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EP-3914778-B1 - PILE DRIVING METHODS AND SYSTEMS FOR DRIVING A PILE

EP3914778B1EP 3914778 B1EP3914778 B1EP 3914778B1EP-3914778-B1

Inventors

  • ROMEIJN, ERIC

Dates

Publication Date
20260506
Application Date
20200121

Claims (15)

  1. A pile driving system for driving a pile (1), e.g. a hollow and open ended pile, e.g. a large diameter pile having an outer diameter of at least 5 meters, e.g. a monopile of an offshore wind turbine, into the soil, e.g. into the seabed, which pile driving system (7) comprises: - a drive head member (8) that is configured to engage the pile (1), e.g. is configured to be arranged on a top end of the pile (1), e.g. the drive head member (8) having a mass of at least 100 tonnes, e.g. at least 250 tonnes, e.g. of more than 500 tonnes, - a solid mass drop weight assembly (10) comprising a support structure (11) and comprising solid drop weight elements (12a, 12b, 12c, 12d, 12s) supported by said support structure (11), preferably the solid drop weight elements being composed of steel elements, e.g. stackable steel elements, which drop weight elements have a total mass of more than 500 tonnes, e.g. more than 1000 tonnes, e.g. more than 2000 tonnes, which drop weight assembly (10) is vertically mobile relative to, e.g. above, the drive head member (8), - a lift system (20), preferably arranged between the drive head member (8) and the drop weight assembly (10), that is configured to bring the drop weight assembly (10) into an initial height position relative to the drive head member (8), - a quick release mechanism (25) adapted to effect quick release of the lift system (20) so that the drop weight assembly (10) falls down from said initial height position, - an energy transfer assembly (30) configured for transfer of energy from the falling drop weight assembly (10) to the drive head member (8), wherein, for driving the pile (1) into the soil, the drop weight elements (12a, 12b, 12c, 12d, 12s) are configured to be loaded onto the support structure (11) to set a desired total mass of the drop weight assembly (10), wherein the pile driving system is operable in a repeated cycle wherein: - the drop weight assembly (10) is lifted by means of the lift system (20) into a desired initial height position, - the quick release mechanism (25) is operated to effect quick release of the lift system (20) so that the drop weight assembly (10) falls down from said initial height position towards the drive head member (8), and wherein energy from the falling drop weight assembly (10) is transferred by said energy transfer assembly (30) to the drive head member (8) and thereby to the pile (1), e.g. to the top end of the pile (1), so that the pile (1) is driven deeper into the soil.
  2. A pile driving system for driving a pile (1), e.g. a hollow and open ended pile, e.g. a large diameter pile having an outer diameter of at least 5 meters, e.g. a monopile of an offshore wind turbine, into the soil, e.g. into the seabed, which pile driving system (7) comprises: - a drive head member (8) that is configured to engage the pile (1), e.g. is configured to be arranged on a top end of the pile (1), e.g. the drive head member (8) having a mass of at least 100 tonnes, e.g. at least 250 tonnes, e.g. of more than 500 tonnes, - a liquid fillable drop tank (110), that has a capacity to hold more than 500m3, e.g. more than 1000m3, of a liquid therein and that is vertically mobile relative to, e.g. above, the drive head member, - a lift system (20), preferably arranged between the drive head member (8) and the drop tank, that is configured to bring the drop tank (110) into an initial height position relative to the drive head member (8), - a quick release mechanism (25) adapted to effect quick release of the lift system (20) so that the drop tank falls down from said initial height position, - an energy transfer assembly (30) configured for transfer of energy from the falling drop tank to the drive head member (8), wherein, for driving the pile (1) into the soil, the drop tank (110) is at least partially filled with liquid, e.g. water, e.g. seawater, to set a desired total mass of the drop tank, wherein the pile driving system is operable in a repeated cycle wherein: - the liquid filled drop tank (110) is lifted by means of the lift system into a desired initial height position, - the quick release mechanism is operated to effect quick release of the lift system so that the liquid filled drop tank falls down from said initial height position towards the drive head member, and wherein energy from the falling liquid filled drop tank (110) is transferred by said energy transfer assembly to the drive head member and thereby to the pile, e.g. to the top end of the pile, so that the pile is driven deeper into the soil.
  3. Pile driving system according to claim 1 or 2, wherein said energy transfer assembly (30) comprises one or more spring devices (31) and/or one or more damper devices (31), that are effective between the drop weight assembly (10) or the drop tank (110) and the drive head member (8).
  4. Pile driving system according to claim 3, wherein said one or more spring devices (31) and/or one or more damper devices (31) are cooled, e.g. by cooling water, e.g. seawater, being circulated through or along external wall portions of the one or more spring devices (31) and/or one or more damper devices (31) and/or cooling water being sprayed on external wall portions of the one or more spring devices (31) and/or one or more damper devices (31).
  5. Pile driving system according to claim 4, wherein the energy transfer assembly (30) comprises multiple gas spring devices (31) each comprising a compressible gas filled variable volume chamber that is reduced in volume as the drop weight assembly (10) or drop tank (110) falls, and/or multiple liquid damper devices (31), each comprising a liquid filled variable volume chamber and an associated liquid flow resistance through which at least a part of said liquid is forced upon compression of the liquid filled variable volume chamber as the drop weight assembly (10) or drop tank (110) falls, e.g. the liquid of the multiple liquid damper devices (31) being circulated through a heat exchanger system so as to cool said liquid, e.g. wherein the energy transfer assembly (30) comprises multiple integrated spring and damper devices (31), wherein each integrated spring and damper device (31) comprises a compressible gas filled variable volume chamber that is reduced in volume as the drop weight assembly (10) or drop tank falls, and wherein each integrated spring and damper device (31) comprises a liquid filled variable volume chamber and an associated liquid flow resistance through which at least a part of said liquid is forced upon compression of the liquid filled variable volume chamber as the drop weight assembly (10) or drop tank (110) falls.
  6. Pile driving system according to claim 4 or 5, wherein the one or more spring devices (31) and/or the one or more damper devices (31), e.g. embodied as integrated spring and damper devices (31), are arranged on the drive head member (8), each engaging at a lower end thereof the drive head member (8), and/or wherein an array of multiple spring devices (31) and/or of multiple damper devices (31), e.g. embodied as multiple integrated spring and damper devices (31), is arranged underneath the support structure (11).
  7. Pile driving system according to claim 1, wherein the pile driving system (7) comprises a vertical guide structure (13) configured to vertically guide the drop weight assembly (10) relative to the drive head member (8), e.g. wherein multiple vertical pylons (14) are arranged on the drive head member, e.g. wherein the drop weight assembly (10) or the drive head member (8) is provided with vertical guide members (13), e.g. vertical pylons (13), wherein the drop weight is composed of stackable steel elements (12a, 12b, 12c, 12d, 12s), e.g. planar steel elements, that are stacked on the support structure (11) between the vertical guide members, e.g. vertical pylons (13) and/or wherein a lifting tool (6) is present that is configured to engage and retain stackable steel elements of the drop weight assembly.
  8. Pile driving system according to any one of claims 1-7, wherein the lift system (20) comprises multiple hydraulic lift cylinders (21), and wherein, preferably, the quick release mechanism (25) comprises one or more quick release valves that are opened to allow rapid discharge of hydraulic liquid from the lift cylinders (21), e.g. wherein the hydraulic liquid of the multiple lift cylinders (21) is circulated through a heat exchanger system so as to cool the hydraulic liquid, e.g. said heat exchanger system being fed with seawater for cooling the circulated hydraulic liquid in case the pile (1) is installed into the seabed.
  9. Use of a pile driving system according to any one of claims 1 - 8 for driving a pile, e.g. a hollow and open ended pile, e.g. a large diameter pile having an outer diameter of at least 5 meters, e.g. a monopile of an offshore wind turbine, into the soil, e.g. into the seabed.
  10. Method for installation of a monopile foundation of an offshore wind turbine wherein use is made of a pile driving system according to any one of claims 1 - 8.
  11. A marine vessel, e.g. a jack-up marine vessel, provided with a pile driving system according to any one of claims 1 - 8, e.g. the vessel comprising a pile holder adapted to hold the pile vertical during pile driving, e.g. the vessel comprising a crane.
  12. Pile driving method for driving a pile (1), e.g. a hollow and open ended pile, e.g. a large diameter pile having an outer diameter of at least 5 meters, e.g. a monopile of an offshore wind turbine, into the soil, e.g. into the seabed, wherein use is made of a pile driving system (7) according to claim 1 and optionally any one or more of claims 3-11, the method comprising a repeated cycle wherein: - the drop weight assembly (10) is lifted by means of the lift system (20) into a desired initial height position, - the quick release mechanism (25) is operated to effect quick release of the lift system (20) so that the drop weight assembly (10) falls down from said initial height position towards the drive head member (8), and wherein energy from the falling drop weight assembly (10) is transferred by said energy transfer assembly (30) to the drive head member (8) and thereby to the pile (1), e.g. to the top end of the pile (1), so that the pile (1) is driven deeper into the soil.
  13. Pile driving method for driving a pile (1), e.g. a hollow and open ended pile, e.g. a large diameter pile having an outer diameter of at least 5 meters, e.g. a monopile of an offshore wind turbine, into the soil, e.g. into the seabed, wherein use is made of a pile driving system (7) according to claim 2 and optionally any one or more of claims 3-11, the method comprising a repeated cycle wherein: - the liquid filled drop tank (110) is lifted by means of the lift system (20) into a desired initial height position, - the quick release mechanism (25) is operated to effect quick release of the lift system so that the liquid filled drop tank falls down from said initial height position towards the drive head member, and wherein energy from the falling liquid filled drop tank (10) transferred by said energy transfer assembly to the drive head member (8) and thereby to the pile (1), e.g. to the top end of the pile, so that the pile is driven deeper into the soil.
  14. Pile driving method according to claim 12 or 13, wherein said energy transfer is devoid of mechanical impact energy transfer between the drop weight assembly (10) and drive head (8) or between the drop tank (110) and drive head (8), e.g. wherein the energy transfer assembly (30) is devoid of an anvil.
  15. Pile driving method according to any one of claims 12-14, wherein the pile (1) has an open foot end and an outer diameter of at least 5 meter.

Description

The present invention relates to the field of pile driving. The present invention envisages as a particular embodiment the driving of large diameter open ended and hollow piles, e.g. having an outer diameter of at least 5 meters. Such large piles are nowadays, for example, employed as monopile foundations for offshore wind turbines. Practical embodiments nowadays envisaged include monopiles having a diameter between 5 and 12 meters, and lengths between 60 and 120 meters. US4817733 discloses a pile driving method wherein use is made of a pile driving system, which pile driving system comprises: a drive head member that is configured to be arranged on the top end of the pile,a drop weight that is vertically mobile above the drive head member,a lift system arranged between the drive head member and the drop weight, which lift system is configured to bring the drop weight into an initial height position relative to the drive head,a quick release system adapted to effect quick release of the lift system so that the drop weight falls down from said initial height position,an energy transfer assembly configured for transfer of energy from the falling drop weight to the drive head member. For driving the pile into the soil, the method comprising a repeated cycle wherein: the drop weight is lifted by means of the lift system into a desired initial height position,the quick release mechanism is operated to effect quick release of the lift system so that the drop weight falls down from said initial height position towards the drive head member, wherein energy from the falling drop weight is transferred by the energy transfer assembly to the drive head member and thereby to the top end of the pile, so that the pile is driven deeper into the soil. DE10340088 discloses a free-fall hammer for driving large piles employed as foundation for offshore wind turbines, which should have a required drop weight of about 800-900 tonnes. The present invention aims to provide measures that result in an improved or at least alternative pile driving method, e.g. in view of an envisaged application for driving of large diameter open ended and hollow piles, e.g. having an outer diameter of at least 5 meters, e.g. employed as monopile foundations for offshore wind turbines. The invention provides according to a first aspect thereof a pile driving system for driving a pile according to claim 1 and a pile driving method for driving a pile according to claim 12, wherein use is made of the pile driving system of claim 1. In this method according to a first aspect use is made of a pile driving system, which pile driving system comprises a drive head member that is configured to engage the pile, e.g. is configured to be arranged on the top end of the pile, e.g. the drive head member having a mass of at least 100 tonnes, e.g. at least 250 tonnes, e.g. of more than 500 tonnes. The pile driving system according to the first aspect further comprises a solid mass drop weight assembly comprising a support structure and comprising solid drop weight elements supported by said support structure, preferably solid steel drop weight elements being composed of steel elements, e.g. stackable steel elements, which drop weight elements have a total mass of more than 500 tonnes, e.g. more than 1000 tonnes, e.g. more than 2000 tonnes, e.g. up to 3000 tonnes, which drop weight assembly is vertically mobile relative to, e.g. above, the drive head member. It will be appreciated that the weight of the support structure also plays a role in the total mass that is dropped from the initial height. For example, the support structure has a mass of at least 100 tonnes, e.g. at least 250 tonnes, e.g. at least 500 tonnes. The weight of this structure is in practical embodiments predominantly governed by the required strength, e.g. in view of the capability to handle a drop weight elements composition weighing over 500, 1000, or even over 2000 tonnes, e.g. up to 3000 tonnes. In embodiments, the support structure is embodied to support thereon solid drop weight elements having mass in total of at least 500, e.g. at least 100, preferably at least 2000 tonnes. The enormous mass of the solid mass drop weight assembly allows to dispense with any mechanism that would provide additional acceleration of the drop weight assembly during the fall, so that the fall is solely under the influence of gravity, so at 1G. This not only allows for a much simpler design than the well-known accelerated hydraulic hammer, wherein the ram block of the hammer is accelerated by gas pressure acting on the piston type ram block to a blow rate corresponding to twice the rate of free drop. In the field, the largest mass of the accelerated ram block is about 200 tonnes. The invention envisages a total drop weight assembly mass that is multiple times larger than in the prior art, e.g. of at least 500 tonnes and preferably far greater. The enormous mass of the falling, non-accelerated drop weight assembly m