Grout Injection Equipment

Abstract

The present invention provides an apparatus for injecting grout into an area between a tubular submarine foundation pile and a leg of an offshore structure inserted into the foundation pile, the apparatus comprising a rigid tube adapted to be inserted into the area, the rigid tube having an inlet for receiving grout and an outlet.

Description

[Technical field]

[0001] The present invention relates generally to grout injection apparatus and more particularly, but not exclusively, to an apparatus for injecting grout into the feet of an offshore structure and a method for fastening an offshore structure to pre-driven foundation piles. [Background technology]

[0002] Marine structures common to both the offshore wind and offshore oil and gas industries most often include a structural jacket that supports a payload above the water line In the offshore wind industry, the payload is a wind turbine, and in the offshore oil and gas industry, the payload tends to be a processing and / or habitation platform.

[0003] The structural jacket is secured to the seabed via one or more foundation piles, which often take the form of hollow tubes driven into the seabed. To secure the structural jacket to the foundation piles, and thus to the seabed, a cementitious material, commonly known as grout, is injected into the foundation. The grout is injected to fill the joints between each foundation pile and each leg of the jacket. The grout is then allowed to harden. Conventionally, the grout is injected through pipes or hoses from a pumping device above the water surface. In particular, suitable piping or hoses are most commonly provided within the leg(s) of the jacket structure and the penetrations of the leg(s) to deliver the grout to the desired area(s). Summary of the Invention

[0004] According to one aspect of the invention, there is provided an apparatus for injecting grout into an area, such as an annular area, between a tubular subsea foundation pile and a foot of an offshore structure inserted into the foundation pile, the apparatus comprising a rigid tube adapted or configured to be inserted into the area, the rigid tube having an inlet for receiving grout and an outlet.

[0005] The feet of the offshore structure may not have internal and / or integral means for transporting grout to the tubular seabed foundation piles.

[0006] The outlet may be located in a sidewall of the rigid tube.

[0007] The rigid tube can, for example, have a closed end opposite an inlet end.

[0008] The outlet may be located in a sidewall of the rigid tube adjacent the closed end.

[0009] The legs of the offshore structure may be or may include jacket legs. The legs or jacket of the offshore structure may be inserted into the open ends of the foundation piles. The foundation piles may be pre-driven foundation piles.

[0010] The rigid tube may include a plurality of outlets. The plurality of outlets may be disposed in a sidewall of the rigid tube. The outlets may be circumferentially spaced about the rigid tube. The outlets may be equally circumferentially spaced about the rigid tube.

[0011] The sidewall of the rigid tube may be provided with markings or indicia that, in use, provide or are configured to provide an indication of the depth to which the outlet is inserted into the foundation pile.

[0012] The markings or indicia may provide, or be configured to provide, an indication of the depth to which, in use, the rigid tube, closed end, or outlet is inserted into the foundation pile.

[0013] The markings or indicia may be printed, stamped, and / or embossed into the sidewall of the rigid tube.

[0014] The closed end may be provided by a plug or cap, which may be removable.

[0015] The closed end may be provided by an attached, for example welded, metal disc.

[0016] The rigid tube may be formed from steel, such as stainless steel or galvanized steel. By way of example, the rigid tube may be formed from any suitable metal alloy. The rigid tube may also be formed from a composite material, such as carbon fiber reinforced polymer (CFRP).

[0017] The apparatus may further comprise a flexible conduit or hose. The flexible conduit or hose may have a first end for connection to a source of grout, such as a pump unit. The flexible conduit or hose may have a second end connected to or for connection to a rigid pipe.

[0018] The rigid tube may be removably connected or connectable to a flexible conduit or hose.

[0019] The first end of the rigid tube may be connected or adapted to connect to a flexible conduit or hose.

[0020] It will be appreciated that the apparatus is separate from the offshore structure and foundation piles. For example, the apparatus may be on board and deployed from a vessel, such as a supply vessel.

[0021] By providing the apparatus separately from the offshore structure and foundation pile, the apparatus is reusable and can therefore be used on multiple offshore structures, which is particularly advantageous where there is no integrated means for delivering grout to the foundation pile, e.g., integrated conduits on the offshore structure or foundation pile.

[0022] The rigid tube may have an inner or outer diameter of 2 inches to 4 inches (5.08 cm to 10.16 cm). The flexible conduit may have an inner or outer diameter of 2 inches to 4 inches (5.08 cm to 10.16 cm).

[0023] The apparatus may include a flange. The flange may be configured to be attached to the foot. The flange may be configured to limit the extent to which the foot may be inserted into the foundation pile. Advantageously, the flange may be attached to the foot to define a spacing between an end of the foot and the seabed within the foundation pile.

[0024] The device or flange may be provided with a funnel guide which may, for example, be arranged to guide the rigid tube into the foundation pile, in use.

[0025] The funnel guide may include a conical portion. The conical portion may be configured, in use, to be positioned on or near the open end of the foundation pile. The funnel guide or conical portion may be configured to guide the rigid tube into the foundation pile.

[0026] The flange may be a radially extending flange. The flange may be configured to engage or be positioned on an open end of the foundation pile. The flange may have one or more openings extending therethrough, for example, for positioning the rigid tube relative to the foundation pile in use. The or each opening may have, for example, a conical portion extending from or around each opening to guide the rigid tube towards the respective opening.

[0027] The flange may include three openings spaced circumferentially around its circumference, e.g., equally spaced. The openings may be configured to position the rigid tube in a circumferential position relative to the foundation pile, in use. The flange may include openings spaced at 45 degree, 90 degree, 120 degree, or 180 degree intervals.

[0028] According to another aspect of the present invention, there is provided an offshore structure foundation construction system comprising the above-mentioned apparatus, an offshore structure having legs, and foundation piles.

[0029] Preferably the feet have no integrated means for conveying grout to the foundation pile, in particular there are no integrated conduits in the offshore structure or in the foundation pile.

[0030] According to another aspect of the invention there is provided a kit of parts comprising a rigid tube as described above and a flexible conduit or hose as described above.

[0031] The kit of parts may include a source of grout, such as a pump unit or grout pump. Additionally or alternatively, the source of grout may comprise a hopper or other storage tank for grout.

[0032] According to another aspect of the present invention, there is provided a method for fixing an offshore structure to a subsea foundation pile, the foundation pile comprising a tube driven into the seabed and the offshore structure comprising a leg to be inserted into the foundation pile, the method comprising: lowering a rigid tube into a region formed between the foundation pile and the leg, for example an annular region, such that an outlet of the rigid tube is in a first position; and injecting grout through the rigid tube into the first region between the end of the leg and the seabed within the foundation pile.

[0033] The foundation piles may be pre-driven foundation piles. The feet of the offshore structure may not have internal and / or integrated means for delivering grout to the tubular seabed foundation piles.

[0034] The rigid tube can be inserted into the region, for example the annular region, such that when in the first position the rigid tube rests on the seabed within the foundation pile. The rigid tube may be inserted into the region such that when in the first position the closed end is in contact with or rests on the seabed. The rigid tube may be inserted into the region such that when in the first position the closed end is proximate or adjacent to the seabed.

[0035] After the grout is injected into the first region, the method can include raising the rigid pipe so that the outlet is at a second location above the first location. The method can include supplying grout to the second region, the second region being an annular region formed between the foot and the foundation pile.

[0036] When the outlet is in the second position, the grout can be conveyed until it fills or overflows the foundation pile.

[0037] The grout filling or overflowing of the foundation pile may be determined acoustically and / or visually. The grout filling or overflowing of the foundation pile may be determined using a remotely operated vehicle (ROV). The grout filling or overflowing of the foundation pile may be determined using a density meter or density gauge, such as an ultrasonic density meter or density gauge, or a nuclear density meter or density gauge.

[0038] The offshore structure may be configured to support a payload above the water surface. After grouting is completed, the payload may be attached to the offshore structure, such as its jacket. The payload may be or may comprise a wind turbine or an oil and gas platform.

[0039] The method may be particularly advantageous where the payload is a wind turbine. In such a case, the offshore structure may be subject to cyclical lateral loads, for example due to wind and / or wind turbine operation. The structural integrity of the foundation as a result of the present invention may provide a more reliable structure when subjected to such lateral loads.

[0040] It is expressly intended that within the scope of this application, the various aspects, embodiments, examples, and alternatives described in the preceding paragraphs, claims, and / or the following description and drawings, in particular their individual features, may be employed independently or in any combination. That is, all embodiments, and / or features of any embodiment may be combined in any manner and / or combination, except where such features are incompatible. For the avoidance of doubt, the terms "may," "and / or," "for example," and any similar terms used herein should be interpreted in an open-ended manner such that any feature so described may not be present. Indeed, any combination of optional features, whether or not they are expressly claimed, is expressly contemplated without departing from the scope of the invention. The applicant reserves the right to modify the claims as originally filed, or to file new claims accordingly, including the right to amend the claims as originally filed to rely on and / or incorporate features of other claims, even if not originally claimed as such.

[0041] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which: [Brief description of the drawings]

[0042] [Figure 1] FIG. 1 is a diagram showing an offshore structure fixed to foundation piles. [Diagram 2] FIG. 2 shows a joint between the foot of an offshore structure and a foundation pile. [Diagram 3] FIG. 2 is a side view showing the insertion portion of the leg of the marine structure. [Figure 4] 1 is a schematic cross-sectional view showing the state in which the legs of the marine structure are inserted into the foundation piles. [Diagram 5] FIG. 5 shows the arrangement of FIG. 4 including a device for injecting grout. [Figure 6a] FIG. 6 is a schematic diagram of the device of FIG. 5 in a first position. [Figure 6b]FIG. 6 is a schematic diagram of the device of FIG. 5 in a second position. [Figure 7] FIG. 6B shows a rigid tube of the device of FIGS. 5, 6a and 6b. [Figure 8] FIG. 8 shows a funnel-shaped guide for guiding the device of FIGS. 5 to 7 during use. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0043] Certain terminology is used in the following description for convenience only and is not limiting of the invention. The words "right", "left", "down", "up", "front", "rear", "upward", "down" and "downward" designate directions in the referenced drawings and relate to the described components when assembled and mounted. The words "inner", "inwardly" and "outer", "outwardly" refer to directions toward and away from a designated centerline or the geometric center (e.g., central axis) of the described element, respectively, with the specific meaning being readily apparent from the context of the description. In particular, the words "upstream" and "downstream" designate directions that refer to the direction of fluid flow within a pipe.

[0044] Furthermore, as used herein, the terms "connected," "attached," "coupled," and "mounted" are intended to include a direct connection between two members with no other intervening members, and an indirect connection between members with one or more intervening members. The terminology includes the terms specifically mentioned above, derivatives thereof, and similar terms.

[0045] Further, unless otherwise specified, the use of ordinal adjectives such as "first," "second," "third," etc., is intended merely to indicate that different instances of similar objects are being referred to, and does not imply that the objects so described must be in a particular order, whether in time, space, precedence, or in any other manner.

[0046] Referring now to FIG. 1, an offshore structure 1 for supporting a payload (not shown) above the surface of a body of water is shown. In various examples, the payload (not shown) may be a wind turbine or an oil and gas platform. The offshore structure 1 includes a jacket 2 having three legs 3. In this example, the legs 3 are interconnected by cross members 4. Each leg 3 has a body 3a and a penetrating portion 3b (as shown more clearly in FIG. 3 ). Each of the body 3a and the penetrating portion 3b is a hollow steel tube in this example. In other examples, the body 3a and the penetrating portion 3b of each leg 3 may comprise different materials and constructions. In this example, the offshore structure 1 has three legs 3, but it will be understood that the offshore structure 1 may have any number of legs 3, including four legs 3.

[0047] The marine structure 1 is fixed to the seabed by being fixed to foundation piles 5, which in this example are hollow steel pipes pre-driven into the seabed. The penetrating portion 3b of each leg 3 is received within an open end 50 of the respective foundation pile 5. A cementitious material in the form of a grout is used to at least substantially fill the remaining area or volume between the penetrating portion 3b and the foundation pile 5 (in particular the area or volume consisting of areas A and B as shown in Figures 4 and 5), thereby fixing the jacket 2 to the foundation pile 5.

[0048] 2, the interface between the jacket 2 and the foundation pile 5 is shown with the penetrating portion 3b inserted into the foundation pile 5. Each leg 3 has a flange 30a disposed between the body 3a and the penetrating portion 3b. The flanges 30a extend in a radial direction. When the respective penetrating portion 3b is disposed within the respective foundation pile 5, the flanges 30a rest against a rim at the open end 50 of the foundation pile 5. The position of the flanges 30a on the legs 3 defines the amount of the legs 3, and in particular the penetrating portion 3b, that is inserted into the foundation pile 5. An overflow outlet 35b (shown more clearly in FIG. 4) extends through the flanges 30a to allow excess grout to overflow during the grouting operation, as will be further explained below.

[0049] 3, the penetrating portion 3b of the leg 3 is shown. At the end of the penetrating portion 3b, distal to the flange 30a, is a tapered end portion 30b. The end portion 30b may be integral with the tubular portion of the penetrating portion 3b or may be formed by a cap that is inserted into the end of the penetrating portion 3b. The end portion 30b includes a plurality of circumferentially spaced radially extending fins 31b. The shape of the end portion 30b is configured to facilitate placement of the penetrating portion 3b within the respective foundation pile 5 and thus facilitate insertion of the leg 3 into the foundation pile 5.

[0050] A side wall 32b extends between the flange 30a and the end portion 30b. In this example, the penetrating portion 3b includes a plurality of shear keys 33b located along the length of the side wall 32b between the flange 30a and the end portion 30b. The shear keys 33b are preferably formed by ridges on the surface of the penetrating portion 3b. The shear keys 33b are configured to provide resistance to relative translational movement between the penetrating portion 3b and the foundation pile 5 after the foot 3 is grouted to the foundation pile 5, thereby improving the fixation of the foot 3 to the foundation pile 5.

[0051] Referring now to FIG. 4, when the penetrating portion 3b is placed within the foundation pile 5, as described above, the flange 30a acts as a stopper, limiting the depth to which the penetrating portion 3b extends into the open end of the foundation pile 5.

[0052] In some examples, the underside of the flange 30a has a circumferentially extending seal 34b in the form of an elastomeric O-ring configured to seal against the free end 50 of the foundation pile 5. Radially inward of the circumferentially extending seal 34b is the overflow outlet 35b described above. The flange 30a may also include a further opening in the form of an inlet 31a for receiving the stinger 7, or its rigid tube 71 (as shown in FIG. 5).

[0053] 4 shows the dredge line D, which is the level of the seabed within the foundation pile 5 after the pile driving operation has taken place. In this example, the dredge line D is located below the surrounding seabed (not shown), but may alternatively be at the same level as the seabed or above it. As shown, the leg 3 is inserted within the foundation pile 5 such that the end portion 30b is spaced apart from the seabed within the foundation pile 5 (i.e., spaced apart from the dredge line D).

[0054] With the penetrating portion 3b positioned within the foundation pile 5, an area A is formed between the end portion 30b and a dredge line D within the foundation pile 5. Additionally, an annular area B is formed between the side wall 32b and an inner wall 51 of the foundation pile 5. During a grouting process (described below), grout is supplied to areas A and B. When areas A and B are full, grout overflows from the annular area B through an outlet 35b. The seal 34b is configured to prevent leakage of grout from any point or area other than the outlet 35b.

[0055] In this example, it will be appreciated that in the case of a jacket 2 having multiple legs 3, each leg 3 has the arrangement shown in Figure 4. In this case, the jacket leg(s) 3 and the penetration portion(s) 3b do not have internal piping or hoses for transporting grout material to the area.

[0056] In order to secure the legs 3 to the foundation piles 5, the seabed is preferably dredged prior to installation of the foundation piles 5. One or more foundation piles 5 are then driven into the seabed to a desired depth, with the open ends 50 of each pile 5 projecting above the seabed. The jacket 2 is then lowered toward the seabed, with each penetration portion 3b positioned within the open ends 50 of each foundation pile 5. The jacket 2 is lowered until each flange 30a is supported by its respective open end 50, forming regions A and B. Grout is then injected into regions A and B, as described below.

[0057] 5 to 7, there is shown an apparatus for injecting grout into an offshore structure 1 having a leg 3 inserted into a foundation pile 5. In particular, the apparatus is for filling the above-mentioned areas A and B with grout. In this example, a stinger 7 extends from a vessel V (FIGS. 6a, 6b) above the water surface. The stinger 7 extends through an inlet 31a into a volume formed between the penetration portion 3b and the foundation pile 5.

[0058] As shown most clearly in Figures 6a and 6b, the stinger 7 comprises a flexible conduit or hose 70 having a first end 70a connected to a source of grout, in particular a pump unit P on board the vessel V, and a second end 70b connected to a rigid tube 71. The rigid tube 71 is made of steel in this example. The flexible conduit 70 is hoisted by a crane C on board the vessel V, but may additionally or alternatively be placed on a reel or spool. The flexible conduit 70 supports the weight of the rigid tube 71 and is a conduit for the grout, or alternatively the rigid tube 71 is suspended on a tether with a separate conduit for supplying grout to the rigid tube 71. For example the rigid tube 71 may be suspended on a chain whilst a hose supplies grout to the rigid tube 71.

[0059] Specifically, as shown in Figure 7, the rigid tube 71 has a first open end 710 for connection with the flexible conduit 70 and a second closed end 711 opposite the first end 710. A sidewall 712 of the rigid tube 71 proximate the closed end 711 in this example has a grout outlet 72. The closed end 711 is preferably provided by a welded cap, but may also be folded closed or plugged.

[0060] The exterior surface of the side wall 712 is provided with indicia or markings 73 along the length of the rigid tube 71. In this example, the indicia or markings 73 designate the distance from the center of the outlet 72 to discrete points along the length of the rigid tube 71. Such indicia 73 provide an indication of the depth to which the outlet 72 has been inserted into the volume between the penetration portion 3b and the foundation pile 5.

[0061] Alternatively, the indicia 73 may designate the distance from the closed end 711 to a discrete point along the length of the rigid tube 71 .

[0062] The grouting operation using the device of Figures 5 to 7 is carried out as shown in particular in Figures 5, 6a and 6b. The stinger 7 is connected to a pump unit P and lowered from the vessel V towards the seabed S (Figures 6a and 6b). The rigid pipe 71 is aligned with the inlet 131a and lowered into the volume formed between the penetration portion 3b and the foundation pile 5.

[0063] In a first stage, the stinger 7 is lowered to a first position P1, as shown in dashed outline in FIG. 6 and also in FIG. 6a. In the first position P1, the closed end 711 is located at or near the dredge line D in the foundation pile 5. To reach this position, the stinger 7 can be lowered until the tension in the tether is reduced (indicating that the stinger 7 is resting on the seabed). Optionally, the stinger 7 can then be raised slightly to lift it off the seabed. Next, a pump unit P is used to convey grout along the stinger 7 to the outlet 72. The grout is conveyed until the area A is filled. Preferably, a predetermined volume of grout is conveyed to the area A. The predetermined volume is based on the known inner diameter of the foundation pile and the specified distance between the seabed (i.e. the dredge line) and the penetration portion 3b in the foundation pile 5. In another example, the stinger 7 and / or the penetrating portion 3b may include a sensor that detects when the grout in region A reaches a certain height along the length of the rigid tube 71 that corresponds to a desired depth in region A.

[0064] In this example, once area A is full, the stinger 7 is raised by crane C and the grout filling area A is allowed to harden to a predetermined extent. The extent of hardening can be determined based on the temperature of the water and the known hardening rate of the grout. The grout injected into area A may be allowed to harden until it is set or hardened, or until it is substantially set or hardened. The grout injected into area A may be allowed to harden until it reaches its final set state.

[0065] As shown in solid outline in Figure 5 and also shown in Figure 6b, the stinger 7 can be raised to a second position P2 above the first position and above area A. In some examples, the stinger 7 is removed from the foundation pile 5 and moved to another foundation pile 5 of the offshore structure 1 to repeat the injection of grout into area A, as described further below.

[0066] After the grout filled area A has hardened to a predetermined extent, the stinger 7 is moved to a second position P2.

[0067] Next, with the stinger 7 in the second position P2, the pump unit P is used to convey the grout along the stinger 7 to the outlet 72 to fill the area B. The grout is conveyed until the area B is filled.

[0068] In this example, the filling of area B is identified by the presence of grout at the overflow outlet 35b. However, it will be appreciated that instead of providing an overflow outlet 35b, the filling of area B may be determined using a density gauge or densitometer, or acoustically, for example by an acoustic sensor on the remotely operated vehicle (ROV) or on the foot 3. Alternatively, the filling of area B may be determined by using a pressure sensor or transducer located either on the stinger 7 or in the volume formed by areas A and B. In such a case, if there is no overflow outlet 35b (or the overflow outlet 35b is restricted), a pressure rise may be detected when area B is full if the pump unit P remains activated. In another example, a predetermined volume of grout is delivered to area B based on the known dimensions of the penetration portion 3b and the foundation pile 5. Such an example may be advantageous in order to prevent overflow of grout when the flange 30a is not provided.

[0069] 8, there is shown a funnel-shaped guide 8 for guiding the stinger 7 through the inlet 31a of the flange 30a and into the volume between the penetration portion 3b and the foundation pile 5. The funnel-shaped guide 8 has a conical portion 80 that tapers towards the inlet 31a. In this example, associated with the conical portion 80 is a sleeve 81 that is configured to be inserted into the inlet 31a.

[0070] In the example, the funnel guide 8 may be integrally formed with the flange 30a.

[0071] In use, the funnel guide 8 is used to provide a larger target area for the stinger 7, and in particular its rigid tube 71. This makes it easier to align the stinger 7 with the inlet 31a as it is lowered towards the seabed.

[0072] It will be appreciated by those skilled in the art that several variations to the above described embodiments are envisaged without departing from the scope of the present invention.

[0073] Moreover, it will be appreciated by those skilled in the art that combinations of any number of the features set forth above and / or illustrated in the accompanying drawings provide distinct advantages over the prior art and, therefore, are within the scope of the invention as described herein.

Claims

1. 1. An apparatus for injecting grout into an annular region between a tubular offshore foundation pile and a leg of an offshore structure inserted into said tubular offshore foundation pile, said apparatus comprising a rigid tube adapted to be inserted into said annular region, said rigid tube having an inlet for receiving grout, a side wall, an outlet disposed in said side wall, and a closed end opposite to said inlet end, said closed end being provided by a plug or cap.

2. 2. The apparatus of claim 1, wherein the legs of the offshore structure do not have internal and / or integrated means for transporting grout into the tubular seabed foundation pile.

3. 3. The apparatus of claim 1 or 2, wherein the rigid tube includes a plurality of outlets disposed in the side wall, the outlets being circumferentially spaced about the circumference of the rigid tube.

4. 4. The apparatus of any one of claims 1 to 3, wherein the side wall of the rigid tube includes markings configured to provide an indication of the depth to which, in use, the outlet is inserted into a tubular offshore foundation pile.

5. 5. The apparatus of claim 1, further comprising a flexible conduit having a first end for connection to a source of grout and a second end connected to the rigid pipe.

6. The apparatus of any one of claims 1 to 5, wherein the rigid tube has a diameter of between 2 inches and 4 inches (5.08 cm to 10.16 cm).

7. The apparatus of any one of claims 1 to 6, further comprising a flange attached to the foot and configured to limit the extent to which the foot can be inserted into the tubular seabed foundation pile.

8. The apparatus of claim 7 , wherein the flange comprises a funnel-shaped guide arranged to guide the rigid tube into the tubular seabed foundation pile.

9. 9. Apparatus as claimed in claim 8, wherein the flange further comprises one or more openings extending therethrough for positioning the rigid tube against a tubular offshore foundation pile in use, the or each opening having a conical portion extending therearound for guiding the rigid tube towards the opening.

10. An offshore structure foundation construction system comprising the device according to any one of claims 1 to 9, an offshore structure having legs, and tubular seabed foundation piles.

11. The offshore structure foundation construction system according to claim 10, wherein the legs of the offshore structure do not have integrated means for transporting grout into the tubular seabed foundation piles.

12. 5. A kit of parts comprising the apparatus of any one of claims 1 to 4 and a flexible conduit having a first end for connection to a source of grout and a second end connected to the rigid pipe.

13. 13. A method for fixing an offshore structure to a pre-installed tubular offshore foundation pile, the tubular offshore foundation pile comprising a rigid tube installed in the seabed, the offshore structure comprising a leg to be inserted into the tubular offshore foundation pile, the method comprising: lowering an apparatus as described in claim 1 into an annular region formed between the tubular offshore foundation pile and the leg so that an outlet of the rigid tube is in a first position; and injecting grout through the rigid tube into a first region between an end of the leg and the seabed within the tubular offshore foundation pile.

14. The method of claim 13 , wherein the legs do not include integrated means for transporting grout into the tubular seabed foundation pile.

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