Abstract
An offshore structure (1) with tubular braces (110) that are joined by joints (125) at nodes (120). The tubular braces (110) may be made of steel. The joint (125) is formed by means of casted concrete or grout in a receiving joint volume (150) in one or both of the braces (110). Also disclosed is a a keel structure formed by braces (110) and joints (125) as outlined and a combination of a wind turbine and such offshore structure (1).
Claims
1. An offshore structure (100) comprising at least two tubular braces (110A, 110B) with end parts (112A, 112B) of the braces (110A, 110B) joined by a joint (125) at a node (120) of the structure, wherein the tubular braces (110A, 110B) are optionally made of steel, and wherein the joint (125) is formed by means of hardened casting material, for example concrete or grout, in a receiving joint volume (150) in one or both end parts (112A, 112B) of the braces (110A, 110B) that form the node (120).
2. Structure according to claim 1, wherein the node (120) comprises a joint member (111) different from the braces (110A, 110B), and wherein each end part (112A, 112B) has a receiving joint volume (150A, 150B) inside which a respective section of the joint member (111) is received for connecting the end parts (112A, 112B) of the braces (110A, 110B) at the node (120) by the joint member (111), and wherein the volumes (150A, 150B) between the joint member (111) and the respective end parts (112A, 112B) are filled with the casting material, for example concrete or grout.
3. Structure (100) according to claim 2, wherein the joint member (111) has two joint ends (135A, 135B) and is angled according to the angle required for insertion of the two joint ends (135A, 135B) into the end parts (112A, 112B) of the braces (110A, 110B) at the respective node (120).
4. Structure (100) according to claim 3, wherein each joint ends (135A, 135B) that are inside the end parts (112A, 112B) are coaxial with the respective end part (112A, 112B).
5. Structure (100) according to claim 3 or 4, wherein the joint member is piecewise linear angled with the two linear joint ends (135A, 135B) having an angle in between which is fitting the angle between the end parts (112A, 112B).
6. Structure (100) according to claim 2, wherein the joint member (111) is straight and extends laterally through the end parts (112A, 112B) at the node (120) and wherein the cast material is provided between an outer side of the joint member (111) and an inner side of the end parts (112A, 112B).
7. Structure according to any one of the claims 2-6, wherein the structure (100) comprises at least three tubular braces (110A, 110B) arranged as a polygon with end parts (112A, 112B) of the braces (110A, 110B) joined at the node (120) and at further nodes of the polygon by the joint member (111).
8. Structure (100) according to claim 7, wherein the polygon is an equilateral triangle with three braces (110A, 110B, 110C) forming the triangle, the three braces being joined by the joint member (111) pairwise at the nodes (120).
9. Structure (100) according to claim 2, wherein the structure (100) comprises three tubular braces (110A, 110B, 110C) arranged as an equilateral triangle with end parts (112A, 112B, 112C) of the braces (110A, 110B, 110C) joined pairwise by the joints (125) at the node (120) and at two further nodes, wherein the joint member (111) is straight and extends laterally through two adjacent end parts (112A, 112B) of a pair of braces (110A, 110B) at the node (120), wherein a central axis of the joint member (111) has an angle of 60 degrees with the central axes of each of the two braces (110A, 110B) at the node (120), wherein the cast material is provided between an outer side of the joint member (111) and an inner side of the end parts (112A, 112B).
10. Structure (100) according to claim 9, wherein adjacent end-parts (112A, 112B) at the node (120) are formed complementary and abutting each other along an edge region (113), and wherein the straight joint member (111) is inserted into the abutting complimentary brace end parts (112A, 112B) and joined to the brace end-parts (112A, 112B) by the casting material.
11. The structure (1) according to any one of the claims 2-10, wherein the joint member (111A) is internally and/or externally for part of its length fitted with shear keys (197) in the receiving joint volume (150A, 150B) in the end part (112A, 112B).
12. The structure (1) according to any one of the preceding claims, wherein the casting material comprises cement.
13. The structure according to any one of the preceding claims, wherein the structure is a floating offshore structure.
14. The structure according to any one of the preceding claims, in combination with an offshore wind turbine, wherein the wind turbine is supported by the structure.
15. Use of a structure according to any one of the preceding claims for supporting an offshore wind turbine.
Description
BRIEF DESCRIPTION
[0086] Some of the embodiments will be described in detail, with references to the following Figures, wherein like designations denote like members, wherein:
[0087] FIG. 1 illustrates a structure with a grouted joint at a node;
[0088] FIG. 2 illustrates a brace inserted into a receiving volume of another brace;
[0089] FIG. 3 illustrates a joint member inserted into a receiving volume of respective braces;
[0090] FIG. 4A illustrates aspects of brace end fittings;
[0091] FIG. 4B illustrates aspects of brace end fittings FIG. 5 illustrates aspects of a brace fitted with reinforcement bars;
[0092] FIG. 6 illustrates further aspects of a brace fitted with reinforcement bars;
[0093] FIG. 7 illustrates a joint with two braces fitted with reinforcement bars;
[0094] FIG. 8A illustrates further aspects of a brace fitted with reinforcement bars in an open partial view from one side and from another side;
[0095] FIG. 8B illustrates further aspects of a brace fitted with reinforcement bars in an open partial view from one side and from another side;
[0096] FIG. 9 illustrates a coaxial arrangement of a brace end and a receiving volume;
[0097] FIG. 10 illustrates a section with shear keys;
[0098] FIG. 11A illustrates a keel structure with grouted joints formed by a thin end-part of one brace inserted into a thick end-part of another brace in top view and perspective view;
[0099] FIG. 11B illustrates a keel structure with grouted joints formed by a thin end-part of one brace inserted into a thick end-part of another brace in top view and perspective view;
[0100] FIG. 12A illustrates a keel structure with grouted joints formed by a joint pipe inserted into complimentary brace ends in top view and perspective view;
[0101] FIG. 12B illustrates a keel structure with grouted joints formed by a joint pipe inserted into complimentary brace ends in top view and perspective view;
[0102] FIG. 13A illustrates a keel structure with grouted joints formed by a joint pipe inserted into brace ends in top view and perspective view;
[0103] FIG. 13B illustrates a keel structure with grouted joints formed by a joint pipe inserted into brace ends in top view and perspective view;
[0104] FIG. 14A illustrates a keel structure with grouted joints formed by a bent joint pipe inserted into the very end of braces in perspective view and enlarged partial view; and
[0105] FIG. 14B illustrates a keel structure with grouted joints formed by a bent joint pipe inserted into the very end of braces in perspective view and enlarged partial view.
LIST OF REFERENCE NUMBERS
[0106] Item No [0107] 100 Structure [0108] 105 Support column [0109] 110 Brace [0110] 111 Joint member [0111] 112 Brace end/end-part of brace [0112] 113 Abutting edges of complimentary end parts [0113] 115 Thin end-part of brace/male part [0114] 116 Thick end-part of brace/female part [0115] 117 Through part [0116] 118 Inner tube [0117] 119 Outer tube [0118] 120 Node [0119] 125 Joint [0120] 130 Joint pipe [0121] 132 Bent joint pipe or joint member [0122] 135 Joint end [0123] 136 Flange [0124] 137 L-Flange [0125] 138 T-Flange [0126] 140 Reinforcement bars [0127] 142 Bolts [0128] 150 Receiving joint volume [0129] 152 Separator [0130] 155 Tubular section [0131] 160 Pre-cast bushing [0132] 165 Pre-cast sleeve [0133] 190 Concrete [0134] 191 Grouting cement [0135] 192 Reinforced concrete [0136] 195 Grouted joint [0137] 196 Concrete section [0138] 197 Sheer keys [0139] 200 Offshore structure [0140] 300 Keel Structure
DETAILED DESCRIPTION
[0141] FIG. 1 illustrates a structure 100 comprising tubular braces 110A, 110B joined at nodes 120 by a joint 125. The braces are straight, tubular braces 110A, 110B and made of steel. The structure 100 is illustrated as a supporting structure with feet at respective nodes 120. A support member 105 is provided on the support structure 100, for example for supporting a wind turbine.
[0142] As explained in more detail below, the joint 125 is formed by casted material, for example concrete or grout, in a receiving joint volume in one or both of the braces 110A, 110B.
[0143] FIG. 2 illustrates a brace 110A inserted into a receiving volume 150 of another brace 110B. The receiving volume 150 is filled with the casting material, for example concrete or grout. In this case, the receiving volume 150 is defined by the tubular shape of the brace 110B and the separators 152, which are divider walls or plates. The separators 152 may be located according to the actual need of structural strength and/or weight. Here, the joint 125 comprises an end-part 112A of the brace 110A inserted into the receiving joint volume 150 of the other brace 110B. For high connection strength, not only the receiving volume 150 but also the end part 112A is filled with the casted concrete or grout up to the separator 152A of the end part 112A. For additional strength, a laterally inwards and outwards extending end-flange 138, forming a cross sectional shape of the letter “T”, is provided at the very end of the end part 112A. The flange 138 could have other shapes, as also explained below.
[0144] FIG. 3 illustrates an angled joint member 110 inserted into receiving volumes 150A, 150B of respective braces 110A, 110B. The joint 125 is formed of end parts 112A, 112B of respective two braces 110A, 110B, each end part 112A, 112B configured with a receiving joint volume 150A, 150B inside which a joint member 111 is received. The volumes 150A, 150B between the end parts 112A, 112B and the joint member 111 are filled with a casting material, such as polymer, grout, or concrete. The joint member 111 is V-shaped and angled according to the angle required for insertion of the two joint ends 135A, 135B coaxially into the end parts 112A, 112B of the respective braces 110A, 110B.
[0145] FIGS. 4A and B illustrate aspects of joints 125 end fittings. The end-part 112A of the brace 110A that is inserted into a receiving joint volume 150 in another brace 110B is fitted with a laterally inwards or outwards extending end flange, forming an L-flange, 137 (FIG. 4A) or with a laterally inwards and outwards extending end flange, forming a T-flange 138 (FIG. 4B). The end-part 112A of the inserted brace 110A is hollow and with an opening at the very end so that the hollow end part 112A forms a further volume to be filled with concrete together with the receiving volume 150 of the other brace 110B.
[0146] FIG. 5 illustrates aspects of a brace 110A, the end-part 112A has an end flange 138 fitted with reinforcement bars 140 for forming a reinforced concrete joint. The end-part 112A of the brace 110A that is inserted into a receiving joint volume 150 in the other brace 110B is surrounded by multiple reinforcement bars 140 that extend into the receiving volume 150. Whereas the end flange 138 increases the stability of the joint 125 in the axial direction, the bars 140 increase the stability in the rotational direction about the central axis of the brace 110A. As illustrated, the multiple reinforcement bars 140 projects further into the receiving joint volume 150 in the other brace 110B than the end-part 112A of the inserted brace 110A.
[0147] FIG. 6 illustrates further aspects of a brace 110A fitted with reinforcement bars 140.
[0148] Here, the end-part 112A of the brace 110A that is inserted into the receiving joint volume 150 in another brace 110B is internally and externally for part of its length fitted with a pre-cast bushing 160 and sleeve 165 comprising reinforced concrete. Here, the end-part 112A of the inserted brace 110A has a separator 152A at the very end of the brace 110A so that the casting material is not entering the end part 112A.
[0149] FIG. 7 illustrates a joint 125 with two braces 110AI, 110AII each fitted with respective reinforcement bars 1401, 14011 extending into a receiving volume 150 of a receiving brace 110B. The reinforcement bars 1401, 14011 are fitted in respective flanges 137 internally in the braces 110AI, 110AII The reinforcement bars 1401, 14011 are adjusted according to the needed geometry, for example for symmetrical forces.
[0150] FIG. 8 illustrates further aspects of a brace 110A fitted with reinforcement bars 140 in what might be considered a hybrid version of a grouted joint 125. In this case, an inner tube 118 and an outer tube 119 are arranged and fixed to the receiving brace 110B, which has a thicker wall material than the brace 110A that is inserted in between the inner tube 118 and the outer tube 119. Reinforcement bars 140 are provided at an angle in parallel to the tubes 118, 119. The thinner brace 110A to be inserted is fitted with a flange 138 and there is a co-operating flange 136 in the receiving volume 150. The reinforcement bars 140 and one or both of the flanges 136, 138 may be fixed or adjusted by bolts and nut connections where the bolts constitute the reinforcement bars 140.
[0151] FIG. 9 illustrates a coaxial arrangement of a brace 110A end part 112A inserted into a receiving volume 150 formed in a receiving brace 110B. The receiving joint volume 150 is formed by a tubular section 155, e.g., formed by steel or concrete, that functions as a sleeve and is generally coaxial with the end-part 112A of the brace 110A that is inserted into the receiving joint volume 150 in the receiving tubular section 155 of the receiving brace 110B.
[0152] In continuation of FIG. 9, FIG. 10 illustrates a concrete section 196 with shear keys 197. The end-part 112A that is inside the tubular section 155 is fitted with shear keys 197.
[0153] FIGS. 11, 12, 13 and 14 illustrate a structure 100 comprising three braces 110A, 110B, and 110C that are numbered according to being joined at respective nodes 120 by joints 125. The joints 125 are formed by casted concrete or grout (not shown) in respective receiving joint volumes in the braces 110A, 110B, 110C as explained above.
[0154] For example, such structure 100 is intended to be a keel structure for a floating off-shore structure and to have negative buoyancy. Alternatively, or additionally, such structure principle is used as part of a floating frame, optionally with such keel structure.
[0155] The form of the structure is a triangle. The structure is here formed by identical braces 100 and identical joints 125 at respective nodes 120.
[0156] FIG. 11A illustrates, a top view and FIG. 11B a perspective view of a structure 100 with braces 110A, 110B, 110C joined at nodes 120 as grouted joints 125 formed by a narrow end-part 112A of a first brace 110A inserted into a thicker end-part 112B of another brace 110B. This system relates also to the principles explained in FIGS. 2, 4-6, and 8-10.
[0157] FIG. 12 and FIG. 13 illustrate structures 100 with a joint 125 formed of a joint member 111 at brace end-parts 112A, 112B of respective two braces 110A, 110B at each node 120 and each end-part 112A, 112B configured with a receiving joint volume. In this case, the end part 112A, 112B of two adjacent braces at a node 120 are configured to receive a joint member 111, such as a joint pipe 130, and the receiving joint volumes 150A, 150B are filled with concrete 190.
[0158] FIG. 12 specifically illustrates nodes 120 where the respective brace end-parts 112A, 112B are formed complementary to interface along edges 13 against each other and a joint member 111, such as a joint pipe 130, is inserted laterally to the end-parts 112A, 112B and joined by casting, for example grouting, as outlined above. The casted, for example grouted, joints 125 are formed by a joint member 111 inserted laterally into the complimentary brace end part 112A, 112B. As the triangle is an equilateral triangle, the joint member 111 has an angle of 60 degrees with the braces adjacent 110.
[0159] FIG. 13 specifically illustrates three nodes 120 in a triangular structure with casted, for example grouted, joints formed by a joint member 111, such as a joint pipe 130, inserted laterally into the brace end parts 112A, 112B of two braces 110A, 110B at each node 120. As the triangle is an equilateral triangle, the joint member 111 has an angle of 60 degrees with the braces adjacent 110.
[0160] FIG. 14 illustrates a structure with joints 125 formed at respective nodes 120 and formed by an angled joint member 111, such as a joint pipe 130, inserted into the end parts 112A, 112B of the braces 110A, 110B. The joint member 111 is angled and provided with joint ends 135A, 135B that are inserted coaxially into the end parts 112A, 112B, where a casting material, such as grout 190, is provided in the receiving joint volumes 150 between the outer wall of the joint ends 135A, 135B and the inner wall of the end parts 112A, 112B at the narrowing ends of the respective braces 110A, 110B, as illustrated. The angled join member 111, such as joint pipe, is shown largely as a “V-shaped” joint member 111 corresponding to the triangular shape of the structure 100. The joint member 111 is shaped as piecewise linear. The shape is similar to a boomerang shape.
[0161] Although the present invention has been disclosed in the form of embodiments and variations thereon, it will be understood that numerous additional modifications and variations could be made thereto without departing from the scope of the invention.
[0162] For the sake of clarity, it is to be understood that the use of “a” or “an” throughout this application does not exclude a plurality, and “comprising” does not exclude other steps or elements. The mention of a “unit” or a “module” does not preclude the use of more than one unit or module.
