CN105804111B - A kind of Length discrepancy leg offshore wind farm jacket basis and its construction method - Google Patents

Abstract

The invention relates to a foundation of an offshore wind power jacket with unequal length legs and a construction method thereof. The foundation of an offshore wind power jacket with unequal length legs includes at least three main pipe legs of different lengths, and a polygonal shape is adopted between the main pipe legs. distribution, the height difference between each main conduit leg is consistent with the pile top elevation difference between the corresponding pile foundations on the seabed, and any two adjacent main conduit legs are connected by diagonal braces to form an integral lattice jacket foundation. The offshore wind power foundation of the jacket with long and short legs of the present invention is composed of two parts: diagonal braces and unequal long legs, and has the advantages of saving materials, being convenient for construction, adapting to the environment, and the like. Since the main legs of the jacket adopt a unequal-length structure, when the geological conditions change greatly and the driving depth of the piles is different, work such as pile cutting can be avoided, construction is convenient, and material waste is reduced at the same time. In addition, the unequal-length conduit structure can reduce the basic cost and the weight of the jacket itself, and has obvious social and economic benefits.

Description

An offshore wind power jacket foundation with unequal legs and its construction method

technical field

The invention relates to a fan foundation of an offshore wind farm, in particular to an offshore wind power jacket foundation with unequal long legs and a construction method thereof.

Background technique

The foundation of the jacket fan in the offshore wind farm is derived from the jacket structure of the offshore oil platform. In foreign wind farms, the jacket is generally in the form of 4 piles. The jacket foundation adopts a spatial quadrilateral prism structure formed by the interconnection of steel pipes. The four main pipe ends of the foundation structure are provided with sleeves, and the sleeves are connected to the pile foundation. Truss connection and shear plate connection can be used. The overall rigidity of the jacket foundation is large, and it is less affected by environmental loads such as waves and currents, and is suitable for sea areas with large water depths.

The traditional offshore wind power jacket foundation generally adopts the form of equal-length main pipes. When it is applied to the complex geological conditions of the seabed, due to the relatively large distance between the bottom of the main pipes, considering the requirements of construction and other aspects, the depth of pile driving is often different, resulting in The height of the pile top is different, so work such as pile cutting is required. It is difficult to cut piles underwater, and it will increase the construction period and cost, and at the same time, it will cause safety hazards to the jacket foundation.

Contents of the invention

In view of the deficiencies of the prior art, the technical problem to be solved by the present invention is to provide a unequal long-leg offshore wind power jacket foundation with novel design, simple structure, material saving, strong environmental adaptability, convenient construction, low cost and safety and reliability. and its construction method.

In order to solve the above problems, the first technical solution of the present invention is: an offshore wind power jacket foundation with unequal length legs suitable for complex geological conditions on the seabed, including at least three main conduit legs of different lengths, one of the main conduit legs The space adopts a polygonal distribution, and the height difference between each main conduit leg is consistent with the pile top elevation difference between the corresponding pile foundations on the seabed. Any adjacent two main conduit legs are connected by diagonal braces to form a whole lattice conduit base.

Preferably, the diagonal brace is an X-shaped diagonal brace, a K-shaped diagonal brace or a combination of the two.

Preferably, the main conduit leg continues to extend downward along the inclination of the jacket foundation.

Preferably, the included angle between the main conduit leg and the horizontal plane is smaller than the included angle between the side of the jacket foundation and the horizontal plane.

In order to solve the above problems, the second technical solution of the present invention is: a construction method for the foundation of an offshore wind power jacket with unequal long legs, comprising the following steps:

(1) Drive in at least three pile foundations distributed in a polygonal shape at a predetermined position under complex geological conditions on the seabed, and measure the pile top elevation difference between each pile foundation;

(2) According to the pile top elevation difference between each pile foundation, select the same number of main conduit legs but different lengths, and the height difference between each main conduit leg is consistent with the pile top elevation difference between the corresponding pile foundations;

(3) In the factory, polygonal distribution is adopted between the main conduit legs, and any two adjacent main conduit legs are connected by diagonal braces to form a whole lattice jacket foundation;

(4) Transport and hoist the jacket foundation to the predetermined position, connect the lower end of the longer main conduit leg to the pile foundation with a smaller pile top elevation, and connect the lower end of the shorter main conduit leg to the pile with a higher pile top elevation The base corresponds to the connection.

Compared with the prior art, the present invention has the following beneficial effects: Since the jacket adopts the structure of long and short legs, when it is applied to complex seabed geological conditions and the elevation of driven piles is different, it can effectively reduce pile cutting or other equivalent treatment. The workload greatly shortens the construction period, facilitates construction, and reduces material waste. In addition, the unequal-length leg structure can reduce the foundation cost and the weight of the jacket itself, and has obvious social and economic benefits. At the same time, for offshore seabeds with shallow overburden, in order to meet the bearing capacity of the foundation, the pile foundation often needs to be rock-socketed. Compared with the traditional jacket multi-pile foundation, the unequal long-leg offshore wind power jacket foundation can also reduce the construction difficulty and engineering quantity .

Description of drawings

FIG. 1 is a schematic front view of Embodiment 1 of the present invention.

FIG. 2 is a schematic top view of Embodiment 1 of the present invention.

Fig. 3 is a schematic front view of Embodiment 2 of the present invention.

FIG. 4 is a schematic top view of Embodiment 2 of the present invention.

Marks in the figure: 100, 101, 102, 103, 104-main conduit legs, 200-diagonal bracing, 300-pile foundation, SL-sea level, SD-submarine bearing layer.

Detailed ways

In order to make the above-mentioned features and advantages of the present invention more comprehensible, the following specific embodiments are described in detail with reference to the accompanying drawings.

As shown in Figures 1 to 4, an offshore wind power jacket foundation with unequal long legs suitable for complex geological conditions on the seabed includes at least three main conduit legs 100 of different lengths, and polygonal shapes are used between the main conduit legs 100. distribution, the height difference between each main conduit leg 100 is consistent with the pile top elevation difference between the corresponding pile foundations 300 on the seabed, and any adjacent two main conduit legs 100 are connected by diagonal braces 200 to form an integral lattice structure Jacket foundation.

Wherein, the upper part of the jacket foundation is used for connecting the wind tower, and the lower part is used for connecting the pile foundations 300 with different pile top elevations.

Wherein, the installation angle of the main conduit leg 100 at the bottom of the jacket foundation either continues to extend downward along the inclination of the jacket foundation, or the angle with the horizontal plane is smaller than the angle between the side of the jacket foundation and the horizontal plane.

Embodiment 1: As shown in Figures 1-2, the jacket foundation includes three main conduit legs 101, 102, 103 of different lengths, and the three main conduit legs 101, 102, 103 are arranged in a triangle. The included angle between the main conduit legs 101, 102, 103 and the horizontal plane is smaller than the included angle between the side of the jacket foundation and the horizontal plane, and the diagonal brace 200 is an X-shaped diagonal brace.

Embodiment 2: As shown in Figures 3 to 4, the jacket foundation includes four main conduit legs 101, 102, 103, 104 of different lengths, and the four main conduit legs 101, 102, 103, 104 adopt a quadrilateral Distribution, the angle between the main conduit legs 101, 102, 103, 104 and the horizontal plane is smaller than the angle between the side of the jacket foundation and the horizontal plane, and the diagonal brace 200 is a combination of X-shaped diagonal braces and K-shaped diagonal braces.

The main conduit legs of different lengths are set for the foundation of the offshore wind power jacket, instead of directly using the jacket with equal-length legs to support on the piles in the past, the original jacket is composed of two parts with unequal-length legs and corresponding diagonal braces. In actual engineering application, if encountering complex seabed geological conditions and different elevations of the top of the driven pile, the unequal long legs at the bottom of the jacket can be used, so that the number and length of the conduits can be adjusted according to the elevation of the top of the pile driven into the seabed or other needs. Arbitrary adjustment, flexible selection, and reduced consumables. The improved jacket foundation not only saves the steel consumption of the body, but also significantly reduces the workload of foundation construction, shortens the construction period, and has obvious economic benefits.

As shown in Figures 1 to 4, a construction method for the foundation of an offshore wind power jacket with unequal long legs includes the following steps:

(1) At least three pile foundations 300 distributed in a polygonal shape are driven into predetermined positions under complex geological conditions on the seabed, and the pile top elevation differences between the pile foundations 300 are measured;

(2) According to the pile top elevation difference between the pile foundations 300, select the same number of main conduit legs 100 with different lengths, and the height difference between the main conduit legs 100 and the pile top elevation between the corresponding pile foundations 300 poorly consistent;

(3) In the factory, each main conduit leg 100 is distributed in a polygonal shape, and any two adjacent main conduit legs 100 are connected by diagonal braces 200 to form an integral lattice jacket foundation;

(4) Transport and hoist the jacket foundation to the predetermined position, connect the lower end of the longer main conduit leg 100 to the pile foundation 300 with a smaller pile top elevation, and connect the lower end of the shorter main conduit leg 100 to the pile top elevation Large pile foundations 300 correspond to connections.

In step (4), the connection between the main conduit leg 100 and the pile foundation 300 may be connected by flange bolts, and the main conduit leg 100 and the pile foundation 300 are fixedly connected by grouting.

The parts not described in the above embodiments are the same as the prior art. The present invention is not limited to the above-mentioned best implementation mode, and anyone can obtain other various forms of offshore wind power jacket foundations with unequal long legs and construction methods thereof under the enlightenment of the present invention. All equivalent changes and modifications made according to the patent scope of the present invention shall fall within the scope of the present invention.

Claims (2)

1. a kind of Length discrepancy leg offshore wind farm jacket basis suitable for sea bottom complex geological conditions, it is characterised in that：Including At least three main pipe legs different in size are distributed using polygon between the main pipe leg, between each main pipe leg Height of pile top difference between difference in height pile foundation corresponding with seabed is consistent, passes through diagonal brace between two main pipe legs of arbitrary neighborhood Connect integral lattice jacket basis；

More diagonal braces are equipped between two main pipe legs of arbitrary neighborhood, the diagonal brace is connected to form lattice knot with main pipe leg Structure；

The lower part on the jacket basis is set in seawater；

A kind of construction of Length discrepancy leg offshore wind farm jacket basis under sea bottom complex geological conditions includes the following steps：

（1）Precalculated position under sea bottom complex geological conditions is squeezed at least three pile foundations in polygon distribution, is measured It is poor to the height of pile top between each pile foundation；

（2）It is poor according to the height of pile top between each pile foundation, select identical quantity but main pipe leg different in size, Ge Gezhu Height of pile top difference between difference in height and corresponding pile foundation between conduit leg is consistent；

（3）It in factory, is distributed using polygon between each main pipe leg, is passed through between two main pipe legs of arbitrary neighborhood Diagonal brace connects integral lattice jacket basis；

（4）Jacket basis is transported and is lifted to precalculated position, longer main pipe leg lower end and height of pile top is smaller Pile foundation is correspondingly connected with, and the shorter main pipe leg lower end pile foundation larger with height of pile top is correspondingly connected with.

2. Length discrepancy leg offshore wind farm jacket basis according to claim 1, it is characterised in that：The diagonal brace is X-type The combination of diagonal brace, K-type diagonal brace or the two.