Multi-cavity grouting deviation rectifying device and method suitable for land wind power multi-pile foundation

Abstract

The invention provides a multi-cavity grouting deviation rectifying device and method suitable for an onshore wind power multi-pile foundation, and belongs to the technical field of onshore wind power. A first-stage chamber, a second-stage chamber and a third-stage chamber are sequentially arranged in the shell from bottom to top. The first-stage cavity, the second-stage cavity and the third-stage cavity are separated through flexible expandable diaphragms, grouting connectors are formed in the first-stage cavity, the second-stage cavity and the third-stage cavity, and the grouting connectors communicate with a ground grouting control system through grouting pipes. According to the invention, through the modularized independent grouting chamber preset at the bottom of the pile foundation, the real-time inclination monitoring system is combined, and the composite lifting force formed by layered high-pressure grouting is adopted, so that the gradient correction of the differential settlement of the foundation is realized, and finally, the inclination of the foundation is regulated and controlled within the limit value range required by specifications.

Description

Technical Field

[0001] This invention relates to the field of onshore wind power technology, and in particular to a multi-cavity grouting correction device and a correction method for the device, applicable to multi-pile foundations of onshore wind power. Background Art

[0002] During the long-term mining of coal resources, large areas of coal mining subsidence zones and areas with high backfill soil have generally formed. The foundation settlement in these areas is not yet stable, easily leading to uneven settlement of wind turbine foundations, which can cause tower tilting or foundation damage. Currently, there are no successful construction cases in these areas. As the development of onshore wind power resources continues to deepen, high-quality site resources are becoming increasingly scarce. Subsidence zones and backfill areas possess large usable land areas and good wind energy resources, showing potential for further development. However, their foundation settlement is difficult to predict and control. Therefore, it is urgent to research and develop suitable wind power foundation structure forms and settlement control and repair technologies for these special foundation conditions to ensure the feasibility and economy of wind power projects in complex sites such as subsidence zones, and to promote their engineering application.

[0003] To address the potential for uneven settlement and tilting of onshore wind turbine foundations, strict control is necessary. According to the "Design Code for Wind Turbine Foundations in Onshore Wind Farm Projects," the allowable tilt angle of the wind turbine foundation should be controlled within the range of 3‰ to 6‰ to ensure the verticality and operational stability of the tower structure. During the design and construction phases, a high-precision monitoring system should be used to monitor the settlement trend in real time. Simultaneously, settlement remediation measures should be pre-planned to achieve rapid correction and secondary leveling of localized settlement, thereby ensuring the safe and long-term stable operation of the wind turbine under complex geological conditions. Summary of the Invention

[0004] In view of this, in order to solve the technical problems of uniform settlement and tilting in onshore wind power, on the one hand, the present invention provides a multi-cavity grouting correction device suitable for multi-pile foundations of onshore wind power. By pre-setting modular independent grouting chambers at the base of the pile, combined with a real-time tilt monitoring system, the composite lifting force formed by layered high-pressure grouting is used to achieve gradient correction of the differential settlement of the foundation, and finally keep the foundation tilt within the limit required by the standard.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A multi-cavity grouting correction device suitable for multi-pile foundations of onshore wind power includes:

[0007] The outer shell has, from bottom to top, a primary chamber, a secondary chamber, and a tertiary chamber.

[0008] The primary, secondary, and tertiary chambers are separated by a flexible, expandable diaphragm. Each of the primary, secondary, and tertiary chambers is equipped with a grouting interface, which is connected to the ground grouting control system via a grouting pipe.

[0009] Preferably, the top of the three-stage chamber is provided with a rigid support block for contacting the pile base surface.

[0010] Preferably, the flexible expandable diaphragm is made of high-strength fiber, which ensures both the sealing between the chambers and provides expansion buffering capacity.

[0011] Preferably, one-way valves are provided at the grouting interfaces of the primary chamber, secondary chamber, and tertiary chamber.

[0012] Preferably, it further includes:

[0013] A support ring is disposed outside or between the primary, secondary, and tertiary chambers to maintain stability and shape control in the vertical expansion direction.

[0014] Preferably, it also includes a sealing ring to ensure that no leakage occurs during the grouting process.

[0015] Preferably, it also includes a groove for embedding the steel cage used as a pile foundation in the installation slot.

[0016] Preferably, the grouting pipe is made of high-pressure resistant and corrosion-resistant alloy steel.

[0017] Preferably, the outer casing is coated with an anti-corrosion coating.

[0018] On the other hand, the present invention provides a correction method for the above-mentioned multi-cavity grouting correction device applicable to multi-pile foundations of onshore wind power, comprising the following steps:

[0019] When the monitoring system detects uneven settlement or tilting of the pile foundation, the ground grouting pump station system is activated to inject cement-based grout into the primary chamber. Under the push of the flexible expandable diaphragm, the grouting deformation occurs, which lifts the bottom of the pile foundation and gradually levels it.

[0020] If settlement occurs again after the first-level chamber is leveled and multiple leveling operations are required, grouting is injected into the second-level and third-level chambers in sequence to achieve a larger lifting volume in stages and complete multiple corrections of tilted or settled pile foundations.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] (1) Graded independent leveling and precise control to achieve long-term dynamic correction.

[0023] Structural support: The device adopts a three-level independent chamber (level 1, level 2, and level 3) vertical layer design. Each chamber is isolated by a high-strength fiber partition and a one-way valve, and is equipped with an independent grouting pipe connected to the ground control system.

[0024] Method support: When correcting deviations, the first-level chamber (maximum initial lift) is activated first. If insufficient, the second-level (medium lift) and third-level (fine adjustment) chambers are activated in sequence. The differential settlement is accurately corrected by controlling the gradient grouting volume.

[0025] Advantages: Single-stage or multi-stage grouting can be flexibly selected according to the settlement amount, and multiple repeated leveling is supported (within the entire life cycle of the wind turbine), solving the problem that traditional repair methods (such as overall jacking) cannot be corrected a second time after a one-time adjustment.

[0026] (2) Minimally invasive construction design reduces project interference and costs.

[0027] Structural support: The device is positioned at the bottom of the pile foundation through a groove, and concrete is poured together with the steel cage to form an integral structure; the outer shell is coated with an anti-corrosion coating and a sealing ring to ensure durability in underground environments.

[0028] Method support: The grouting process is operated remotely by ground pump units, without the need for excavation or demolition of the foundation structure, and the grout is delivered only through pre-set grouting pipes.

[0029] Advantages: Compared with traditional "excavation and backfilling" or "foundation reinforcement", the construction period is shortened, interference with wind turbine operation is avoided, construction waste is reduced, and the overall cost is reduced.

[0030] (3) Collaborative leveling capability, adapting to complex multi-pile foundation scenarios

[0031] Structural support: Each pile foundation in a multi-pile cap can be independently equipped with a set of correction devices. Each device is rigidly connected to the pile foundation through rigid support blocks, supporting the synchronous or sequential activation of multiple devices.

[0032] Method support: Based on real-time monitoring data (such as inclinometer feedback), grouting is given priority to pile foundations with large settlement (such as piles A and B in a six-pile cap), and the overall leveling of the platform is achieved through coordinated control of grouting volume and rate.

[0033] Advantages: It can perform multi-point coordinated correction for areas with uneven settlement, avoid structural stress concentration caused by single-point lifting, and ensure the overall stability of the pier platform.

[0034] (4) Material and structural optimization to improve durability and adaptability

[0035] Structural support: A flexible, expandable diaphragm converts slurry pressure into vertical lifting force, preventing the slurry from directly contacting metal components;

[0036] The support ring constrains the lateral expansion of the chamber, ensuring the directional transmission of expansion force. High-pressure grouting pipes (made of alloy steel) and a grout stop valve prevent leakage.

[0037] Advantages: The device is adaptable to complex geological conditions of multi-pile foundations for onshore wind power (such as coal mining subsidence areas and high backfill soil), its design life is synchronized with the wind turbine foundation, and it is compatible with pile foundations of different diameters (through modular size adjustment).

[0038] (5) Environmentally friendly and operation and maintenance friendly, reducing energy consumption throughout the entire life cycle.

[0039] Method support: Fast-setting micro-expansion cement grout is used, which hardens rapidly after grouting to form a stable support, and the grouting channel is retained for maintenance in the later stage; there is no need to frequently replace structural components.

[0040] Advantages: The restoration process causes minimal disturbance to the surrounding ecological environment, reduces material consumption, and allows for remote monitoring and correction via a ground control system during the operation and maintenance phase, significantly reducing manual inspection costs. Attached Figure Description

[0041] Figure 1 A three-dimensional schematic diagram of the multi-cavity grouting correction device;

[0042] Figure 2 This is a schematic diagram of the overall plan of the multi-cavity grouting correction device;

[0043] Figure 3 This is a schematic diagram of the grouting technology construction process;

[0044] Figure 4 Initial plan view for multi-chamber grouting correction;

[0045] Figure 5 Plan view of leveling and adjusting the first-stage grouting chamber for multi-chamber grouting correction;

[0046] Figure 6 Plan view for leveling and correcting deviation in multi-chamber grouting and three-chamber grouting;

[0047] In the diagram, 1. Pile foundation; 2. Anti-corrosion coating; 3. Outer shell; 4. Grouting pipe; 5. Rigid support block; 6. Tertiary chamber; 7. Secondary chamber; 8. Primary chamber; 9. One-way valve; 10. Flexible expandable diaphragm; 11. Support ring; 12. Sealing ring; 13. Groove; A. First correction device; B. Second correction device; C. Third correction device; D. Fourth correction device; E. Fifth correction device; F. Sixth correction device. Detailed Implementation

[0048] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0049] In the description of this invention, it should be noted that the terms "upper", "lower", "inner", "outer", "top / bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0050] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "sleeved / connected," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0051] like Figure 4-6 As shown, the present invention provides a multi-cavity grouting correction device suitable for multi-pile foundations of onshore wind power, comprising:

[0052] The outer shell 3 contains, from bottom to top, a primary chamber 8, a secondary chamber 7, and a tertiary chamber 6. The outer shell 3 provides external rigid constraints for the multi-chamber grouting system, ensuring that internal stress can be transmitted upwards during grouting expansion and preventing grout leakage. It must possess good structural strength and sealing performance.

[0053] Primary chamber 8: The lowest chamber, in direct contact with the rigid outer shell 3, is the unit prioritized for grouting during the initial lifting. Injection of cement-based grout produces the maximum initial lifting effect.

[0054] Secondary chamber 7: An intermediate grouting chamber located between primary chamber 8 and tertiary chamber 6, providing a moderate degree of lifting effect. Typically, after grouting in primary chamber 8, an assessment is made to determine whether entry into secondary chamber 7 is necessary for displacement adjustments.

[0055] Third-level chamber 6: The uppermost grouting chamber, used to provide further leveling capability when the first two chambers cannot achieve sufficient lifting. It has a small expansion stroke and fine adjustment function.

[0056] The primary chamber 8, the secondary chamber 7, and the tertiary chamber 6 are separated by a flexible expandable diaphragm 10. Each of the primary chamber 8, the secondary chamber 7, and the tertiary chamber 6 is provided with a grouting interface, which is connected to the ground grouting control system through a grouting pipe 4.

[0057] The flexible, expandable diaphragm 10 is located above the interior of each chamber and can expand as the volume of the injected grout changes. It converts the pressure of the grout into an upward lifting force and maintains a sealed environment to prevent the grout from directly contacting the structure.

[0058] Grouting pipe 4 is a high-pressure delivery pipeline connecting the ground grouting pump station system to the grouting ports of each chamber. Each chamber is equipped with an independent grouting pipe 4 for easy staged grouting control and is equipped with a grout stop valve. The grouting pipe 4 is preferably made of high-pressure resistant and corrosion-resistant alloy steel.

[0059] In this invention, a rigid support block 5 is provided at the top of the third-level chamber 6 for contacting the bottom surface of the pile foundation 1. The rigid support block 5 contacts the bottom surface of the pile foundation 1, and the pile foundation 1 is lifted by the thrust generated by the expansion of the lower chamber (secondary chamber 7). The rigid support block 5 ensures that the force is uniform and stable during the lifting process.

[0060] In this invention, the flexible expandable diaphragm 10 is made of high-strength fiber, such as aramid fabric (Kevlar) composite rubber membrane, which not only ensures the sealing between each chamber, but also provides expansion buffering capacity.

[0061] In this invention, one-way valves 9 are provided at the grouting interfaces of the primary chamber 8, secondary chamber 7, and tertiary chamber 6. The one-way valves 9 ensure unidirectional flow of grout and prevent backflow, thus preventing grout return, cross-contamination, or contamination during the grouting process. Spring-loaded mechanical check valves or soft-seal valve structures can be used.

[0062] This invention also includes:

[0063] A support ring 11 is disposed around or between the primary chamber 8, the secondary chamber 7, and the tertiary chamber 6 to maintain stability and shape control in the vertical expansion direction. The support ring 11 provides structural rigidity to the cavity, preventing the flexible material from laterally expanding and deforming during grouting, and maintaining stability and shape control in the vertical expansion direction.

[0064] This invention also includes sealing rings 12 to ensure that no leakage occurs during the grouting process. The sealing rings 12 are located at each connection point and at the closed edges of each chamber to ensure that the entire device does not leak during the grouting process.

[0065] In this invention, a groove 13 is also included, which serves as an installation slot for the reinforcing cage of the pile foundation 1. The groove 13 is used to precisely position the assembly position of each component and serves as an installation slot for the reinforcing cage of the pile foundation 1.

[0066] In this invention, the grouting pipe 4 is made of high-pressure resistant and corrosion-resistant alloy steel.

[0067] In this invention, the outer casing 3 is coated with an anti-corrosion coating 2. The anti-corrosion coating 2 preferably covers the outer casing 3 and the surface of the metal components to improve corrosion resistance and extend service life in humid, underground, or corrosive environments.

[0068] by Figure 1-3 Taking the overall structure consisting of six pile foundations 1 and the pile cap platform as an example, each pile foundation is equipped with a correction device, such as... Figure 2 The system consists of a first correction device A, a second correction device B, a third correction device C, a fourth correction device D, a fifth correction device E, and a sixth correction device F.

[0069] The working principle of this invention is as follows:

[0070] The bottom integrates multiple independent grouting chambers, each equipped with an independent grouting interface, connected to the ground grouting control system via grouting pipe 4. Each chamber is isolated by a one-way valve 9, enabling graded independent grouting control. The grouting pipe 4 is made of high-pressure resistant and corrosion-resistant alloy steel and incorporates an internal grout-stopping device to prevent grout backflow and leakage. The grout-stopping device is a mechanical seal installed inside the grouting pipe 4 to prevent grout backflow or leakage during non-grouting operations; it works in conjunction with the one-way valve. The one-way valve controls the grout flow direction within the chambers, while the grout-stopping device primarily prevents grout backflow along the grouting pipe, protecting the grouting system. Common structural forms include spring-loaded sealing cores, expansion plugs, and conical check valve bodies.

[0071] A rigid support block 5 is provided at the top, which is in direct contact with the bottom of the pile foundation 1 to bear and transmit the expansion and lifting force, thereby achieving local or overall leveling of the pile foundation 1. The multi-layer grouting chamber structure is made of flexible polymer material and is stacked vertically in layers, with the bottom layer being the primary chamber 8, which is in direct contact with the rigid structure of the outer shell 3. High-strength fiber-reinforced partitions are provided between each chamber. These partitions ensure the sealing between the chambers and provide a certain expansion buffer capacity to prevent interference or deformation transmission between adjacent chambers during the grouting expansion process.

[0072] On the other hand, the present invention provides a correction method for the above-mentioned multi-cavity grouting correction device applicable to multi-pile foundations of onshore wind power, comprising the following steps:

[0073] When the monitoring system detects uneven settlement or tilting of pile foundation 1, the ground grouting pump station system is activated to inject cement-based grout (such as quick-setting micro-expansion cement grout) into the primary chamber 8. Under the push of the flexible expandable diaphragm 10, it produces bulging deformation, which lifts the bottom of pile foundation 1 and gradually levels it.

[0074] If settlement occurs again after the first-level chamber 8 has been leveled and multiple leveling operations are required, grouting will be performed sequentially into the second-level chamber 7 and the third-level chamber 6 to achieve a larger lifting volume in stages and complete multiple corrections to the tilted or settled pile foundation 1.

[0075] The above description is merely a preferred embodiment of the present invention. However, the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention should be covered within the scope of protection of the present invention.

Claims

1. A multi-cavity grouting correction device suitable for multi-pile foundations of onshore wind power, characterized in that, include: The outer shell has, from bottom to top, a primary chamber, a secondary chamber, and a tertiary chamber. The primary, secondary, and tertiary chambers are separated by a flexible, expandable diaphragm. Each of the primary, secondary, and tertiary chambers is equipped with a grouting interface, which is connected to the ground grouting control system via a grouting pipe.

2. The multi-cavity grouting correction device for multi-pile foundations of onshore wind power as described in claim 1, characterized in that, The top of the three-stage chamber is equipped with a rigid support block for contacting the pile base surface.

3. The multi-cavity grouting correction device for multi-pile foundations of onshore wind power as described in claim 1, characterized in that, The flexible expandable diaphragm is made of high-strength fiber, which ensures both the sealing between the chambers and provides expansion buffering capacity.

4. A multi-cavity grouting correction device for multi-pile foundations of onshore wind power as described in claim 1, characterized in that, One-way valves are installed at the grouting interfaces of the primary, secondary, and tertiary chambers.

5. A multi-cavity grouting correction device for multi-pile foundations of onshore wind power as described in claim 1, characterized in that, Also includes: A support ring is disposed outside or between the primary, secondary, and tertiary chambers to maintain stability and shape control in the vertical expansion direction.

6. A multi-cavity grouting correction device for multi-pile foundations of onshore wind power as described in claim 1, characterized in that, It also includes sealing rings to ensure that no leakage occurs during the grouting process.

7. A multi-cavity grouting correction device for multi-pile foundations of onshore wind power as described in claim 1, characterized in that, It also includes the groove for embedding the steel cage used as a pile foundation in the installation slot.

8. A multi-cavity grouting correction device for multi-pile foundations of onshore wind power as described in claim 1, characterized in that, The grouting pipe is made of high-pressure resistant and corrosion-resistant alloy steel.

9. A multi-cavity grouting correction device for multi-pile foundations of onshore wind power, as described in any one of claims 1-8, characterized in that, The outer shell is coated with an anti-corrosion coating.

10. A correction method for a multi-cavity grouting correction device suitable for multi-pile foundations of onshore wind power, as described in any one of claims 1-9, characterized in that... Includes the following steps: When the monitoring system detects uneven settlement or tilting of the pile foundation, the ground grouting pump station system is activated to inject cement-based grout into the primary chamber. Under the push of the flexible expandable diaphragm, the grouting deformation occurs, which lifts the bottom of the pile foundation and gradually levels it. If settlement occurs again after the first-level chamber is leveled and multiple leveling operations are required, grouting is injected into the second-level and third-level chambers in sequence to achieve a larger lifting volume in stages and complete multiple corrections of tilted or settled pile foundations.

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