Cofferdam-free assembly type revetment reinforcement structure and construction method thereof

Abstract

The application discloses a cofferdam-free assembled type revetment reinforcing structure and a construction method thereof, and belongs to the technical field of revetment engineering reinforcement. The structure comprises a prefabricated sheet pile, a compacted grouting reinforcing body and a force transmission belt. The top of the prefabricated sheet pile is located below the design water level. The compacted grouting reinforcing body is filled between the prefabricated sheet pile and a revetment bottom plate. The force transmission belt is cast on the upper part of the grouting reinforcing body and is used for connecting the prefabricated sheet pile and the revetment bottom plate. During construction, a static pressure pile sinking machine is used to perform static pressure pile sinking construction on the prefabricated sheet pile. When the pile is sunk to the water surface, underwater static pressure pile delivery is continued to complete underwater pile sinking operation. Compacted grouting is performed. After the compacted grouting reinforcing body reaches a certain strength, part of the reinforcing body is removed and the force transmission belt is cast underwater. The compacted grouting reinforcing body and the force transmission belt are used to realize reliable cooperative stress of new and old structures under the condition of no cofferdam, and the application has the advantages of quick construction, basically no influence on navigation and direct reinforcing effect.

Description

Technical Field

[0001] This invention relates to the field of bank protection engineering reinforcement technology, specifically to a prefabricated bank protection reinforcement structure without cofferdam and its construction method. Background Technology

[0002] Bank protection structures are crucial facilities for ensuring the stability of river and waterway banks and preventing soil erosion and water flow. With the development of shipping and the improvement of flood control standards, many existing bank protection structures are experiencing problems such as insufficient load-bearing capacity and foundation erosion due to increased water depth, increased load, or material aging, necessitating reinforcement and renovation. Traditional reinforcement methods often suffer from drawbacks such as long construction periods, high costs, obstruction of waterway navigation, and high requirements for the back site.

[0003] Currently, there are various bank protection reinforcement solutions in the prior art that overcome the above-mentioned shortcomings. For example, Chinese invention patent application CN120906093A (publication date: November 7, 2025) discloses a combined bank protection for waterway reinforcement and its construction method, including load-bearing piles and sheet piles. The load-bearing piles are inserted along the edge of the waterway, and a sheet pile is inserted between two adjacent load-bearing piles. Each load-bearing pile is connected to at least one anchor rod for its installation and fixation. The load-bearing piles are provided with anchor holes for the corresponding anchor rod installation. The anchor holes have a contracting structure from the water-facing side of the load-bearing pile to the water-repellent side of the load-bearing pile, and form an installation guide and limit for the anchor rod. Both sides where the load-bearing piles and sheet piles are connected are provided with stop parts to restrict the movement of the sheet piles towards their water-facing side. The beneficial effects of this invention are: it integrates the combined revetment with the navigation shore, optimizes structural stress conditions, strengthens the revetment function, facilitates rapid channel reinforcement, and is cost-effective, minimizing the adverse impact of the reinforcement structure on navigation width; the anchor hole structure allows for underwater construction without the need for cofferdams, minimizing navigation obstruction and effectively improving construction efficiency and safety. While this scheme adapts to underwater construction guidance through its special anchor hole design, the stability of its reinforcement system highly depends on driving and tensioning a large number of anchor bolts into the soil behind the shore. This results in complex construction procedures, specific requirements for the working space and geological conditions behind the shore, and the overall structure is biased towards rigid protection; direct and efficient synergistic stress connection between the old and new structures is not its core design principle.

[0004] For example, Chinese invention patent application CN120745068A (publication date: October 3, 2025) discloses a design method and structure for active unloading sheet pile revetment reinforcement. This method involves adding reinforcement piles behind the revetment, utilizing the soil arch effect to coordinate the load with the front row of sheet piles. While this method is economical, its reinforcement effect heavily relies on precise pile spacing and specific soil conditions to form an effective soil arch. The design theory is complex, and the accuracy of pile placement during on-site construction is extremely high. Furthermore, this scheme fails to establish a direct, rigid mechanical connection between the old and new structures.

[0005] For example, Chinese invention patent application CN120906082A (publication date: November 7, 2025) discloses an ecological reinforcement structure for riverbank masonry retaining walls, which uses a double-row pile foundation (steel sheet piles and imitation wood piles) combined with a planting platform to construct ecological space while reinforcing the retaining wall base. However, its reinforcement mechanism mainly focuses on the anti-sliding of the base and the construction of ecological space. The newly built guide beam and pile foundation are completely below the normal water level. For common sheet pile or gravity revetments that need to resist huge horizontal earth pressure and whose reinforcement interface is located near the design water level, this scheme has obvious deficiencies in the effective transfer and distribution of horizontal loads, and its connection structure cannot ensure that the new and old structures work together as a whole.

[0006] In summary, existing revetment reinforcement technologies have certain limitations in terms of ease of construction and reliability of structural synergy. Therefore, there is an urgent need for a prefabricated reinforcement structure that is quick to construct, does not obstruct navigation, and can form a reliable and direct force-transfer structure with existing revetments, suitable for revetment reinforcement projects such as waterway upgrades in confined spaces, busy waterways, and projects with tight schedules. Summary of the Invention

[0007] To solve the above technical problems, the present invention provides a cofferdam-free prefabricated revetment reinforcement structure, which is installed on the water-facing side of an existing revetment and includes: the existing revetment; Precast sheet piles are installed on the water-facing side of the existing revetment and arranged along the extension direction of the existing revetment, with the top of the piles lower than the design navigation water level; The compacted grouting solidified body is filled between the precast sheet pile and the existing revetment, so that the precast sheet pile and the existing revetment can work together to bear the force; The force transmission strip, a concrete structure cast underwater, is installed on the upper part of the compacted grouting reinforced body and is used to transmit horizontal and vertical forces between the precast sheet piles and the existing revetment.

[0008] Furthermore, the precast sheet piles are interconnected by U-shaped interlocking joints with interlocking grooves.

[0009] Furthermore, the precast sheet pile is one of precast concrete sheet pile, steel sheet pile, or steel pipe pile with interlocking.

[0010] Furthermore, warning posts are also included, which are spaced between the existing revetment and the precast sheet piles.

[0011] Furthermore, the warning post is either a precast concrete post or a steel pipe post.

[0012] Furthermore, the force transmission strip is located between the precast sheet pile and the existing revetment bottom slab, and its thickness is the same as that of the existing revetment bottom slab.

[0013] This application also provides a construction method for building a prefabricated revetment reinforcement structure without a cofferdam, including the following steps: S1: On the water-facing side of the existing revetment, a static pressure pile driving machine is used to carry out static pressure pile driving construction on the precast sheet piles. When the piles reach the water surface, the underwater pile driving operation is continued by connecting an underwater static pressure pile driver. S2: Compacting grouting is performed in the underwater space between the precast sheet pile and the existing revetment bottom slab to form the compacted grouting reinforced body; S3: After the strength of the compacted grouting body reaches more than 50% of the design strength, remove part of the compacted grouting body located within the height range of the existing revetment bottom plate underwater; S4: Install warning posts, and in the cleared space, place the steel cage required for the force transmission belt, and pour micro-expansion underwater non-dispersible concrete to form the force transmission belt connecting the precast sheet piles and the existing revetment bottom slab.

[0014] Furthermore, in step S1, the static pressure pile driver is installed on a self-balancing lifting vessel on water, and no cofferdam is set up during the entire pile driving process.

[0015] Furthermore, after the micro-expansion underwater non-dispersive concrete poured in step S4 reaches its strength, the channel is dredged underwater to the design mudline.

[0016] Compared with existing technologies, the advantages and effects of this application are as follows: 1. Traditional cofferdams are difficult, costly, and risky to construct in areas with deep water, rapid currents, soft geology, or busy waterways. This application uses a self-balancing lifting vessel to carry a static pressure pile driver for pile driving, and an underwater static pressure pile driver to complete the underwater operation. The entire process does not require the construction of a cofferdam, avoiding the blockage and interference to the waterway caused by traditional reinforcement methods, significantly reducing the impact of construction on navigation, and eliminating the need to demolish the original revetment superstructure, allowing for direct reinforcement and greatly saving construction time.

[0017] 2. The core components of this application are formed by precast sheet piles (concrete sheet piles, steel sheet piles or steel pipe piles with interlocking joints) to form a continuous wall; the combination of compaction grouting and underwater force transmission strip casting process improves the integrity and load-bearing capacity of the structure, the assembly construction significantly shortens the construction period, and the factory production of precast components is conducive to quality control.

[0018] 3. This application connects the old and new structures together to share the load, resulting in excellent reinforcement and strong adaptability: The gap between the sheet piles and the existing revetment is filled by compaction grouting, and horizontal and vertical loads are effectively transferred by underwater-cast load transfer strips, forming a unified structure. This structure is suitable for different geological conditions and water level changes, and navigation safety can be enhanced by setting warning posts. The overall reinforcement method is economical, durable, and environmentally friendly.

[0019] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the preferred embodiments of this application are described in detail below with reference to the accompanying drawings.

[0020] The above and other objects, advantages and features of this application will become more apparent to those skilled in the art from the following detailed description of specific embodiments in conjunction with the accompanying drawings. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. In all drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0022] in: Figure 1 This is a schematic diagram of an assembled revetment reinforcement structure without a cofferdam. Figure 2 A top view of a prefabricated revetment reinforcement structure without a cofferdam; Figure 3 A schematic diagram of the construction method for a prefabricated revetment reinforcement structure without cofferdam; Figure 4 This is a schematic diagram of the construction location of a self-balancing lifting vessel on water.

[0023] Explanation of reference numerals in the attached drawings: 1-Precast sheet pile; 2-Gravity retaining wall base slab; 3-Gravity retaining wall; 4-Flood control dike; 5-Building; 6-Original mudline of the waterway; 7-Design mudline; 8-Force transmission belt; 9-Compacted grouting reinforced body; 10-Design navigation water level; 11-Warning post; 12-Self-balancing lifting vessel on water; 13-Static pressure pile driver; 14-Underwater static pressure pile driver. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. In the following description, specific details such as specific configurations and components are provided merely to help fully understand the embodiments of this application. Therefore, those skilled in the art should understand that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of this application. In addition, for clarity and brevity, descriptions of known functions and structures are omitted in the embodiments.

[0025] It should be understood that the phrase "an embodiment" or "this embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of this application. Therefore, "an embodiment" or "this embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments.

[0026] Furthermore, reference numerals and / or letters may be repeated in different examples within this application. Such repetition is for the purpose of simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or settings discussed.

[0027] In this article, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A exists alone, B exists alone, and A and B exist simultaneously. The term " / and" describes another type of relationship between related objects, indicating that two relationships can exist. For example, A / and B can mean: A exists alone, and A and B exist alone. In addition, the character " / " in this article generally indicates that the related objects before and after it have an "or" relationship.

[0028] In this article, the term "at least one" is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, "at least one of A and B" can mean: A exists alone, A and B exist simultaneously, or B exists alone.

[0029] It should also be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion.

[0030] Example 1 This embodiment introduces a prefabricated revetment reinforcement structure without a cofferdam. Please refer to the appendix. Figure 1 , Figure 1 This is a schematic diagram of an assembled revetment reinforcement structure without a cofferdam. The structure includes: There are currently 3 riverbank protection structures; Precast sheet piles 1 are installed on the water-facing side of the existing revetment 3 and arranged along the extension direction of the existing revetment 3; The compacted grouting reinforcement 9 is filled between the precast sheet pile 1 and the existing revetment 3, so that the precast sheet pile 1 and the existing revetment 3 can work together to bear the force; The force transmission band 8 is an underwater cast concrete structure, located on the upper part of the compacted grouting reinforced body 9, and is used to transmit horizontal and vertical forces between the precast sheet pile 1 and the existing revetment 3.

[0031] Furthermore, to avoid the precast sheet pile structure being exposed above the water surface, which would affect the cross-sectional area of ​​the waterway and the risk of ship collisions, the top of the precast sheet pile is set below the design navigable water level by 10 meters.

[0032] Furthermore, to reduce the risk of ships colliding with the revetment, 150mm@30m warning posts 11 are installed between the existing revetment 2 and the newly built precast sheet piles 1.

[0033] Furthermore, to reduce the wave height of ship waves, the newly constructed precast sheet pile 1 adopts a U-shaped sheet pile with interlocking concave and convex shapes.

[0034] Furthermore, the land side of the revetment is occupied by buildings 5 ​​or flood control dikes 4 and other structures, making it impossible to carry out onshore construction and arrange reinforcement structures onshore. Therefore, the revetment reinforcement structures are set on the water side.

[0035] Technical effects of this embodiment: This embodiment introduces a cofferdam-free prefabricated revetment reinforcement structure. This reinforcement structure is set in the water area on the water-facing side of the existing revetment, without the need for construction or cofferdam on the land side. It solves the problem of being unable to reinforce from the land side due to the limitations of buildings and other structures, and minimizes the impact on normal navigation and shore activities.

[0036] Example 2 Based on Example 1, this example discloses a further design of a prefabricated revetment reinforcement structure without a cofferdam. Please refer to [link to example]. Figure 2 , Figure 2 A top view of a prefabricated revetment reinforcement structure without a cofferdam; The precast sheet piles 1 are interconnected by U-shaped interlocking joints with interlocking grooves.

[0037] Furthermore, the precast sheet pile 1 is one of precast concrete sheet pile, steel sheet pile, or steel pipe pile with interlocking.

[0038] The revetment reinforcement structure also includes warning piles 11, which are spaced between the existing revetment 3 and the precast sheet piles 1.

[0039] Furthermore, the warning post 11 is either a precast concrete post or a steel pipe post.

[0040] Furthermore, the force transmission belt 8 is located between the precast sheet pile 1 and the existing revetment bottom plate 2, and its thickness is the same as that of the existing revetment bottom plate 2.

[0041] Furthermore, the interval h between the precast sheet pile 1 and the existing revetment bottom slab 2 is ≥200mm.

[0042] The technical effect of this embodiment: This embodiment connects the newly built precast sheet piles with the existing revetment as a whole by filling the underwater space with a compacted grouting body and casting a force transmission strip on the compacted grouting body. This achieves efficient transmission of horizontal and vertical forces and improves the overall stability of the reinforced revetment.

[0043] Example 3 Based on Examples 1 and 2, this example introduces a construction method for building a prefabricated revetment reinforcement structure without a cofferdam. Please refer to the appendix. Figure 3-4 , Figure 3 A schematic diagram of the construction method for a prefabricated revetment reinforcement structure without cofferdam; Figure 4 A schematic diagram of the construction location of a self-balancing lifting vessel on water. The construction method includes the following steps: S1: On the water-facing side of the existing revetment 3, a static pressure pile driving machine 13 is used to carry out static pressure pile driving construction on the precast sheet pile 1. When the pile reaches the water surface, the underwater static pressure pile driver 14 is connected to continue the underwater pile driving operation. S2: Compacting grouting is performed in the underwater space between the precast sheet pile 1 and the existing revetment bottom slab 2 to form the compacted grouting reinforced body 9; S3: After the strength of the compacted grouting body 9 reaches more than 50% of the design strength, remove part of the compacted grouting body located within the height range of the existing revetment bottom plate 2 underwater; S4: Install warning posts 11, and place the steel cage required for the force transmission belt 8 in the cleared space, and pour micro-expansion underwater non-dispersible concrete to form the force transmission belt 8 connecting the precast sheet pile 1 and the existing revetment bottom slab 2.

[0044] Furthermore, in step S1, the static pressure pile driver 13 is installed on the self-balancing lifting vessel 12 on the water, and no cofferdam is set up during the entire pile driving process.

[0045] Furthermore, after the micro-expansion underwater non-dispersive concrete poured in step S4 reaches its strength, the original mudline 6 of the waterway is dredged underwater to the designed mudline 7.

[0046] Technical advantages of this embodiment: This embodiment provides a construction method for building a prefabricated revetment reinforcement structure without cofferdam. The main components are manufactured in factories, and the construction mainly uses static pressure, grouting, and underwater casting processes. The quality is controllable and the construction period is relatively short.

[0047] The above description is merely a preferred embodiment of the present invention and does not limit the scope of protection of the present invention. Various modifications and variations are possible with respect to the present invention. Any changes, modifications, substitutions, integrations, and parameter alterations to these embodiments within the spirit and principles of the present invention fall within the scope of protection of the claims of the present invention.

Claims

1. A prefabricated revetment reinforcement structure without cofferdam, characterized in that, include: Existing bank protection (3); Precast sheet piles (1) are installed on the water-facing side of the existing revetment (3) and arranged along the extension direction of the existing revetment (3), with the top of the piles lower than the design navigation water level (10). The compacted grouting reinforcement (9) is filled between the precast sheet pile (1) and the existing revetment (3) so that the precast sheet pile (1) and the existing revetment (3) can work together to bear the force; The force transmission strip (8) is an underwater cast concrete structure, set on the upper part of the compacted grouting reinforced body (9), and is used to transmit horizontal and vertical forces between the precast sheet pile (1) and the existing revetment (3).

2. The prefabricated revetment reinforcement structure without cofferdam as described in claim 1, characterized in that, The precast sheet piles (1) are connected to each other by U-shaped interlocking joints with concave and convex spacing.

3. The prefabricated revetment reinforcement structure without cofferdam as described in claim 1 or 2, characterized in that, The precast sheet pile (1) is one of the following: precast concrete sheet pile, steel sheet pile or steel pipe pile with interlocking.

4. The prefabricated revetment reinforcement structure without cofferdam as described in claim 1, characterized in that, It also includes warning posts (11), which are spaced between the existing revetment (3) and the precast sheet piles (1).

5. The prefabricated revetment reinforcement structure without cofferdam as described in claim 4, characterized in that, The warning post (11) is either a precast concrete pile or a steel pipe pile.

6. The prefabricated revetment reinforcement structure without cofferdam as described in claim 1, characterized in that, The force transmission strip (8) is located between the precast sheet pile (1) and the existing revetment bottom plate (2), and its thickness is the same as that of the existing revetment bottom plate (2).

7. A construction method for constructing a prefabricated revetment reinforcement structure without cofferdam as described in any one of claims 1-6, characterized in that, Includes the following steps: S1: On the water-facing side of the existing revetment (3), a static pressure pile driving machine (13) is used to carry out static pressure pile driving construction on the precast sheet piles (1). When the pile reaches the water surface, the underwater pile driving operation is continued by connecting an underwater static pressure pile driver (14). S2: Compacting grouting is performed in the underwater space between the precast sheet pile (1) and the existing revetment bottom plate (2) to form the compacted grouting reinforced body (9). S3: After the strength of the compacted grouting reinforcement (9) reaches more than 50% of the design strength, remove part of the compacted grouting reinforcement located within the height range of the existing revetment bottom plate (2) underwater; S4: In the cleared space, place the steel cage required for the force transmission belt (8) and pour micro-expansion underwater non-dispersive concrete to form the force transmission belt (8) connecting the precast sheet pile (1) and the existing revetment bottom plate (2).

8. The construction method of the prefabricated revetment reinforcement structure without cofferdam as described in claim 7, characterized in that, In step S1, the static pressure pile driver (13) is installed on a self-balancing lifting vessel (12) on the water, and no cofferdam is set up during the entire pile driving process.

9. The construction method of the prefabricated revetment reinforcement structure without cofferdam according to claim 7, characterized in that, After step S3 is completed, warning posts (11) are installed simultaneously.

10. The construction method of the prefabricated revetment reinforcement structure without cofferdam according to claim 7, characterized in that, After the micro-expansion underwater non-dispersed concrete poured in step S4 reaches its strength, the channel is dredged underwater to the design mudline (7).

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