AU2013247474A1 - Method of and system for installing foundation elements in an underwater ground formation - Google Patents
Method of and system for installing foundation elements in an underwater ground formation Download PDFInfo
- Publication number
- AU2013247474A1 AU2013247474A1 AU2013247474A AU2013247474A AU2013247474A1 AU 2013247474 A1 AU2013247474 A1 AU 2013247474A1 AU 2013247474 A AU2013247474 A AU 2013247474A AU 2013247474 A AU2013247474 A AU 2013247474A AU 2013247474 A1 AU2013247474 A1 AU 2013247474A1
- Authority
- AU
- Australia
- Prior art keywords
- screen
- ground formation
- wall
- driver
- modulus
- 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.)
- Abandoned
Links
Classifications
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D7/00—Methods or apparatus for placing sheet pile bulkheads, piles, mouldpipes, or other moulds
- E02D7/02—Placing by driving
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
- B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING
- B63B35/00—Vessels or similar floating structures specially adapted for specific purposes and not otherwise provided for
- B63B35/44—Floating buildings, stores, drilling platforms, or workshops, e.g. carrying water-oil separating devices
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D7/00—Methods or apparatus for placing sheet pile bulkheads, piles, mouldpipes, or other moulds
- E02D7/02—Placing by driving
- E02D7/06—Power-driven drivers
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D7/00—Methods or apparatus for placing sheet pile bulkheads, piles, mouldpipes, or other moulds
- E02D7/02—Placing by driving
- E02D7/06—Power-driven drivers
- E02D7/14—Components for drivers inasmuch as not specially for a specific driver construction
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02B—HYDRAULIC ENGINEERING
- E02B17/00—Artificial islands mounted on piles or like supports, e.g. platforms on raisable legs or offshore constructions; Construction methods therefor
- E02B2017/0056—Platforms with supporting legs
- E02B2017/0065—Monopile structures
Abstract
The invention relates to a method of and system for installing a foundation element, in particular a (mono) pile (2), in a hard underwater ground formation (3) by means of a driver (4). The method comprises the steps of placing a foundation element (2) on the underwater ground formation (3), placing a screen (7) for reducing noise input from the driver (4), driving the foundation element (2) into the ground formation (3) by means of the driver (4) while the screen (7) is positioned about the foundation element (2), and attenuating noise transfer from the underwater ground formation (3) to the outer wall (9) of the screen (7) during at least part of the driving.
Description
WO 2013/154428 PCT/NL2013/050263 Method of and system for installing foundation elements in an underwater ground formation The invention relates to a method of installing a foundation element, in particular a (mono)pile, in a hard underwater ground formation by means of a driver, such as an hydraulic driver. The method comprises the steps of placing 5 a foundation element on the underwater ground formation, placing a screen for reducing noise input from the driver into the surrounding water, and driving the foundation element into the ground formation by means of the driver while the screen is positioned about the foundation element. 10 The invention further relates to a system for installing foundation elements. As explained in European patent publication 1 989 358, offshore ramming work is carried out under water to establish foundations, for example, for drilling, platforms 15 and wind turbines. For wind turbines, large monopiles with a diameter of more than four meters are rammed into the seabed. This ramming results in a substantial underwater noise input, which can have a negative impact on marine fauna. To reduce the noise input underwater, in the method 20 and device according to EP 1 989 358, the material that is to be rammed is surrounded by a fixed flooded sleeve. The sleeve advantageously has a sandwich-like structure. In the example shown in Figure 1 of EP 1 989 358, the sleeve has at least one damping guide element for guiding a pile. 25 EP 1 640 508 relates to a guide device for piles, the device having a frame fastened on a ship-jack-up rig for encompassing and guiding a post, when ramming the post in a benthic division. A nozzle assembly of a blowing device, which can be lowered from an upper standby position 30 underneath the frame into an operating position at the benthic division, is attached at the frame. The pile is WO 2013/154428 PCT/NL2013/050263 2 annularly bordered in a blowing operation. The assembly has pipes with exit openings. WO 2010/151121 relates to a device for the passive reduction of the sound vibrations in a liquid resulting from 5 a sound source arranged below the liquid level of a body of water, the device comprising an elongate tube which can be arranged over the sound source, the tube comprising an outer wall and inner wall, wherein the tube is designed to maintain a certain desired pressure in the intermediate 10 space between the inner and outer wall. In this case, the pressure is reduced with respect to the ambient pressure. As a result of the reduced pressure, the sound vibrations will less readily travel to the outside and the noise level in the area around the tube is reduced. "The outer wall and 15 inner wall of the tube can be provided one after the other in the body of water, for example by first anchoring the inner wall into the bottom and then anchoring the outer wall which is arranged around it into the bottom. However, it is also possible to place the tube as a whole, that is to say 20 with the inner and outer wall already assembled to form a single part, on the bottom." It is an object of the present invention to further improve noise mitigation, in particular when driving foundations elements in hard subsea ground formations and/or 25 when the noise mitigation screen is made of a material having a high modulus of elasticity, e.g. in excess of 100 GPa. To this end, the method of the present invention comprises attenuating noise transfer from the (underwater) 30 ground formation to the outer wall of the screen during at least part of the driving, preferably by at least substantially dynamically uncoupling at least the outer wall of the screen from the ground formation. It was found that the medium, typically (sea)water, 35 between the foundation element, e.g. a monopile, and the WO 2013/154428 PCT/NL2013/050263 3 screen is not the only acoustic transfer path and that noise generated by the pile driver is transmitted from the pile to the outer wall of the screen also via the ground formation the screen is resting on or in. This is particularly true 5 when the ground formation comprises hard materials, such as rock, concrete blocks (scour protection) or compacted sand, and/or when the screen is made of a material having a high modulus of elasticity. As noise generated by the pulse-like blows of a pile driver contains a wide spectrum of 10 frequencies, the outer wall of the screen is typically excited at one or more eigenfrequencies, which dampen out relatively slowly. By attenuating noise transfer via the ground formation, such excitation is avoided or at least reduced and overall acoustic radiation is further mitigated. 15 Attenuation is achieved passively e.g. by reducing, relative to prior art methods and systems, the stiffness (modulus) of the interface between the ground formation and the lower end of at least the outer wall of the screen, or actively e.g. by establishing the main eigenfrequencies of 20 the screen and providing means for extinguishing these frequencies in the noise generated by the pile driver. In an embodiment, the lower end of the outer wall of the screen is maintained at a distance from, typically above, the ground formation, e.g. by suspending the outer 25 wall from an inner wall of the screen (if the screen is double walled), from the pile (if the screen is single walled) or from a surface vessel. The distance is preferably in a range from 5 to 200 centimeters, preferably 10 to 100 centimeters, preferably 15 to 70 centimeters. 30 In another embodiment, the screen is at least 50%, preferably at least 70% buoyant, or even has a buoyancy of 100% or more (at 100%, the density of screen equals the density of the (sea)water), in which case the screen floats. In this latter configuration, it is preferred that the 35 screen is held in position by one or more weights on the WO 2013/154428 PCT/NL2013/050263 4 ground formation, such as concrete blocks or a bubble ring resting on the ground formation, and connectors, such as straps or chains, connecting the screen to the blocks or ring. 5 In yet another embodiment, a noise attenuating material, typically in the shape of a ring having a circumference that corresponds to that of the screen, is being positioned between the lower end of the outer wall of the screen and the ground formation. 10 The invention further relates to a system for installing foundation elements, in particular (mono)piles, in a hard underwater ground formation, comprising a driver, a surface vessel, and a screen to be placed about the foundation element to reduce noise input from the driver. 15 The system further comprises means for attenuating noise transfer from the ground formation to the outer wall of the screen during at least part of the driving. In an embodiment, the surface vessel comprises, in addition to a crane for securing the driver, a crane for 20 suspending the screen and maintaining the screen at a distance from the ground formation during at least part of the driving. Note is this respect that known vessels comprise a single crane for handling the pile and screen and for securing the pile driver during operation. 25 In another embodiment, the screen is at least 50%, preferably at least 70% buoyant or even has a buoyancy of 100% or more and to that end e.g. comprises one or more chambers and/or is made from a material having a density lower than that of water. 30 In yet another embodiment, the screen is provided with a support, attached to or separate from the screen, of a noise attenuating material, preferably of a material having a modulus that is lower than the modulus of the material of the outer wall of the screen and lower than the 35 modulus of the underwater ground formation. During driving, WO 2013/154428 PCT/NL2013/050263 5 the support is positioned between the lower rim of the screen and the ground formation. For the sake of completeness, attention is drawn to the following prior art. 5 JP 60-159218 discloses a sound insulator for a pile hammer comprising sound insulating cylinders, which are formed from a resilient material and in the shape of bellows. The sound insulating cylinders are secured around a pile. 10 DE 1 784 396 discloses a pile driving hammer comprising a telescopic sound absorbing sleeve. EP 2 395 156 relates to a method of installing foundation elements, in particular (mono)piles, comprising the steps of placing a foundation element on the underwater 15 ground formation and holding the foundation element in place by means of a gripper mounted on a surface vessel. T.J. Carlson et al., "Hydroacoustic Measurements During Pile Driving at the Hood Canal Bridge, September Through November 2004" discloses a HDPE pipe sleeve that 20 fits over a 24 inch pile and reaches from a point above water to the ground elevation below water. The mentioned sleeve diameter and wall thickness are 34 inch and 1 3/8 inch, respectively. The invention will now be explained in more detail 25 with reference to the Figures, which show a preferred embodiment of the present method and system. Within the framework of the present invention, the words "hard ground formation" refer to formations, natural or artificial, which, at least at the interface with the 30 screen comprise material having a modulus of elasticity in excess of 10 MPa. Typical examples include, but are not limited to, rock (modulus usually in a range from 10 to 90 GPa), densely packed sand (modulus usually 20 to 150 MPa), and so-called scour protection (modulus usually 10 to 90 35 GPa), i.e. rocks, concrete blocks or the like dumped at the WO 2013/154428 PCT/NL2013/050263 6 driving site prior to driving and intended to protect installed foundations element from erosion e.g. by strong currents. Figure 1 is a cross-section of a first embodiment 5 according to the present invention, wherein the noise mitigation screen is suspended from a surface vessel. Figures 2 and 3 are a perspective view and a cross section of a second embodiment according to the present invention, comprising an inflatable cushion. 10 Figure 4 is a perspective view of a third embodiment comprising a floating screen. It is noted that the Figures are schematic in nature and that details, which are not necessary for understanding the present invention, may have been omitted. 15 Figure 1 shows an embodiment of a system 1 according to the present invention for installing a monopile 2 in an underwater ground formation 3, e.g. a seabed. In this example, the monopile 2 has a circular cross-section and a diameter of five meters and is intended to serve, 20 after installation, as the foundation of a wind turbine. The system 1 comprises an hydraulic driver 4 (depicted in Figure 2), e.g. an IHC Hydrohammer S-1800, connected to a power pack on board of a surface vessel, such as a ship 5 or jack-up barge, a driver screen 6 for securely 25 mounting the driver on the monopile and an anvil (hidden from view by the driver screen) for transmitting impact energy from the driver 4 to the monopile. The system further comprises a noise mitigation screen 7, made of e.g. steel, to be placed about the 30 foundation element to reduce. noise input from the driver into the surrounding water. In this example, the screen comprises an inner wall 8 and an outer wall 9, i.e. is double walled, has a circular cross-section and an inner diameter of six meters. The double wall provides one or more WO 2013/154428 PCT/NL2013/050263 7 chambers 10 for air or a porous material and renders the screen 50% buoyant. The upper rim of the screen is provided with a detachable extender, which is used to adjust the effective 5 length of screen to the depth of the water at the location where the foundation element is to be installed. In general, it is preferred that, once in place, the sound-insulating screen extends to above the water level. The ship 5 comprises a first crane 11 to lift and 10 manipulate the monopile 2 and the screen 7 and a second crane (not shown) to secure the hydraulic driver during driving. Installation of a monopile is carried out for instance as follows. The cables of the crane are attached to 15 the upper end of a monopile stored on the deck of the ship and the monopile is lifted overboard, manipulated to an upright position, lowered onto the seabed and, if required by the circumstances, allowed to penetrate the scour protection and possibly the seabed under its own weight. At 20 this stage, the monopile is driven, e.g. by means of a vibratory device, into the seabed to a depth of some meters to further stabilize the monopile. The driver is positioned on top of the monopile and the screen is lifted over the monopile and the driver. 25 Alternatively, the screen is placed and the driver is subsequently placed inside the screen and on top of the pile. In this position, the pile is driven to the required depth. Finally, the driver is removed, the screen lifted over the pile and placed back on deck or into the sea, and 30 installation is completed. In accordance with the present invention, at least during driving, a distance in a range from 20 to 100 centimeters is maintained between the lower rim of the screen and the seabed, thus dynamically uncoupling the two. 35 As a result, substantially no noise or vibrations are WO 2013/154428 PCT/NL2013/050263 8 transmitted to the screen via the seabed. Although noise leaks through the annular opening resulting from the distance, the energy of this noise is significantly less that that of the noise generated by excitation of the outer 5 wall of the screen by the seabed, i.e. overall acoustic radiation is further mitigated. In the embodiment shown in Figures 2 and 3, the screen 7 rests on an annular inflated cushion 12, which has a modulus of elasticity that is at least one order of 10 magnitude smaller than the modulus of the seabed and the modulus of the screen. Thus, the cushion effectively attenuates at least the higher frequencies, i.e. serves as a low pass filter. Figure 4 shows a system comprising a screen 7 15 having a buoyancy in excess of 100%, e.g. achieved by spacing the inner and outer walls of screen farther apart, and a weight 13 for holding the floating screen upright and spaced from the seabed over a distance in a range from 20 to 100 centimeters. In this example, the weight is provided by 20 a ring for generating a bubble screen inside the double walled screen 7, i.e. the outer diameter of the ring is smaller than the inner diameter of the buoyant screen. The screen is attached to the ring by means of straps 14. The invention is not restricted to the embodiment 25 described above and can be varied in numerous ways within the scope of the claims. For instance, the outer wall of the screen can be suspended from the inner wall of the screen (resting on the ground formation), e.g. by interconnections between the inner and outer walls. It is preferred that such 30 interconnections are made of or provided with a dampening material.
Claims (15)
1. Method of installing a foundation element, in particular a (mono)pile (2), in a hard underwater ground formation (3) by means of a driver (4), comprising the steps of 5 placing a foundation element (2) on the underwater ground formation (3), placing a screen (7) for reducing noise input from the driver (4), driving the foundation element (2) into the ground 10 formation (3) by means of the driver (4) while the screen (7) is positioned about the foundation element (2), and characterized by attenuating noise transfer from the ground formation (3) to the outer wall (9) of the screen (7) during 15 at least part of the driving.
2. Method according to claim 1, comprising at least substantially dynamically uncoupling at least the outer wall (9) of the screen (7) from the ground formation (3).
3. Method according to claim 2, wherein at least 20 the lower end of the outer wall (9) of the screen (7) is maintained at a distance from the ground formation (3).
4. Method according to claim 3, wherein the screen (7) is suspended.
5. Method according to claim 3 or 4, wherein the 25 screen (7) is at least 50% buoyant.
6. Method according to claim 5, wherein the screen (7) floats and is held in position by one or more weights (13) on the ground formation (3).
7. Method according to any one of the preceding 30 claims, wherein a noise attenuating material (12) is being positioned between the ground formation (3) and the lower end of the outer wall (9) of the screen (7). WO 2013/154428 PCT/NL2013/050263 10
8. Method according to claim 7, wherein the modulus of the material is lower than the modulus of the material of the outer wall (9) of the screen (7) and lower than the modulus of the underwater ground formation (3). 5
9. System (1) for installing foundation elements, in particular (mono)piles (2), in a hard underwater ground formation (3), comprising a driver (4), a surface vessel (5), and a screen (7) to be placed about the foundation element (2) to reduce noise input from the driver (4), 10 characterised by means (12; 13, 14) for attenuating noise transfer from the ground formation (3) to the outer wall (9) of the screen (7) during at least part of the driving.
10. System (1) according to claim 9, wherein the surface vessel (5) comprises, in addition to a crane for 15 securing the driver (4) during driving, a crane (11) for maintaining the screen (7) at a distance from the ground formation (3) during at least part of the driving.
11. System (1) according to claim 9 or 10, wherein the screen (7) is at least 50% buoyant. 20
12. System (1) according to claim 11, wherein the screen (7) comprises at least an inner wall (8) and an outer wall (9).
13. System (1) according to claim 12, wherein the screen (7) has a buoyancy in excess of 100% and the system 25 (1) further comprises a weight (13) for maintaining the floating screen (7) upright.
14. System (1) according to any one of claims 9-13, wherein the screen (7) is provided with a support (12) of a noise attenuating material to be positioned between the 30 lower rim of the screen (7) and the ground formation (3).
15. System (1) according to claim 14, wherein the modulus of the support (12) is lower than the modulus of the material of the outer wall (9) of the screen (7) and lower than the modulus of the underwater ground formation (3).
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
NL2008625A NL2008625C2 (en) | 2012-04-11 | 2012-04-11 | Method of and system for installing foundation elements in an underwater ground formation. |
NL2008625 | 2012-04-11 | ||
PCT/NL2013/050263 WO2013154428A2 (en) | 2012-04-11 | 2013-04-10 | Method of and system for installing foundation elements in an underwater ground formation |
Publications (1)
Publication Number | Publication Date |
---|---|
AU2013247474A1 true AU2013247474A1 (en) | 2014-10-16 |
Family
ID=48237202
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
AU2013247474A Abandoned AU2013247474A1 (en) | 2012-04-11 | 2013-04-10 | Method of and system for installing foundation elements in an underwater ground formation |
Country Status (7)
Country | Link |
---|---|
US (1) | US20150078836A1 (en) |
EP (1) | EP2847389A2 (en) |
JP (1) | JP2015513022A (en) |
CN (1) | CN104271843A (en) |
AU (1) | AU2013247474A1 (en) |
NL (1) | NL2008625C2 (en) |
WO (1) | WO2013154428A2 (en) |
Families Citing this family (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NL2013349B1 (en) * | 2014-08-21 | 2016-09-23 | Ihc Holland Ie Bv | Method of and system for installing foundation elements in an underwater ground formation. |
US20170291882A1 (en) * | 2014-10-01 | 2017-10-12 | Apotex Inc. | Solid Forms of Mirabegron |
NL2014069B1 (en) * | 2014-12-29 | 2016-10-12 | Ihc Holland Ie Bv | Noise mitigation system |
JP6863757B2 (en) * | 2017-01-31 | 2021-04-21 | 旭化成建材株式会社 | Noise reduction device |
CN108571019B (en) * | 2017-12-06 | 2023-11-24 | 湖南工程学院 | Scour prevention device for offshore wind power pile |
PL3517479T3 (en) * | 2018-01-30 | 2022-11-07 | Deme Offshore Be N.V. | Device and method for providing a sizeable, slender object with a longitudinal direction into an underwater bottom |
JP6826266B2 (en) * | 2019-05-23 | 2021-02-03 | 中村物産有限会社 | Monopile foundation auxiliary structure for offshore wind turbines and monopile foundation auxiliary structure for offshore wind turbines |
JP7284723B2 (en) * | 2020-01-31 | 2023-05-31 | 五洋建設株式会社 | Underwater noise suppression structure and suppression method |
JP7245196B2 (en) * | 2020-05-29 | 2023-03-23 | 五洋建設株式会社 | Underwater noise suppression composition, manufacturing method thereof, underwater noise suppression structure and underwater noise suppression method using the same |
Family Cites Families (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE1784396B1 (en) | 1968-08-03 | 1971-07-01 | Cordes Hugo Dipl Ing | Ram hammer with sound-absorbing jacket |
FR2184147A5 (en) * | 1972-05-08 | 1973-12-21 | Gem | |
DE2237133C3 (en) * | 1972-07-28 | 1975-04-30 | Cordes, Hugo, Dipl.-Ing., 2000 Hamburg | Ram hammer with sound-absorbing jacket |
JPS60159218A (en) | 1984-01-28 | 1985-08-20 | Ishikawajima Harima Heavy Ind Co Ltd | Sound-insulator for pile hammer |
DE102004043128A1 (en) | 2004-09-03 | 2006-03-09 | Menck Gmbh | Post guiding device for ramming offshore windmill foundation, has nozzle assembly of blowing device, which can be lowered from upper standby position underneath frame into operating position at benthic division, is attached at frame |
DE102006008095A1 (en) | 2006-02-20 | 2007-08-23 | Menck Gmbh | Method and device for environmentally friendly propulsion under water |
NL2003073C2 (en) * | 2009-06-23 | 2010-12-27 | Ihc Holland Ie Bv | DEVICE AND METHOD FOR REDUCING SOUND. |
US9617702B2 (en) * | 2010-01-19 | 2017-04-11 | University Of Washington Through Its Center For Commercialization | Pile with sound abatement |
EP2395156A1 (en) | 2010-06-08 | 2011-12-14 | IHC Holland IE B.V. | Method of and system for installing foundation elements in an underwater ground formation |
PL2744946T3 (en) * | 2011-08-19 | 2016-06-30 | Abb Research Ltd | A method and an apparatus for attenuating pressure pulses |
-
2012
- 2012-04-11 NL NL2008625A patent/NL2008625C2/en not_active IP Right Cessation
-
2013
- 2013-04-10 CN CN201380023463.3A patent/CN104271843A/en active Pending
- 2013-04-10 AU AU2013247474A patent/AU2013247474A1/en not_active Abandoned
- 2013-04-10 US US14/391,357 patent/US20150078836A1/en not_active Abandoned
- 2013-04-10 EP EP13720105.9A patent/EP2847389A2/en not_active Withdrawn
- 2013-04-10 WO PCT/NL2013/050263 patent/WO2013154428A2/en active Application Filing
- 2013-04-10 JP JP2015505677A patent/JP2015513022A/en active Pending
Also Published As
Publication number | Publication date |
---|---|
WO2013154428A3 (en) | 2014-05-08 |
CN104271843A (en) | 2015-01-07 |
EP2847389A2 (en) | 2015-03-18 |
US20150078836A1 (en) | 2015-03-19 |
NL2008625C2 (en) | 2013-10-15 |
JP2015513022A (en) | 2015-04-30 |
WO2013154428A2 (en) | 2013-10-17 |
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Legal Events
Date | Code | Title | Description |
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MK1 | Application lapsed section 142(2)(a) - no request for examination in relevant period |