CN112647533A

CN112647533A - Construction system and construction method for preventing slurry leakage in jacket foundation pile by pile-first method

Info

Publication number: CN112647533A
Application number: CN202011565530.2A
Authority: CN
Inventors: 高健岳; 王大鹏; 李鸿运; 王泉泉; 王金玉; 汪冬冬; 谷坤鹏; 刘思楠; 张君韬
Original assignee: CCCC Third Harbor Engineering Co Ltd; CCCC Shanghai Third Harbor Engineering Science and Technology Research Institute Co Ltd; CCCC Shanghai Harbour Engineering Design and Research Institute Co Ltd
Current assignee: CCCC Third Harbor Engineering Co Ltd; CCCC Shanghai Third Harbor Engineering Science and Technology Research Institute Co Ltd; CCCC Shanghai Harbour Engineering Design and Research Institute Co Ltd
Priority date: 2020-12-25
Filing date: 2020-12-25
Publication date: 2021-04-13

Abstract

The application discloses leak protection thick liquid construction system and construction method in stake method jacket foundation pile earlier, this construction system includes: the steel pipe pile and the jacket are inserted into the jacket, and an annular grouting space for grouting is formed between the steel pipe pile and the jacket; and a gravel filling layer is filled above the mud surface elevation inside the steel pipe pile. The construction method comprises the following steps: piling the steel pipe pile to a designed elevation; determining the filling amount of broken stones or melon seed sheets in the steel pipe pile; installing a jacket; leveling and locking the jacket; and pouring grouting material into the annular grouting space. The application aims at the foundation construction of the jacket by the pile-first method, particularly the jacket structure with the grouting connecting section above the mud surface elevation and the larger pile diameter, has the characteristics of simple construction method, low equipment requirement, saving on-sea construction time, reduction in grouting material loss rate, construction cost and the like, and provides powerful guarantee for ensuring the connection quality of the jacket and the steel pipe pile.

Description

Construction system and construction method for preventing slurry leakage in jacket foundation pile by pile-first method

Technical Field

The application belongs to the technical field of offshore wind power foundation construction, and particularly relates to a slurry leakage prevention construction system and a construction method in a jacket foundation pile by a pile-first method.

Background

According to the design and construction experience of offshore wind power projects at home and abroad, a jacket foundation structure is adopted for a fan foundation and an offshore booster station foundation of a deep sea wind power project with water of 20-50 meters. In 2015-2018, a large number of offshore booster station foundations such as Zhuhai Guishan offshore wind power demonstration projects and Guangdong Yangjiang offshore wind power projects in China start to adopt four-pile jacket foundations in batches, but the application water depth is generally less than 30 m. In 2019, a plurality of 30-50 m offshore wind power sites such as Guangdong-China-Canon Shanwei-Sha offshore wind power projects, Guangdong-China-Canon Shanghai offshore wind power projects, Guangdong-Huizhou offshore wind power projects, Fujian Changle offshore wind power projects and the like are largely in a three-pile or four-pile guide pipe frame foundation structure form, and the pile diameter is increased to 4-5m from 2-3m in the original design. In the finished and under-construction projects in China, the position relation between the grouting connecting section of the pile-method interpolation type jacket and the elevation of the mud surface is divided into two types, one type is that the grouting connecting section is partially above the mud surface and partially below the mud surface; the other is that the grouting connecting sections are all above the mud surface. For the first connection mode, before installing the jacket after the pile is driven, the jacket needs to be installed after mud is removed to the designed elevation in the pile. For the second connection mode, mud cleaning in the pile is not needed before the jacket is installed, and once slurry leakage occurs in the underwater grouting process, the risk of material waste, the risk of construction window waste and the risk of underwater grouting construction quality are greatly increased. Aiming at the condition of deeper water, the difficulty of underwater mud cleaning is very high, and the mud cleaning quality is difficult to ensure. At present, a design unit tends to adopt a second mode, namely, the elevation of the underwater grouting connecting section is improved to be higher than the elevation of a mud surface. Therefore, preventing and reducing slurry leakage become one of the key problems to be solved urgently.

The selected type of the first-pile-method internal-insertion type jacket foundation structure type packer is generally a passive rubber packer, and the phenomenon that a grouting packer fails in the actual engineering of offshore wind power jacket foundation construction sometimes occurs. The grouting plugging principle mainly achieves the plugging effect through the tight extrusion of the rubber packer and the inner wall of the steel pipe pile. Factors that affect packer damage leading to mud leakage are many, such as sea conditions, pile driving accuracy, jacket installation process and lowering speed.

Aiming at the foundation construction of a jacket by a pile-first method, in particular to the grouting connection construction of an annular grouting space between the jacket and a steel pipe pile, wherein the diameter of the steel pipe pile is 4-5m, and the grouting connection section is above the mud surface elevation, once the grout leaks, although the grouting connection quality can be ensured by prolonging the grouting time and excessive grouting, the grout leakage is far greater than the theoretical dosage, the actual dosage of grouting materials is several times of the theoretical dosage, and a large amount of material waste and construction window loss are caused. How to efficiently finish the site construction in a short window period becomes a key for reducing the construction cost of the foundation type.

Disclosure of Invention

The system and the method have the advantages that the construction method is simple, the equipment requirement is low, offshore construction time is saved, the loss rate of grouting materials and construction cost are reduced, and the like, and powerful guarantee is provided for ensuring the connection quality of a jacket and a steel pipe pile.

In order to solve the technical problem, the application is realized by the following technical scheme:

the application provides a leak protection thick liquid construction system in stake method jacket foundation pile earlier, includes: the steel pipe pile and the jacket are inserted into the jacket, and an annular grouting space for grouting is formed between the steel pipe pile and the jacket; and a gravel filling layer is filled above the mud surface elevation inside the steel pipe pile.

Further, in the anti-leakage construction system in the pile-first method jacket foundation pile, a packer is further arranged between the bottom of the annular grouting space and the gravel filling layer.

Further, in the anti-leakage construction system in the pile-first method jacket foundation pile, the packer is also communicated with a bottom sealing grouting pipeline.

Further, the leakage prevention construction system in the pile-first method jacket foundation pile is characterized in that the gravel filling layer comprises gravel and/or melon seed pieces.

Further, in the anti-leakage construction system for the pile-first method jacket foundation pile, the gravel filling layer further comprises sand for filling gaps.

Further, in the anti-leakage construction system in the pile-first method jacket foundation pile, at least one layer of prefabricated grouting pipeline is reserved on the jacket.

The application also provides a construction method of the anti-leakage construction system in the jacket foundation pile based on the pile-first method, which comprises the following steps:

piling the steel pipe pile to a designed elevation;

determining the filling amount of broken stones or melon seed sheets in the steel pipe pile;

installing a jacket;

leveling and locking the jacket;

and pouring grouting materials into an annular grouting space formed between the steel pipe pile and the jacket.

Further, the above construction method, wherein the piling of the steel pipe pile to a design level further comprises: determining the elevation of the mud surface in the steel pipe pile; and determining the filling height of the broken stone filling layer in the steel pipe pile.

Further, the construction method may further include, in the determining of the filling amount of the crushed stone or the melon seed sheet in the steel pipe pile,: and (3) hoisting prepared ton-packed broken stone or melon seed pieces in advance to the position near the pile top elevation of the steel pipe pile, filling the broken stone or melon seed pieces in the pile and leveling the broken stone or melon seed pieces by breaking bags underwater by a diver, and measuring the top elevation of the broken stone or melon seed pieces in the pile discontinuously in the filling process.

Further, the construction method may further include, in the determining of the filling amount of the crushed stone or the melon seed sheet in the steel pipe pile,: and after the broken stone filling layer is filled to the designed elevation, hoisting the ton-packed fine sand prepared in advance to the position near the pile top elevation of the steel pipe pile, performing underwater bag breaking by a diver to fill and level the sand in the pile, and measuring the elevation of the broken stone/melon seed sheet-sand top in the pile in the filling process.

Further, in the construction method, a multipoint retest mode is adopted in the process of measuring the top elevation.

Further, the above construction method, wherein the grouting material is poured into the annular grouting space formed between the steel pipe pile and the jacket, further comprises: and (3) pouring a bottom sealing grouting material into the packer through a bottom sealing grouting pipeline, and pouring the grouting material into the annular grouting space through a prefabricated grouting pipeline after the bottom sealing grouting material is solidified.

Compared with the prior art, the method has the following technical effects:

(1) the filling and leakage-preventing construction system and the construction method for the jacket foundation pile by the pile-first method are provided for solving the problems that grouting material loss is large, on-site grouting time is increased, construction period is long, construction cost is high and the like due to bottom sealing failure and the like in the construction of the jacket foundation by the pile-first method of the construction project, and greatly reduce comprehensive risks of underwater grouting and leakage.

(2) This application is through before the installation jacket, survey in the stake mud face top elevation in fact, carry out rubble/melon seed piece-sand packing in the stake, ensure that the jacket installation is accomplished the back, the jacket is inserted sharp leg lower part guide part and rubble/melon seed piece-sand extrusion back, rubble/melon seed piece-sand top elevation is located packer elevation below certain distance in the annular grout space, the thick liquid problem that leaks that produces because of the back cover inefficacy (if the packer damages) in the current work progress has been solved in this application, for guaranteeing jacket grout joint quality, reduce construction cost and provide the powerful guarantee.

(3) This application rubble, melon seed piece, sand all are ton package packing, and the on-the-spot filling in-process goes on through its loop wheel machine, and broken package construction dive cooperation under water, on-the-spot packing is convenient, and the efficiency of construction is higher, and follow-up jacket installation is accomplished back grouting construction efficiency and is controllable.

Drawings

Other features, objects and advantages of the present application will become more apparent upon reading of the following detailed description of non-limiting embodiments thereof, made with reference to the accompanying drawings in which:

FIG. 1: the application discloses a structural schematic diagram I of a slurry leakage prevention construction system in a jacket foundation pile by a pile-first method;

FIG. 2: the application discloses a structural schematic diagram II of a slurry leakage prevention construction system in a jacket foundation pile by a pile-first method;

FIG. 3: the structure schematic diagram of the sand and stone filling layer operation is shown in the application;

FIG. 4: the application is a schematic structural diagram before filling of a sand and stone filling layer;

FIG. 5: the structure schematic diagram of the sand and stone filling layer after filling is shown;

FIG. 6: the application provides a flow chart of a construction method for preventing slurry leakage in a jacket foundation pile by a pile-first method.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

As shown in fig. 1 to 5, in one embodiment of the present application, a grout leakage prevention construction system in a foundation pile of a pile-first jacket 20 includes: the steel pipe pile comprises a steel pipe pile 10 and a jacket 20, wherein the jacket 20 is inserted into the steel pipe pile 10, and an annular grouting space 30 for grouting is formed between the steel pipe pile 10 and the jacket 20; a gravel packing layer 50 is further filled above the level of the mud surface inside the steel pipe pile 10. In the embodiment, at least a gravel filling layer 50 is filled in the mud level in the steel pipe pile 10, so that the problem of slurry leakage caused by the fact that the annular grouting space 30 is damaged by back-cover grouting in the existing construction process is effectively solved, and a powerful guarantee is provided for guaranteeing the grouting connection quality of the jacket 20 and reducing the construction cost.

As shown in fig. 1 and 2, the present embodiment is applicable to the grouting connection section being partially above the sea bed surface and partially below the sea bed surface, and may also be applicable to the grouting connection section being above the sea bed surface.

In this embodiment, the crushed stone filling layer 50 includes crushed stones 51 and/or melon seed pieces, and preferably, when the crushed stones 51 and/or melon seed pieces are thrown into the steel pipe pile 10, the crushed stones 51 and/or melon seed pieces may be packaged in bags or the like, for example, in ton-package packages, so as to facilitate the throwing operation.

Wherein, in the embodiment, the top elevation of the gravel pack 50 is a certain distance below the elevation of the packer 40 described below.

Specifically, as shown in fig. 3, a grouting construction ship is positioned at a near point, ton-packed crushed stone M1 and/or melon seed pieces prepared in advance are hoisted to be near the elevation of the pile top by a crane M on the grouting construction ship, a diver breaks a bag underwater to fill and level the crushed stone 51 in the pile, and the elevation of the crushed stone 51 in the pile or the melon seed piece top is measured discontinuously in the filling process.

Further, as shown in fig. 4 and 5, the gravel packing layer 50 further includes sand 52 for filling gaps, and preferably, for the sake of throwing, the sand 52 is packed in advance in a bag or the like, for example, in a ton-pack.

Specifically, after the broken stone 51 and/or the melon seed pieces are filled to a designed elevation, a ton-packed fine sand crane M1 prepared in advance is placed to the position near the elevation of the pile top through a crane M on a grouting construction ship, a diver breaks a bag underwater to fill and level sand in the pile, and the elevation of the broken stone/the melon seed pieces-sand top in the pile is measured in the filling process.

In this embodiment, the sand 52 is filled in the gaps between the broken stones 51 and/or the melon seed pieces, so that the filling density and strength of the sand-filled layer can be increased, and the safety guarantee can be provided for the grouting operation of the annular grouting space 30.

Further, a packer 40 is further arranged between the bottom of the annular grouting space 30 and the gravel packing layer 50, and bottom sealing operation of the annular grouting space 30 can be realized by filling bottom sealing grouting materials into the packer 40, so that foundation guarantee is provided for subsequent grouting connection in the annular grouting space 30.

Further, in this embodiment, the packer 40 is further communicated with a back cover grouting line, and back cover grouting can be performed on the packer 40 through the back cover grouting line.

At least one layer of prefabricated grouting pipeline 31 is reserved on the jacket 20, and grouting material is poured into the annular grouting space 30 through the grouting pipeline.

The prefabricated grouting pipeline 31 comprises a main grouting pipeline and at least one spare grouting pipeline, wherein the design height of the main grouting pipeline is 0.5-1m higher than the elevation of the bottom sealing grouting pipeline; similarly, the design elevation of the main grouting pipeline is 0.5-1m lower than the elevation of the standby grouting pipeline arranged adjacent to the main grouting pipeline; the difference of the design elevation of the standby grouting pipelines adjacently arranged is 0.5-1 m.

Further, an overflow port (not shown) may be further disposed at the top of the annular grouting space 30, and whether grouting is finished or not may be determined by observing the grout outlet condition of the overflow port.

In another embodiment of the present application, as shown in fig. 6, a method for preventing grout leakage in a pile-first jacket foundation pile comprises the steps of:

piling the steel pipe pile 10 to a designed elevation;

secondly, determining the filling amount of the broken stones 51 or the melon seed sheets in the steel pipe pile 10;

step three, installing the jacket 20;

step four, leveling and locking the jacket 20;

and fifthly, pouring grouting materials into the annular grouting space 30 formed between the steel pipe pile 10 and the jacket 20.

In the first step, the method of piling the steel pipe pile 10 to the design standard further includes: determining the elevation of the mud surface in the steel pipe pile 10; and determining the filling height of the gravel filling layer 50 in the steel pipe pile 10.

Specifically, after the steel pipe pile 10 is driven to the designed elevation, the elevation of the mud surface in the pile is measured. After the steel pipe pile 10 is driven to the design elevation, mud surface elevation in the pile is measured through divers, the mud surface elevation in the pile is determined, and the filling height of the gravel filling layer 50 in the pile is determined according to the length and the void volume of the inserted pointed leg of the jacket 20.

Wherein, the elevation measurement of the mud surface in the pile is operated by a diver underwater, and is determined by multi-point measurement.

It should be noted that, the above-mentioned determination of the filling height of the gravel packing layer 50 in the steel pipe pile 10 takes into consideration the factors of the extrusion floating caused by insufficient bearing capacity of the sludge covering layer on the inner surface layer of the pile.

In the step two, determining the filling amount of the crushed stones 51 or the melon seed pieces in the steel pipe pile 10, the method further includes: and (3) hoisting the ton-packed broken stone M1 or the melon seed pieces prepared in advance to the position near the pile top elevation of the steel pipe pile 10, filling and leveling the broken stone 51 in the pile by breaking bags by divers underwater, and measuring the top elevation of the broken stone 51 in the pile discontinuously in the filling process.

When precise point positioning is required for near point positioning of the grouting construction ship, distances among a plurality of leg columns of the jacket 20 (three or four piles) are fully considered, and the number of ship moving times is reduced by combining with the crane M, so that the construction effect is provided.

Preferably, the ton-packed broken stone M1 prepared in advance is hoisted to be close to the elevation of the pile top by a crane M on a grouting construction ship, the convenience and the safety of underwater construction of a diver are fully considered, the ton-packed broken stone M1 is placed into the pile and stabilized, then the diver breaks a bag underwater, the diver is in a safe position after the bag is broken, the ton-packed broken stone M1 falls into the pile by the dead weight, and finally the diver levels.

In the filling process, the top elevation of the broken stone 51 in the pile is measured discontinuously, and the requirements of incapability of superfilling and different less filling are met so as to meet the construction requirements.

In the step two, determining the filling amount of the crushed stones 51 or the melon seed pieces in the steel pipe pile 10, the method further includes: and after the gravel filling layer 50 is filled to a designed elevation, hoisting the ton-packed fine sand M1 prepared in advance to be close to the pile top elevation of the steel pipe pile 10, filling and leveling sand in the pile by underwater bag breaking by a diver, and measuring the elevation of the gravel/melon seed slices-sand top in the pile in the filling process.

The method comprises the following steps of measuring the elevation of the top of broken stone/melon seed slices-sand in the pile again, and specifically, measuring the elevation of the top of broken stone/melon seed slices-sand in the pile 51-sand by adopting a multipoint repeated measurement mode after the broken stone/melon seed slices-sand in the pile is filled to the designed elevation.

Wherein in this embodiment said gravel 51-sand top elevation is preferably located at a distance below the level of the packer 40 described below.

In the step three of mounting the jacket 20, the method further includes: after the gravel filling layer 50 is filled, the jacket 20 is hoisted and installed, and the jacket is installed at the time of good sea condition and low wind power, so that the jacket is installed in place at one time.

In the leveling and locking of the jacket 20 in the above-mentioned step four, after the jacket 20 is installed, the levelness of the flange at the top of the jacket 20 is tested, and the levelness is adjusted by construction measures, so that after the design requirements are met, the temporary locking between the jacket 20 and the steel pipe pile 10 is completed by welding the jacket 20 and the steel pipe pile 10 underwater and the like.

In the step five, grouting material is poured into the annular grouting space 30 formed between the steel pipe pile 10 and the jacket 20, and the method further includes: and (3) pouring bottom sealing grouting material into the packer 40 through a bottom sealing grouting pipeline, and after the bottom sealing grouting material is solidified, pouring grouting material into the annular grouting space 30 through the prefabricated grouting pipeline 31.

In the description of the present application, unless expressly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, e.g., as meaning permanently connected, removably connected, or integral to one another; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

In this application, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may comprise direct contact of the first and second features, or may comprise contact of the first and second features not directly but through another feature in between. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

In the description of the present embodiment, the terms "upper", "lower", "left", "right", and the like are used based on the orientations and positional relationships shown in the drawings only for convenience of description and simplification of operation, and do not indicate or imply that the referred device or element must have a specific orientation, be configured and operated in a specific orientation, and thus, should not be construed as limiting the present application. Furthermore, the terms "first" and "second" are used only for descriptive purposes and are not intended to have a special meaning.

The above embodiments are merely to illustrate the technical solutions of the present application and are not limitative, and the present application is described in detail with reference to preferred embodiments. It will be understood by those skilled in the art that various modifications and equivalent arrangements may be made in the present invention without departing from the spirit and scope of the present invention and shall be covered by the appended claims.

Claims

1. The utility model provides an leak protection thick liquid construction system in stake method jacket foundation pile earlier which characterized in that includes: the steel pipe pile and the jacket are inserted into the jacket, and an annular grouting space for grouting is formed between the steel pipe pile and the jacket; and a gravel filling layer is filled above the mud surface elevation inside the steel pipe pile.

2. The system of claim 1, wherein a packer is disposed between the bottom of the annular grouting space and the gravel pack.

3. The system of claim 2, wherein the packer is further in communication with a back-cover grouting line.

4. The system of claim 1, wherein the gravel pack comprises crushed stone and/or melon seed pieces.

5. The system of claim 4, wherein the gravel pack further comprises sand for filling the gap.

6. The system for preventing slip casting in a pile-first method jacket foundation pile according to any one of claims 1 to 5, wherein at least one layer of prefabricated grouting line is reserved on the jacket.

7. A construction method based on the grout leakage prevention construction system in the pile-first method jacket foundation pile according to any one of claims 1 to 6, characterized by comprising the following steps:

piling the steel pipe pile to a designed elevation;

installing a jacket;

leveling and locking the jacket;

8. The construction method according to claim 7, further comprising driving the steel pipe pile to a design elevation: determining the elevation of the mud surface in the steel pipe pile; and determining the filling height of the broken stone filling layer in the steel pipe pile.

9. The construction method according to claim 7, wherein the determining of the filling amount of the crushed stone or the melon seed sheet in the steel pipe pile further comprises: and (3) hoisting prepared ton-packed broken stone or melon seed pieces in advance to the position near the pile top elevation of the steel pipe pile, filling the broken stone or melon seed pieces in the pile and leveling the broken stone or melon seed pieces by breaking bags underwater by a diver, and measuring the top elevation of the broken stone or melon seed pieces in the pile discontinuously in the filling process.

10. The construction method according to claim 9, wherein the determining of the filling amount of the crushed stone or the melon seed sheet in the steel pipe pile further comprises: and after the broken stone filling layer is filled to the designed elevation, hoisting the ton-packed fine sand prepared in advance to the position near the pile top elevation of the steel pipe pile, performing underwater bag breaking by a diver to fill and level the sand in the pile, and measuring the elevation of the broken stone/melon seed sheet-sand top in the pile in the filling process.

11. The construction method according to claim 9 or 10, wherein a multipoint retest mode is adopted in the process of measuring the top elevation.

12. The construction method according to any one of claims 7 to 10, wherein the grouting material is poured into the annular grouting space formed between the steel pipe pile and the jacket, and further comprises: and (3) pouring a bottom sealing grouting material into the packer through a bottom sealing grouting pipeline, and pouring the grouting material into the annular grouting space through a prefabricated grouting pipeline after the bottom sealing grouting material is solidified.