JP2022163916A - Method for constructing foundation of on-water structure - Google Patents
Method for constructing foundation of on-water structure Download PDFInfo
- Publication number
- JP2022163916A JP2022163916A JP2021069050A JP2021069050A JP2022163916A JP 2022163916 A JP2022163916 A JP 2022163916A JP 2021069050 A JP2021069050 A JP 2021069050A JP 2021069050 A JP2021069050 A JP 2021069050A JP 2022163916 A JP2022163916 A JP 2022163916A
- Authority
- JP
- Japan
- Prior art keywords
- foundation
- scouring
- water
- floating structure
- constructing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 29
- 238000000034 method Methods 0.000 title claims abstract description 21
- 239000000463 material Substances 0.000 claims abstract description 63
- 238000010276 construction Methods 0.000 claims abstract description 34
- 238000009434 installation Methods 0.000 claims abstract description 15
- 230000035515 penetration Effects 0.000 claims abstract description 4
- 230000002093 peripheral effect Effects 0.000 claims abstract description 3
- 238000009991 scouring Methods 0.000 claims description 68
- 230000002265 prevention Effects 0.000 claims description 36
- 238000007667 floating Methods 0.000 claims description 31
- 230000000149 penetrating effect Effects 0.000 claims description 3
- 238000005536 corrosion prevention Methods 0.000 abstract 5
- 101150080778 INPP5D gene Proteins 0.000 abstract 1
- 238000010248 power generation Methods 0.000 description 9
- 239000004576 sand Substances 0.000 description 7
- 238000011900 installation process Methods 0.000 description 5
- 238000000576 coating method Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 2
- 239000000835 fiber Substances 0.000 description 2
- 229920000728 polyester Polymers 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 239000011440 grout Substances 0.000 description 1
- 229920006306 polyurethane fiber Polymers 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 239000004575 stone Substances 0.000 description 1
- 238000009941 weaving Methods 0.000 description 1
Images
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/727—Offshore wind turbines
Abstract
Description
本発明は水上構造物の基礎の施工方法に関し、特にモノパイル式の洋上風力発電施設等、水底に立設した支柱の上部に上部構造を設置してなる水上構造物の基礎の施工方法に関する。 The present invention relates to a construction method for the foundation of a floating structure, and more particularly to a construction method for the foundation of a floating structure, such as a monopile type offshore wind power generation facility, in which an upper structure is installed on top of a column erected on the bottom of the water.
近年、環境負荷の少ない再生可能エネルギーの供給源として、洋上風力発電施設が多数建設されている。
洋上風力発電施設には、着床式と浮体式があり、着床式には例えばモノパイル式、重力式、ジャケット式、トリポッド式等の種類が存在する。この内、モノパイル式の洋上風力発電施設は、海底に立設した支柱の上部にナセルやブレード等の上部構造を設置してなる。
モノパイル式の洋上風力発電施設は、支柱によって水流に乱れが生ずることにより、支柱の基礎周辺に洗掘が発生する。これは最大で支柱の径の２倍もの深さに達するため、施設の安定性に深刻な影響を与える。
そこで従来技術では、支柱の基礎を捨石や石詰袋体等の洗掘防止工で被覆することで、基礎の洗掘を防いでいる。
洗掘防止工を含めたモノパイル式洋上風力発電施設の施工は、（ａ）海底への支柱の打設、（ｂ）支柱基礎への洗掘防止工の設置、（ｃ）支柱上部への上部構造の設置、の順で行われる（図５）。
この内、（ａ）支柱の打設と、（ｃ）支柱上部への上部構造の設置には、自己昇降式作業台船（Ｓｅｌｆ Ｅｌｅｖａｔｉｎｇ Ｐｌａｔｆｏｒｍ：ＳＥＰ船）やクレーン船等の比較的大型の専用船を使用する。
In recent years, many offshore wind power generation facilities have been constructed as a supply source of renewable energy with low environmental impact.
There are two types of offshore wind power generation facilities: the fixed type and the floating type. The fixed type includes, for example, the monopile type, the gravity type, the jacket type, the tripod type, and the like. Of these, the monopile type offshore wind power generation facilities are constructed by installing superstructures such as nacelles and blades on top of columns erected on the seabed.
In a monopile type offshore wind power generation facility, scouring occurs around the base of the pillars due to turbulence in the water flow caused by the pillars. This can reach depths of up to twice the diameter of the pillars, seriously affecting the stability of the facility.
Therefore, in the conventional technology, scour of the foundation is prevented by covering the foundation of the support with anti-scouring works such as riprap and stone-filled bags.
The construction of monopile offshore wind power generation facilities, including scouring prevention works, consists of (a) placing posts on the seabed, (b) installing scouring prevention works on the post foundations, and (c) installing scouring prevention works on the top of the posts. installation of the structure (Fig. 5).
Of these, (a) placing the pillars and (c) installing the superstructure on the top of the pillars are carried out by using a relatively large special purpose ship such as a self-elevating platform (SEP ship) or a crane ship. use a ship.
従来技術には下記のような問題点がある。
＜１＞洗掘防止工は、支柱の基礎周辺に捨石等を積み上げてなるため、支柱の打設前には施工することができない。一方、支柱を打設すると、水流の乱れにより基礎の洗掘が急速に進むため、打設後は迅速に洗掘防止工を設置する必要がある。このため、複数基の洋上風力発電施設を建設する場合、支柱のみを連続して打設することができず、支柱の打設と洗掘防止工を１基ずつ施工しなければならない。よって、施工効率が非常に悪い。
＜２＞洗掘防止工には専用船は不要であるが、洗掘防止工の前工程である支柱の打設と、後工程である上部構造の設置に専用船を使用し、しかも支柱の打設と洗掘防止工を１基ずつ施工するため、洗掘防止工の施工時間を含めて専用船を施工海域に確保する必要がある。このため、専用船の傭船料や船舶損料が高額になり、施工コストが嵩む上、限られた台数の専用船を他の工事へ配船することができなくなる。
＜３＞洗堀防止工に捨石を用いる場合、捨石を薄層に設置し、敷均す必要があり施工に時間がかかる。このため、作業船の拘束期間が長期に及ぶ。また、捨石の設置時に支柱に損傷を与えるおそれがある。
＜４＞気象、海象等の要因により、支柱の打設後直ちに洗掘対策工の設置ができない場合、支柱の基礎周辺に洗掘が生じ、この洗掘部分を埋め戻すため捨石の分量が増加することで、施工コストが更に嵩む。
The prior art has the following problems.
<1> Since scouring prevention work is made by piling rubble around the base of the support, it cannot be constructed before the support is placed. On the other hand, scouring of the foundation rapidly progresses due to turbulence of water flow when the posts are placed, so it is necessary to quickly install scouring prevention works after the posts are placed. For this reason, when constructing multiple offshore wind power generation facilities, it is not possible to cast only the columns in succession, and it is necessary to construct the columns one by one and prevent scouring. Therefore, construction efficiency is very poor.
<2> A dedicated ship is not required for anti-scouring work. Since one installation and one anti-scouring work will be carried out, it is necessary to secure a dedicated vessel in the construction sea area, including the construction time for the anti-scouring work. As a result, the charter fee for the dedicated vessel and the ship loss fee become high, the construction cost increases, and the limited number of dedicated vessels cannot be allocated to other construction works.
<3> When riprap is used for scouring prevention work, it is necessary to install a thin layer of riprap and spread it evenly, which takes time. For this reason, the work boat is confined for a long period of time. In addition, there is a risk of damage to the pillars during installation of the riprap.
<4> If scouring countermeasures cannot be installed immediately after the installation of pillars due to factors such as weather and sea conditions, scouring will occur around the foundations of the pillars, and the volume of riprap will increase in order to backfill the scouring areas. This will further increase construction costs.
本発明は、上記のような課題を解決可能な、水上構造物の基礎の施工方法を提供することを目的とする。 SUMMARY OF THE INVENTION An object of the present invention is to provide a method of constructing a foundation for a floating structure that can solve the above-described problems.
本発明の水上構造物の基礎の施工方法は、水上構造物の設置場所の水底を、面状体からなる洗掘防止材で被覆する被覆工程と、基礎支柱の下端部を、洗掘防止材を貫通して水底に貫入し、基礎支柱を水底に立設する立設工程と、を備え、洗掘防止材の中央付近に、周辺部より基礎支柱の貫通を容易に構成した脆弱部を設けたことを特徴とする。 The construction method for the foundation of a floating structure according to the present invention comprises a covering step of covering the water bottom at the installation site of the floating structure with an anti-scouring material made of a planar body, and a step of covering the lower end of the foundation support with the anti-scouring material. and a erecting step of penetrating the bottom of the water and erecting the foundation support on the bottom of the water, and providing a weak part near the center of the anti-scouring material so that the foundation support can be easily penetrated from the periphery. characterized by
本発明の水上構造物の基礎の施工方法は、洗掘防止材が、透水性シートであってもよい。 In the construction method for the foundation of a floating structure of the present invention, the anti-scouring material may be a water-permeable sheet.
本発明の水上構造物の基礎の施工方法は、脆弱部が、洗掘防止材に刻設した切込みであってもよい。 In the construction method for the foundation of a floating structure of the present invention, the fragile portion may be a notch formed in the anti-scouring material.
本発明の水上構造物の基礎の施工方法は、脆弱部が、洗掘防止材に刻設した放射状の切込みであってもよい。 In the construction method for the foundation of the floating structure of the present invention, the weakened portion may be a radial cut formed in the anti-scouring material.
本発明の水上構造物の基礎の施工方法は、洗掘防止材が発信機を有し、立設工程において、発信機から得た位置情報に基づいて脆弱部の位置を特定してもよい。 In the construction method for the foundation of a floating structure of the present invention, the anti-scouring material has a transmitter, and in the erecting step, the position of the weak portion may be specified based on the position information obtained from the transmitter.
本発明の水上構造物の基礎の施工方法は、立設工程より後に、基礎支柱の上部に上部構造を設置する設置工程を備えていてもよい。 The method of constructing a foundation for a floating structure according to the present invention may include, after the erecting step, an installation step of installing an upper structure on top of the foundation pillars.
本発明の水上構造物の基礎の施工方法は、上述した構成により以下の効果のうち少なくとも１つを有する。
＜１＞基礎支柱の打設前に洗掘防止材を敷設する工法であるため、基礎支柱の立設に続けて洗掘防止工を行う必要がない。従って、洗掘防止工の設置と基礎支柱の打設とを１基ずつ行う必要がなく、洗掘防止材の敷設と基礎支柱の打設をそれぞれ連続して施工することができる。このため、施工効率が極めて高い。
＜２＞洗掘防止工の設置（被覆工程）を先行し、その後に専用船を用いる立設工程と設置工程を続けて施工するため、専用船の拘束時間が短く、傭船料や船舶損料が比較的安価である。また、専用船の拘束時間が短いため、専用船を他の工事へ配船して有効活用することができる。
＜３＞各工程を複数基連続して施工できるため、例えば気象、海象等の施工条件がよい時期に集中して被覆工程を完了させ、施工条件の悪い季節に上部構造物の組立等の陸上作業を行い、回復後に立設工程及び設置工程を行う、等の柔軟な施工が可能となる。
＜４＞洗掘防止材を吊り込んで海底に敷設するだけで洗掘防止工を設置できるため、施工が容易で作業効率が非常に高い。また、捨石を利用しないため基礎支柱を損傷させるおそれがない。
The method for constructing a foundation for a floating structure according to the present invention has at least one of the following effects due to the configuration described above.
<1> Since it is a construction method in which the anti-scouring material is laid before placing the foundation pillars, it is not necessary to perform scouring prevention work after erecting the foundation pillars. Accordingly, it is not necessary to install the anti-scouring work and place the foundation struts one by one, and the installation of the anti-scouring material and the placement of the foundation struts can be carried out in succession. Therefore, construction efficiency is extremely high.
<2> Installation of anti-scouring work (covering process) is preceded, and then erecting and installation processes using a dedicated vessel are carried out in succession. Relatively inexpensive. In addition, since the dedicated ship is available for a short period of time, it can be used effectively by allocating it to other construction work.
<3> Since each process can be constructed in succession for multiple units, for example, the coating process can be completed intensively when construction conditions such as weather and sea conditions are good, and onshore work such as assembly of superstructures can be completed during the season when construction conditions are bad. Flexible construction is possible, such as performing work and then performing the erecting process and the installation process after recovery.
<4> Since the anti-scouring work can be installed simply by hanging the anti-scouring material and laying it on the seabed, construction is easy and work efficiency is very high. In addition, since rubble is not used, there is no risk of damaging the foundation support.
以下、図面を参照しながら本発明の水上構造物の基礎の施工方法について詳細に説明する。 Hereinafter, the method for constructing the foundation of a floating structure according to the present invention will be described in detail with reference to the drawings.
[補強工法]
＜１＞全体の構成（図１）。
本発明の水上構造物の基礎の施工方法は、被覆工程Ｓ１と、立設工程Ｓ２と、を少なくとも備える。本例では立設工程Ｓ２の後に設置工程Ｓ３を備える。
[Reinforcement method]
<1> Overall configuration (Fig. 1).
The method of constructing a foundation for a floating structure according to the present invention includes at least a covering step S1 and an erecting step S2. In this example, an installation step S3 is provided after the erection step S2.
＜１．１＞水上構造物（図２）。
本発明の施工対象となる水上構造物１は、水底から立設する基礎支柱２０と、基礎支柱２０の上部に設置する上部構造１０と、を備える構造物である。
本例では水上構造物１が、タワーやナセル、ブレード等からなる上部構造１０と、鋼管杭やコンクリート杭からなる基礎支柱２０の組合せからなる、モノパイル式の洋上風力発電設備である例について説明する。
ただし水上構造物１は、洋上風力発電設備に限らず、要は水底に立設した基礎支柱２０の上に上部構造１０を備える構造物であれば、どのような構造物にも適用できる。
<1.1> Water structure (Fig. 2).
A floating structure 1 to be constructed according to the present invention is a structure including a foundation support 20 erected from the bottom of the water and an upper structure 10 installed on top of the foundation support 20 .
In this example, an example will be described in which the floating structure 1 is a monopile type offshore wind power generation facility composed of a combination of a superstructure 10 composed of towers, nacelles, blades, etc., and foundation supports 20 composed of steel pipe piles or concrete piles. .
However, the floating structure 1 is not limited to an offshore wind power generation facility, and can be applied to any structure as long as it has an upper structure 10 on a foundation support 20 erected on the bottom of the water.
＜１．２＞洗掘防止材（図３）。
洗掘防止材Ａは、基礎支柱２０周辺の洗掘を防止するための部材である。
洗掘防止材Ａは、面状の防止材本体Ａ１と、防止材本体Ａ１の中央付近に設けた脆弱部Ａ２と、を少なくとも有する。
防止材本体Ａ１は、水底の起伏に追従可能な柔軟性を備える面状体からなる。
本例では防止材本体Ａ１として、高強度ポリエステル繊維を多重織してなる、正方形の透水性シートを採用する。
防止材本体Ａ１が透水性であるため、洗掘防止材Ａにかかる揚圧力を低減して、洗掘防止材Ａのめくれを防ぐことができる。また、防止材本体Ａ１全体が水を透過するため、水流によるシート周辺部の局所的な洗掘を抑制することができる。
なお、防止材本体Ａ１の素材は高強度ポリエステル繊維に限らず、例えばポリウレタン繊維等であってもよいが、十分な耐久性、引張強度、及び耐摩耗性を備えた素材を採用するのが望ましい。
また、防止材本体Ａ１の形状は正方形に限らず、長方形、円形、その他の多角形であってもよい。
更に、防止材本体Ａ１は透水性シートに限らず、不透水性シート、マット体、板状体等であってもよい。
<1.2> Anti-scouring material (Fig. 3).
The anti-scouring material A is a member for preventing scouring around the foundation support 20 .
The anti-scouring material A has at least a planar anti-scouring material main body A1 and a fragile portion A2 provided near the center of the anti-scouring material main body A1.
The prevention material main body A1 is made of a flexible planar body that can follow the undulations of the bottom of the water.
In this example, a square water-permeable sheet formed by multi-weaving high-strength polyester fibers is used as the prevention material main body A1.
Since the main body A1 of the anti-scouring material A1 is water-permeable, the lifting force applied to the anti-scouring material A can be reduced, and the anti-scouring material A can be prevented from being turned over. In addition, since the entire prevention material main body A1 is permeable to water, it is possible to suppress local scouring of the sheet periphery due to water flow.
The material of the prevention material body A1 is not limited to high-strength polyester fiber, and may be, for example, polyurethane fiber, but it is desirable to adopt a material with sufficient durability, tensile strength, and wear resistance .
Moreover, the shape of the prevention member main body A1 is not limited to a square, and may be a rectangle, a circle, or other polygons.
Furthermore, the prevention material main body A1 is not limited to a water permeable sheet, and may be a water impermeable sheet, a mat body, a plate-like body, or the like.
＜１．３＞脆弱部（図３）。
脆弱部Ａ２は、基礎支柱２０を貫通させるための部分である。
脆弱部Ａ２は、防止材本体Ａ１の中央付近に設ける。
本例では脆弱部Ａ２として、防止材本体Ａ１の中央に刻設した８状の放射状切込みを採用する。ただしこれに限らず、例えば十字状の切込み、円形の部分切込み、Ｖ字状の切込み等であってもよい。
また、脆弱部Ａ２は切込みに限らず、例えば周辺部より厚みが薄い薄肉構造、防止材本体Ａ１の中央に貫通孔を設けて貫通孔を脆弱部材で塞いだ構造、又はこれらの組合せ等であってもよい。要は防止材本体Ａ１上における周辺部より、基礎支柱２０を容易に貫通できる構成であればよい。
<1.3> Weak part (Fig. 3).
The fragile portion A2 is a portion through which the foundation strut 20 is penetrated.
The fragile portion A2 is provided near the center of the prevention material main body A1.
In this example, as the weakened portion A2, eight-shaped radial cuts carved in the center of the prevention material main body A1 are employed. However, it is not limited to this, and may be, for example, a cross-shaped cut, a circular partial cut, a V-shaped cut, or the like.
In addition, the fragile portion A2 is not limited to a notch, and may be, for example, a thin structure having a thickness thinner than that of the peripheral portion, a structure in which a through hole is provided in the center of the prevention material main body A1 and the through hole is closed with a fragile member, or a combination thereof. may What is necessary is just to be the structure which can penetrate the foundation support|pillar 20 easily from the periphery part on prevention material main body A1.
＜２＞被覆工程（図４Ａ）。
被覆工程Ｓ１は、水上構造物１の設置場所の水底を洗掘防止材Ａで被覆する工程である。被覆工程Ｓ１は、例えば以下のように施工する。
クレーン付き台船のクローラクレーンを用いて、洗掘防止材Ａを海底に吊り込み、設置場所に敷設する。
本発明の水上構造物の基礎の施工方法は、面状の洗掘防止材Ａを海底に敷設するだけで洗掘防止工を設置できるため、潜水士による肉体労働が不要であり、施工効率が非常に高い。また、捨石によって基礎支柱２０を損傷させるおそれがない。
また、洗掘防止工である被覆工程Ｓ１を、立設工程Ｓ２の前に行うため、専用船を被覆工程Ｓ１の作業時間の間待機させる必要がない。このため、専用船の拘束時間を短縮して施工コストを節減できる上、台数が限られた専用船を他の工事に有効利用することができる。
<2> Coating step (Fig. 4A).
The covering step S1 is a step of covering the bottom of the water where the floating structure 1 is installed with the anti-scouring material A. As shown in FIG. The covering step S1 is carried out, for example, as follows.
Using a crawler crane of a barge with a crane, the anti-scouring material A is suspended on the seabed and laid at the installation site.
In the construction method of the foundation of the floating structure of the present invention, since the anti-scouring work can be installed only by laying the planar anti-scouring material A on the seabed, manual labor by divers is unnecessary, and the construction efficiency is high. very high. In addition, there is no possibility of damaging the foundation support 20 by rubble.
Moreover, since the covering step S1, which is an anti-scouring work, is performed before the erecting step S2, there is no need to make the dedicated ship stand by during the working time of the covering step S1. As a result, it is possible to reduce construction costs by shortening the time spent on dedicated vessels, and the limited number of dedicated vessels can be effectively used for other construction work.
＜３＞立設工程（図４Ｂ）。
立設工程Ｓ２は、基礎支柱２０を海底に立設する工程である。立設工程Ｓ２は、例えば以下のように施工する。
ＳＥＰ船のクローラクレーンによって、基礎支柱２０を海中に吊り込み、基礎支柱２０の下端部を、洗掘防止材Ａの脆弱部Ａ２に位置合わせして当接させる。
バイブロハンマによって基礎支柱２０の頭部に振動を与えることで、基礎支柱２０の下端部を洗掘防止材Ａの脆弱部Ａ２に貫通させて海底に貫入する。
なお、基礎支柱２０の立設はバイブロハンマに限らず、油圧ハンマによる打設や先端ビットを付設した基礎支柱２０による回転圧入等によってもよい。
本例では脆弱部Ａ２が放射状の切込みであるため、脆弱部Ａ２の貫通によって、脆弱部Ａ２の三角形状の切片が基礎支柱２０と共に海底の砂の中に押し込まれて基礎支柱２０の外周に密着する。これによって、基礎支柱２０の外周と脆弱部Ａ２の隙間からの砂の流失を防ぐことができる。
基礎支柱２０の立設後、基礎支柱２０の頭部に上部構造１０と連結するためのジョイントスリーブを連結する。
本発明の水上構造物の基礎の施工方法は、洗掘防止工である被覆工程Ｓ１を立設工程Ｓ２前に施工するため、従来技術のように基礎支柱２０の立設から洗掘防止工の設置までの間の洗掘が発生しない。
このため、洗掘防止のために、支柱の打設と洗掘防止工の設置を１基ずつ行う必要がなく、複数の基礎支柱２０の打設を連続して行うことができる。
<3> Standing step (Fig. 4B).
The erecting step S2 is a step of erecting the foundation struts 20 on the seabed. The erecting step S2 is performed, for example, as follows.
The crawler crane of the SEP ship suspends the foundation strut 20 into the sea, and aligns the lower end of the foundation strut 20 with the fragile portion A2 of the anti-scouring material A and abuts it.
By vibrating the head of the foundation strut 20 with a vibratory hammer, the lower end of the foundation strut 20 penetrates the fragile part A2 of the anti-scouring material A and penetrates into the seabed.
The erecting of the foundation struts 20 is not limited to the vibratory hammer, but may be driven by a hydraulic hammer or rotational press-fitting by the foundation struts 20 to which a tip bit is attached.
In this example, since the fragile portion A2 is a radial cut, the triangular section of the fragile portion A2 is pushed into the sand of the seabed together with the foundation strut 20 due to the penetration of the fragile part A2, and adheres closely to the outer periphery of the foundation strut 20. do. As a result, sand can be prevented from flowing out through the gap between the outer periphery of the foundation support 20 and the fragile portion A2.
After erecting the foundation strut 20 , a joint sleeve is connected to the head of the foundation strut 20 to connect with the upper structure 10 .
In the construction method of the foundation of the floating structure of the present invention, since the covering step S1, which is a scouring prevention work, is executed before the erecting step S2, the scouring prevention work from the erection of the foundation struts 20 to the scouring prevention work is performed as in the conventional technology. Scouring does not occur until installation.
For this reason, it is not necessary to install one support column and one anti-scouring work for scouring prevention, and a plurality of foundation support columns 20 can be continuously placed.
＜３．１＞洗掘防止材に脆弱部を設けた理由。
本発明の水上構造物の基礎の施工方法は、洗掘防止材Ａの防止材本体Ａ１に脆弱部Ａ２を設けた点に一つの特徴を有する。
防止材本体Ａ１に脆弱部Ａ２を設けない場合、防止材本体Ａ１の貫通に大きな力を要するため施工の難度が上がり、施工性や施工精度が低下する。
また、基礎支柱２０によって押し込まれた防止材本体Ａ１が水底の砂を下向きに押圧することで、基礎支柱２０の周囲の砂が凹状に陥没し、基礎支柱２０の根入れ不足になるおそれがある。
さらに、基礎支柱２０を強力に押し込んで貫通させることで、洗掘防止材Ａの裂け目が大きくなり、基礎支柱２０の外周と裂け目の間から砂が吸い出されやすくなる。
一方、防止材本体Ａ１の中央に最初から貫通孔を設けておけば、防止材本体Ａ１を押し込んで貫通する必要はなくなるが、被覆工程Ｓ１から立設工程Ｓ２までの間に、貫通孔を通じて防止材本体Ａ１下方の砂が吸い出される。
特に水流によって防止材本体Ａ１が揺動してポンプ状に機能することによって、貫通孔から多量の砂が流失するおそれがある。
以上より、本発明の水上構造物の基礎の施工方法は、防止材本体Ａ１に貫通孔ではなく基礎支柱２０の貫通を容易にする脆弱部Ａ２を設けることで、施工性及び施工精度の向上と吸出し防止とを両立させる。
<3.1> The reason why the scouring prevention material is provided with a fragile portion.
One feature of the construction method for the foundation of a floating structure according to the present invention is that the main body A1 of the anti-scouring material A is provided with a fragile portion A2.
If the prevention material main body A1 is not provided with the fragile portion A2, a large force is required to penetrate the prevention material main body A1.
In addition, the prevention material main body A1 pushed in by the foundation support 20 presses the sand on the bottom of the water downward, and the sand around the foundation support 20 sinks into a concave shape, and there is a risk that the foundation support 20 will be insufficiently embedded. .
Furthermore, by strongly pushing the foundation support 20 and penetrating it, the crack of the anti-scouring material A becomes larger, and sand is easily sucked out from between the outer periphery of the foundation support 20 and the crack.
On the other hand, if a through-hole is provided in the center of the prevention material main body A1 from the beginning, it is not necessary to push the prevention material main body A1 to penetrate it. The sand under the material body A1 is sucked out.
In particular, there is a risk that a large amount of sand will be washed away from the through-holes due to the prevention material body A1 swinging due to water flow and functioning like a pump.
As described above, the construction method of the foundation of the floating structure of the present invention improves workability and construction accuracy by providing the fragile portion A2 that facilitates the penetration of the foundation support 20 instead of the through hole in the prevention material main body A1. To achieve both prevention of sucking out.
＜４＞設置工程（図４Ｃ）。
設置工程Ｓ３は、基礎支柱２０の上部に上部構造１０を設置する工程である。設置工程Ｓ３は、例えば以下のように施工する。
ＳＥＰ船のクローラクレーンによって、基礎支柱２０頭部のジョイントスリーブ内に上部構造１０のタワーを鉛直に吊り込み、隙間にグラウト充填して固定する。
続いてタワーの頭部にハブ及びナセルを固定し、ナセルにブレードを取付ける。
なお、上部構造１０の組み立ては上記に限らず、例えばハブ、ナセル、ブレードを予め地組してユニット化し、このユニットを一括してタワー上に固定して組み立ててもよい。
<4> Installation step (Fig. 4C).
The installation step S<b>3 is a step of installing the upper structure 10 on top of the foundation support 20 . Installation process S3 is constructed as follows, for example.
A crawler crane of the SEP ship vertically suspends the tower of the superstructure 10 into the joint sleeve of the base strut 20, and fills the gap with grout to fix it.
The hub and nacelle are then fixed to the head of the tower, and the blades are attached to the nacelle.
The assembly of the upper structure 10 is not limited to the above. For example, the hub, nacelle, and blades may be pre-assembled into a unit, and the unit may be collectively fixed on the tower for assembly.
[水中測位装置を用いる例]
本例では、立設工程Ｓ２において、水中測位装置を用いて脆弱部Ａ２の位置を特定する。
本例では水中測位装置として、船側のトランシーバと洗掘防止材Ａ側のトランスポンダ（発信機Ａ３）の組合せからなるＵＳＢＬ（Ｕｌｔｒａ Ｓｈｏｒｔ Ｂａｓｅ Ｌｉｎｅ）方式水中測位装置を採用する。
ＵＳＢＬ水中測位装置とは、ＧＮＳＳ測位座標に基づいてトランシーバとトランスポンダの相対位置をＵＳＢＬ方式によって三次元測位するシステムである。
防止材本体Ａ１の所定の位置に複数のトランスポンダを付設する。トランスポンダの付設位置は問わないが、複数のトランスポンダの位置から脆弱部Ａ２の位置を特定可能な位置とする（例えば直線上において脆弱部Ａ２を等距離に挟む両位置）。
立設工程Ｓ２において、船上のトランシーバから水中に音響信号を送り、この音響信号に対しトランスポンダが発する応答信号から、トランシーバと複数のトランスポンダとの相対位置を求める。続いて、複数のトランスポンダの相対位置と、防止材本体Ａ１上におけるトランスポンダと脆弱部Ａ２との相対位置から、トランシーバと脆弱部Ａ２の相対位置を求める。
本例では、船上から脆弱部Ａ２の位置を特定することで、基礎支柱２０を脆弱部Ａ２に正確に貫通させることができる。
なお、水中測位装置はＵＳＢＬ方式水中測位装置に限らず、ＳＢＬ（Ｓｈｏｒｔ ｂａｓｅ Ｌｉｎｅ）方式水中測位装置その他各種の水中測位装置を採用することができる。
[Example of using an underwater positioning device]
In this example, in the erecting step S2, the underwater positioning device is used to identify the position of the fragile portion A2.
In this example, as an underwater positioning device, a USBL (Ultra Short Base Line) type underwater positioning device comprising a combination of a transceiver on the ship side and a transponder (transmitter A3) on the anti-scouring material A side is adopted.
The USBL underwater positioning device is a system that three-dimensionally measures the relative positions of a transceiver and a transponder based on GNSS positioning coordinates using the USBL method.
A plurality of transponders are attached to predetermined positions of the prevention material main body A1. Although the transponder may be attached at any position, the positions of the fragile portion A2 can be identified from the positions of the transponders (for example, both positions on a straight line that sandwich the fragile portion A2 at equal distances).
In the erecting step S2, an acoustic signal is sent underwater from the onboard transceiver, and the relative positions of the transceiver and the plurality of transponders are obtained from the response signal emitted by the transponder in response to the acoustic signal. Subsequently, the relative positions of the transceiver and the fragile portion A2 are obtained from the relative positions of the plurality of transponders and the relative positions of the transponders and the fragile portion A2 on the prevention material main body A1.
In this example, by specifying the position of the fragile portion A2 from the ship, the foundation strut 20 can be accurately penetrated through the fragile portion A2.
Note that the underwater positioning device is not limited to the USBL type underwater positioning device, and an SBL (Short base Line) type underwater positioning device and other various types of underwater positioning devices can be employed.
１ 水上構造物
１０ 上部構造
２０ 基礎支柱
Ａ 洗掘防止材
Ａ１ 防止材本体
Ａ２ 脆弱部
Ａ３ 発信機
Ｓ１ 被覆工程
Ｓ２ 立設工程
Ｓ３ 設置工程
1 Floating structure 10 Superstructure 20 Foundation support A Anti-scouring material A1 Main body of anti-scouring material A2 Vulnerable part A3 Transmitter S1 Coating process S2 Erecting process S3 Installation process
Claims (6)
前記水上構造物の設置場所の水底を、面状体からなる洗掘防止材で被覆する被覆工程と、
前記基礎支柱の下端部を、前記洗掘防止材を貫通して水底に貫入し、前記基礎支柱を水底に立設する立設工程と、を備え、
前記洗掘防止材の中央付近に、周辺部より前記基礎支柱の貫通を容易に構成した脆弱部を設けたことを特徴とする、
水上構造物の基礎の施工方法。 A method for constructing a foundation for a floating structure, in which a superstructure is installed on top of a foundation support erected on the bottom of the water, comprising:
a covering step of covering the bottom of the water where the above water structure is installed with an anti-scouring material made of a planar body;
a erecting step of penetrating the lower end of the foundation support post into the bottom of the water through the anti-scouring material to set the foundation support upright on the bottom of the water;
In the vicinity of the center of the scouring prevention material, a fragile portion that facilitates the penetration of the foundation support from the peripheral portion is provided.
A construction method for the foundation of a floating structure.
6. The method for constructing a foundation for a floating structure according to claim 1, further comprising an installation step of installing the upper structure on top of the foundation struts after the erecting step. .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2021069050A JP6960550B1 (en) | 2021-04-15 | 2021-04-15 | Construction method of foundation of floating structure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2021069050A JP6960550B1 (en) | 2021-04-15 | 2021-04-15 | Construction method of foundation of floating structure |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP6960550B1 JP6960550B1 (en) | 2021-11-05 |
| JP2022163916A true JP2022163916A (en) | 2022-10-27 |
Family
ID=78409681
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2021069050A Active JP6960550B1 (en) | 2021-04-15 | 2021-04-15 | Construction method of foundation of floating structure |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP6960550B1 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP7141649B1 (en) | 2021-12-06 | 2022-09-26 | 東亜建設工業株式会社 | Scouring suppression body and scour suppression method |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005023635A (en) * | 2003-07-01 | 2005-01-27 | Shibata Ind Co Ltd | Protection method for bearing ground of ocean structure and protective mat |
| JP2007092406A (en) * | 2005-09-29 | 2007-04-12 | Mitsubishi Heavy Industries Bridge & Steel Structures Engineering Co Ltd | Foundation structure for on-water structure |
| JP2009084804A (en) * | 2007-09-28 | 2009-04-23 | Unitica Fibers Ltd | Scouring prevention mat |
| JP2019027168A (en) * | 2017-07-31 | 2019-02-21 | ダイナガ株式会社 | Building of airtight foundation structure and packing material used therefor |
| JP2019085703A (en) * | 2017-11-01 | 2019-06-06 | 古河機械金属株式会社 | Mining system of seabed deposit, mining machine and diving machine used for mining of the same, and mining method of the same |
| JP2019100070A (en) * | 2017-12-01 | 2019-06-24 | 五洋建設株式会社 | Foundation structure of offshore wind power generation facility, and construction method of the same |
| JP2020041315A (en) * | 2018-09-10 | 2020-03-19 | 鹿島建設株式会社 | Scour preventing construction around pile-shaped body, and construction method of scour preventing construction around pile-shaped body |
-
2021
- 2021-04-15 JP JP2021069050A patent/JP6960550B1/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005023635A (en) * | 2003-07-01 | 2005-01-27 | Shibata Ind Co Ltd | Protection method for bearing ground of ocean structure and protective mat |
| JP2007092406A (en) * | 2005-09-29 | 2007-04-12 | Mitsubishi Heavy Industries Bridge & Steel Structures Engineering Co Ltd | Foundation structure for on-water structure |
| JP2009084804A (en) * | 2007-09-28 | 2009-04-23 | Unitica Fibers Ltd | Scouring prevention mat |
| JP2019027168A (en) * | 2017-07-31 | 2019-02-21 | ダイナガ株式会社 | Building of airtight foundation structure and packing material used therefor |
| JP2019085703A (en) * | 2017-11-01 | 2019-06-06 | 古河機械金属株式会社 | Mining system of seabed deposit, mining machine and diving machine used for mining of the same, and mining method of the same |
| JP2019100070A (en) * | 2017-12-01 | 2019-06-24 | 五洋建設株式会社 | Foundation structure of offshore wind power generation facility, and construction method of the same |
| JP2020041315A (en) * | 2018-09-10 | 2020-03-19 | 鹿島建設株式会社 | Scour preventing construction around pile-shaped body, and construction method of scour preventing construction around pile-shaped body |
Also Published As
| Publication number | Publication date |
|---|---|
| JP6960550B1 (en) | 2021-11-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP2837554A1 (en) | Partially floating marine platform for offshore wind-power, bridges and marine buildings, and construction method | |
| US20160340852A1 (en) | Construction method for fixing hollow column for supporting marine structures and offshore platforms to a seabed | |
| CN105672232A (en) | In-situ test survey platform of shallow sea area and application method | |
| CN109853567B (en) | Pile sinking method for offshore wind power rock-socketed steel pipe pile | |
| CN105386408A (en) | Deep-water bridge pile foundation construction method | |
| JP2012529584A (en) | Offshore support structure and installation method thereof | |
| CN102312442A (en) | Construction method of trestle steel pipe pile foundation | |
| CN103556651A (en) | Precast concrete jacket type offshore wind turbine foundation | |
| CN104196026A (en) | A method for pulling out underwater steel pipe piles for temporary projects of bridges | |
| CN101200898A (en) | Construction method of drilling pile base for bare rock and shallow overburden | |
| CN217580865U (en) | Large-diameter steel casing drilling platform under deep water slope bare rock geological condition | |
| CN105350526A (en) | Method for setting up steel platform | |
| JP2022163916A (en) | Method for constructing foundation of on-water structure | |
| CN201713827U (en) | Fan base structure of offshore wind power station | |
| CN114855865A (en) | Tensioning type fan foundation anchored on rock-based seabed and arrangement method | |
| Malhotra | Design and construction considerations for offshore wind turbine foundations | |
| CN106223355A (en) | A kind of high bearing platform supported on piles in deep water Hold Hoop method has device and the construction method of end steel jacket box | |
| JP7018159B1 (en) | Scourage prevention sheet | |
| CN111980049A (en) | Foundation device of deep riverbed mast type wharf crane and construction method | |
| CN209795746U (en) | novel assembled is tied and is leaned on ship device | |
| US11920559B2 (en) | Floating platform for high-power wind turbines | |
| JP6105044B2 (en) | Partially floating offshore platform for offshore wind power, bridges and offshore structures, and construction method | |
| CN202969333U (en) | Steel truss rock-socketed wharf structure | |
| JP2020128672A (en) | Installation method of mono-pile foundation for offshore wind power generation and mono-pile foundation for offshore wind power generation | |
| CN108018867A (en) | The method that coastal waters beach column foot construction is realized based on trestle method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20210415 |
|
| A871 | Explanation of circumstances concerning accelerated examination |
Free format text: JAPANESE INTERMEDIATE CODE: A871 Effective date: 20210415 |
|
| A975 | Report on accelerated examination |
Free format text: JAPANESE INTERMEDIATE CODE: A971005 Effective date: 20210428 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20210601 |
|
| A521 | Request for written amendment filed |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20210715 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20211005 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20211011 |
|
| R150 | Certificate of patent or registration of utility model |
Ref document number: 6960550 Country of ref document: JP Free format text: JAPANESE INTERMEDIATE CODE: R150 |