OFFSHORE SUBSTRUCTURE SUPPORTED BY TEMPLATE-INTEGRATED SUCTION FOUNDATION AND INSTALLATION METHOD THEREOF

Abstract

The present disclosure relates to an offshore substructure supported by a template-integrated suction foundation and an installation method thereof, more particularly to an offshore substructure installed by pre-piling construction including: a suction foundation having a plurality of suction piles pre-inserted into the seabed by suction, joint sockets connected to each head part of the suction piles, and connecting members connecting spaces between the joint sockets; and a substructure connected onto an upper part of a suction foundation pre-piled, wherein an insertion socket connected to a lower part of the substructure is inserted into the joint socket, and the suction foundation and the substructure are connected by grouting a space between the insertion socket and the joint socket.

Claims

1. An offshore substructure supported by a template-integrated suction foundation, as an offshore substructure installed by pre-piling construction, comprising: a suction foundation having a plurality of suction piles pre-inserted into the seabed by suction, joint sockets connected to each head part of the suction piles, and connecting members connecting spaces between the joint sockets; and a substructure connected onto an upper part of a suction foundation pre-piled, wherein an insertion socket connected to a lower part of the substructure is inserted into the joint socket, and the suction foundation and the substructure are connected by grouting a space between the insertion socket and the joint socket.

2. The offshore substructure supported by a template-integrated suction foundation of claim 1, wherein a plurality of studs are installed in an inner surface of the joint socket and outer surface of the insertion socket, respectively.

3. The offshore substructure supported by a template-integrated suction foundation of claim 2, wherein the suction foundation is manufactured as one body and conveyed to a construction site, and then is inserted into a set position, a position and a height of the suction pile are controlled through a suction unit, an upper flange provided to an upper part of the joint socket, and a lower flange provided between a substructure body and the insertion socket are included, the upper flange and the lower flange are in contact with each other during installation, and a gripper unit fixing a space between the insertion socket and the joint socket is included so as to prevent relative displacements of the substructure and the suction foundation until grout is hardened.

4. An installation method of an offshore substructure supported by a template-integrated suction foundation, as a method of installing an offshore substructure installed by pre-piling construction, comprising steps of: manufacturing a suction foundation having a plurality of suction piles, joint sockets connected to each head part of the suction piles, and connecting members connecting spaces between the joint sockets; after seating the suction foundation on the seabed where to be constructed, installing the suction foundation by inserting the suction pile into a position where to be constructed of the seabed; inserting an insertion socket to be installed to a lower part of a substructure, inside the joint socket; and connecting the insertion socket and the joint socket by grouting a space therebetween.

5. The installation method of an offshore substructure supported by a template-integrated suction foundation of claim 4, wherein a gripper unit fixes a space between the insertion socket and the joint socket so as to prevent relative displacements of a substructure and the suction foundation until grout is hardened.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings of this specification exemplify a preferred embodiment of the present disclosure, the spirit of the present disclosure will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, and thus it will be understood that the present disclosure is not limited to only contents illustrated in the accompanying drawings;

[0028] FIG. 1 to FIG. 4 are cross-sectional views each showing a pre-installation process of a foundation structure using a template(s) in the prior art pre-piling construction,

[0029] FIG. 5 and FIG. 6 cross-sectional views each showing a connection process of a substructure to the inside of a pre-piled pile,

[0030] FIG. 7 is a cross-sectional view showing a state that a height of a stud in an insertion portion of a prior art insertion pile is not equal to that of a stud in the joint of the jacket leg,

[0031] FIG. 8 is a plane view showing a state that a joint of a prior art jacket leg is not placed in the middle of an insertion portion of the insertion pile,

[0032] FIG. 9 is a cross-sectional view showing a substructure having a prior art suction foundation,

[0033] FIG. 10 to FIG. 12 are cross-sectional views each showing an installation process of an offshore substructure supported by a template-integrated suction foundation according to an embodiment of the present disclosure,

[0034] FIG. 13 is a plane view showing a suction foundation according to an embodiment of the present disclosure,

[0035] FIG. 14 is a flowchart showing an installation method of an offshore substructure supported by a template-integrated suction foundation according to an embodiment of the present disclosure,

[0036] FIG. 15 is a cross-sectional view showing a suction foundation pre-installed (left hand side) and a state that a substructure is connected to the suction foundation (right hand side), according to an embodiment of the present disclosure.

FIGURE REFERENCE NUMBERS

[0037] 1: seabed [0038] 2: crane [0039] 3: template [0040] 4: insertion pile [0041] 5: insertion portion [0042] 6: stud [0043] 7. suction pile-integrated substructure [0044] 10: substructure [0045] 11: jacket leg [0046] 12: body [0047] 13: insertion socket [0048] 14: jacket stud [0049] 15: lower flange [0050] 20: suction foundation [0051] 21: suction pile [0052] 22: joint socket [0053] 23: connecting member [0054] 24: suction foundation stud [0055] 25: upper flange [0056] 30: grout [0057] 100: offshore substructure supported by a template-integrated suction foundation

DETAILED DESCRIPTION

Best Mode

[0058] Hereinafter, described are configuration and functions of an offshore substructure supported by a template-integrated suction foundation according to an embodiment of the present disclosure, and an installation method thereof.

[0059] Firstly, FIG. 10 to FIG. 12 are cross-sectional views each showing an installation process of an offshore substructure supported by a template-integrated suction foundation according to an embodiment of the present disclosure.

[0060] As shown in FIG. 10, according to the present disclosure, it is seen that a suction foundation 20 is applied as a foundation of a pre-pile in advance. That is, the suction foundation is manufactured and conveyed to a construction site. Then, the suction foundation 20 is inserted into the seabed 1.

[0061] FIG. 13 is a plane view showing a suction foundation according to an embodiment of the present disclosure. It is seen that the suction foundation 20 according to the present disclosure has a plurality of suction piles 21 to be inserted to the seabed 1 by suction, joint sockets 22 connected to each head part of these suction piles 21, and a connecting members 23 made of a rigid material and connecting an in-between space of the joint sockets 22.

[0062] That is, a plurality of the suction piles (21) having a cylinder shape is manufactured on the basis of a design taking account of ground characteristics at an installation site. The plurality of the suction piles 21 is connected with the connecting member 23 securing rigidity enough to maintain mutual positions thereof.

[0063] The joint socket 22 where a substructure 10 should be connected is formed in a head part of the individual suction pile 21. A plurality of studs 24 is arranged inside this joint socket 22 according to the design procedure.

[0064] The suction foundation 20 is seated on the seabed 1, and then the suction pile 21 is inserted into the seabed 1 while controlling a suction unit (not illustrated) to adjust a positon of the suction foundation 20. Accordingly, as applying this suction foundation 20 to pre-piling construction, the suction pile 21 is accurately inserted at a set position without using a template 3. Whereby an error in heights of the studs 24 can be minimized and an error in a joint can be likewise minimized.

[0065] Further, a jacket leg 11 of the substructure 10 is connected to an upper part of the suction foundation 20 pre-piled. That is, an insertion socket 13 connected to a lower part of a body 12 of the jacket leg 11 is inserted into the joint socket 22, and the suction foundation 20 and the substructure 10 are connected by grouting a space between the insertion socket 13 and the joint socket 22.

[0066] As mentioned above, the suction foundation 20 is manufactured as one body and conveyed to a construction site, and is inserted at a position where to be installed. A position and a height of the suction pile 21 are controlled through the suction unit. Further, an upper flange 25 provided to an upper part of the joint socket 22 and a lower flange 15 provided between the body 12 of the jacket leg and the insertion socket 12 are included. These upper flange 25 and the lower flange 15 are in contact with each other during installation.

[0067] Further, a gripper unit (not illustrated) fixing a space between the insertion socket 13 and the joint socket 22 is included so as to prevent relative displacements of the substructure 10 and the suction foundation 20 until grout 30 is hardened.

[0068] That is, the substructure 10 is designed without any separate foundation structure. The insertion socket 13 connectable to the joint socket 22 installed to the head part of the suction pile 21 is installed in a lower part of this substructure 10. Also, in this insertion socket 13, a stud 14 is manufactured in advance to maximize jointability.

[0069] After pre-installing the suction foundation 20 at a position of the seabed where a foundation structure should be installed, the substructure 10 is inserted into and fixed to the upper part of the joint by grouting.

[0070] Further, a hydraulic device such as the gripper unit may be used for fixation in order to prevent relative displacement of the joint until the grout 30 is hardened. As mentioned above, as minimizing the error in the joint, it is easy to apply internal and external grippers, and it is allowable to solve all problems in position errors, obtaining an accurate position of the pile, and disagreement of the heights of the studs, without using the template 3.

MODE FOR INVENTION

[0071] FIG. 14 is a flowchart showing an installation method of an offshore substructure supported by a template-integrated suction foundation according to an embodiment of the present disclosure. Firstly, manufactured is a suction foundation 20 having a plurality of suction piles 21, joint sockets 22 connected to each head part of the suction piles 21, and connecting members 23 connecting spaces between these joint sockets 22 S1.

[0072] After, seating the suction foundation 20 on the seabed 1 where to be constructed, the suction foundation 20 is installed by inserting the suction pile 21 into a position where to be constructed of the seabed 1 S2.

[0073] The substructure 10 is conveyed, and an insertion socket 13 installed to a lower part of a jacket leg 11 of the substructure 10 is inserted inside the joint socket 22 S4. A space between the insertion socket 13 and the joint socket 22 is fixed through a gripper unit in order to prevent relative displacements of the substructure 10 and the suction foundation 20 S5. The insertion socket 13 and the joint socket 22 are connected by grouting 30 a space therebetween S6.

[0074] FIG. 15 is a cross-sectional view showing a suction foundation pre-installed (left hand side) and a state that a substructure is connected to the suction foundation (right hand side), according to an embodiment of the present disclosure.

[0075] As shown in FIG. 15, as applying the suction foundation 20 to pre-piling construction, the suction pile 21 is accurately inserted at a set position without using a template 3. Whereby an error in heights of the studs can be minimized and an error in a joint can be likewise minimized.

[0076] Further, as minimizing the error in the joint, it is easy to apply internal and external grippers, and it is allowable to solve all problems in position errors, obtaining an accurate position of the pile, and disagreement of the heights of the studs, without using the template.