system of parallel upright load-carrying walls rising from the slab base at least to maximum wave height,

a storage container body of compartmented monolithic form carried on said system of walls and having its upper part located in a depth about 300 feet below mean sea surface and its lower part spaced above said base slab to provide a flow passage for relief of pressure generated by deep sea wave phenomena,

a deckwork supported above maximum wave height upon said load-carrying walls,

said system of load-carrying walls including a pair of perforated flanking walls spaced symmetrically to either side of said container body a distance about 60 feet and rising to near sea surface or above mean sea level, and

a system of tubular passages carried by said load-carrying walls, at least some of said passages extending to said deckwork and communicating with spaces of said container body.

49. An easily installed stable storage apparatus for storing fluid beneath the surface of a body of water, comprising:

A. a base;

B. a deckwork;

C. a control chamber system containing at least one control chamber space;

D. a fluid storage chamber system containing at least one fluid storage space;

E. support means for forming a unified structure including said deckwork, said control and fluid storage chambers and said base and for positioning said deckwork above the body of water, said control chamber near the surface of the body of water and the fluid storage chamber deeply within the body of water, said support means including;

a. load carrying members oriented vertically when in operative position extending in part through said control chamber space and through said fluid storage space,

b. transverse bracing members extending in part transverse through said control chamber space and said fluid storage space when in operative position, said transverse bracing members intersecting and uniting said load carrying members therewith;

c. stabilizing means for dissipating the effects of wave motion within the body of water said stabilizing means including a pair of perforated flanking walls; and

F. control means for controlling the relative position of the center of mass with respect to the center of buoyancy of said unified structure by selective transfer of material into and out of said control chamber and said fluid storage chamber, said control means including a conduit system for communicating with said control chamber space and said fluid storage space.

50. Apparatus as defined in claim 49, wherein said fluid storage chamber has a lower extremity spaced above said base to form a flow passage for relief of pressure generated by deep water wave phenomena.