A diaphragm wall foundation type retaining structure close to a river and a construction method thereof

Abstract

The application discloses a diaphragm wall foundation type retaining structure close to a river and a construction method thereof, which comprises a foundation unit, a transverse partition connecting wall, a retaining wall and a backfill soil layer; the foundation unit comprises two wing walls; any wing wall comprises a main body part arranged along the length direction of the river and a convex part vertically arranged at the middle part; the two wing walls jointly form a convex structure; the convex parts of the two wing walls are opposite to each other and are arranged at intervals; the transverse partition connecting wall is connected with the two convex parts at two ends and is provided with a concrete hidden beam at the lower part along the length direction; the reserved steel bars at the two ends of the steel bar cage form a socket connection structure with the reserved steel bars of the adjacent wing wall steel bar cage; the retaining wall and the backfill soil layer. The convex wing wall and the linear transverse partition connecting wall are matched to form a stable underground anti-scour foundation through the steel bar socket connection structure; the construction process that the wing wall is first grooved and then the slow-setting concrete is poured can effectively avoid the formation of cold joints of the concrete structure, and can improve the construction quality and construction stability while controlling the construction material cost.

Description

Technical Field

[0001] This invention relates to the field of basic engineering technology. More specifically, this invention relates to a diaphragm wall foundation retaining structure adjacent to a river and its construction method. Background Technology

[0002] For retaining walls located adjacent to river channels, the impact of river flow on the banks can easily lead to insufficient bending and shear resistance, foundation cracking causing failure of the support structure, and soil erosion behind the wall. Therefore, the underground foundation of retaining walls generally adopts a diaphragm wall form, together forming a retaining support structure that achieves both erosion prevention and soil retention. Existing retaining support structures typically include the following forms: A "single-line" retaining structure refers to a single retaining wall and diaphragm wall arranged directly parallel to the riverbank. This type of retaining structure has a low flexural modulus, and the lateral soil pressure at the top acts entirely on the wall surface. This structure cannot utilize the soil's own weight to create a favorable anti-overturning moment, resulting in poor overturning resistance at the top. To achieve greater resistance to sliding and overturning under river impact and scouring, a longer wall structure or additional auxiliary reinforcement measures are needed to anchor the bottom of the diaphragm wall into the bedrock. This approach involves a large amount of construction work, a long construction period, and high material and construction costs.

[0003] Double-wall foundation retaining structures, such as patent CN117802936A, feature two or three diaphragm walls along the outer side of the riverbank. Plain concrete connecting walls are installed between these diaphragm walls. A cover plate is installed on the upper surface of both the diaphragm wall wing walls and the transverse connecting walls. The outer end of the cover plate is connected to the lower horizontal bend of the concrete slope protection via a water-stopping connection. Due to its embedment design, the transverse connecting walls in this double-wall structure are at the same depth as the wing walls, resulting in a significant increase in the amount of structural concrete used. Furthermore, in actual construction, if the diaphragm connecting wall and wing wall are constructed simultaneously, the entire structure needs to be trenched in an I-shape. This results in problems such as excessive trenching time and easy hole collapse after trenching, especially in sandy gravel strata or at the junction of two trenches. Even with jet grouting piles for trench wall reinforcement, hole collapse is still likely, hindering subsequent construction. If the diaphragm connecting wall and wing wall are constructed separately, the diaphragm connecting wall is made of plain concrete and lacks a hidden beam for steel reinforcement anchorage with the wing wall. The diaphragm connecting wall cannot transfer bending moment and shear force, failing to form an I-shaped load-bearing structure, significantly reducing its resistance to water flow impact, especially at the embedded end where the stress is greatest. In addition, this patent uses a cover plate connection at the top of the diaphragm wall for force transmission. Under the same force transmission requirements, the plate structure is thicker, leading to an increase in the amount of reinforced concrete. Moreover, the retaining structure (slope protection) uses a concrete facing, completely wasting the space at the top of the erosion control wall. Furthermore, the slope protection structure occupies a large amount of land on the bank, resulting in poor land use efficiency and economic benefits.

[0004] The double T-shaped diaphragm wall foundation retaining structure, such as patent CN119465860A, has a retaining wall foundation consisting of an H-shaped structure composed of two T-shaped walls. The joint between the transverse diaphragm walls is connected by a plug joint. That is, I-beams are set from top to bottom at the joint of the T-shaped wall, and steel mesh extends from its flanges. The mesh is connected to the steel cage to form a whole. One problem is that since the entire connector is cast into the concrete along with the reinforcing cage, the I-beams that house the connectors cannot be pulled out, making it impossible to reuse the connectors. The plug-in parts on the reinforcing cage are inserted between the two flanges of the corresponding connector's I-beam and the two reinforcing meshes extending from those flanges, resulting in a large number of lapped reinforcing bars at the main reinforcement lap joints. This requires a significant amount of lap joint materials, leading to high costs and low construction efficiency. Furthermore, after the connectors are lowered into the trench via the I-beams, their elevation cannot be strictly controlled to within the 10mm required by the specifications, unlike the reinforcing cage. This easily leads to misalignment of the lapped reinforcing bars at the joints, preventing effective force transmission. Meanwhile, the double-T diaphragm wall adopts a phased trenching and concrete pouring process, inevitably forming cold joints in the concrete structure at the joints. This leads to unstable load transfer in the reinforced concrete structure, severely affecting the forming quality and structural reliability of the diaphragm wall foundation. The bearing capacity of the diaphragm wall foundation must be multiplied by a large reduction factor, failing to fully utilize its structural performance, resulting in wasted wall sections and reinforcement, and poor economic efficiency. Furthermore, due to the large trench length of the transverse connection section of the T-shaped diaphragm wall and the excessive trenching time, significant stress concentration occurs at the intersection of the two trenches. Especially in sandy and gravelly soil conditions, this still easily leads to hole collapse, preventing successful trenching and hindering subsequent construction. In addition, the retaining structure uses a "Z"-shaped cantilever retaining wall, which only connects to the top cap beam of the diaphragm wall on the side furthest from the riverbank. This fails to fully utilize the upper connecting structure of the diaphragm wall foundation, resulting in insufficient retaining stability. Moreover, the empty space at the top of the diaphragm wall can only be used for low-requirement purposes such as pedestrian walkways, and cannot be used for vehicular traffic or building foundations, resulting in poor space utilization.

[0005] To address the aforementioned issues, it is necessary to design a diaphragm wall-based retaining structure that is located adjacent to the river channel. This structure should control the cost of construction materials while improving construction quality and stability throughout the entire construction process, thus ensuring the retaining capacity and the reliability of the support structure. Summary of the Invention

[0006] The purpose of this invention is to provide an I-shaped diaphragm wall foundation retaining wall adjacent to a river and its construction method. The convex wing wall and the straight transverse diaphragm connecting wall are connected by a steel reinforcement splice structure to form a stable underground anti-scour foundation. Combined with the construction process of first forming the wing wall trench and then using slow-setting concrete for pouring, the formation of cold joints in the concrete structure can be effectively avoided. While controlling the construction material cost, the construction quality and stability are improved, ensuring the retaining capacity and support reliability of the retaining structure.

[0007] To achieve these objectives and other advantages according to the present invention, a diaphragm wall foundation retaining structure adjacent to a river channel is provided, comprising: Multiple basic units are continuously arranged along the length of the river channel. Each basic unit is an I-shaped structure, including two wing walls. Each wing wall includes a main body and a protruding part. The main body is arranged along the length of the river channel, and the protruding part is vertically arranged in the middle of the main body and together with it in the horizontal direction to form a convex structure. The protruding parts of the two wing walls are opposite each other and spaced apart. A transverse diaphragm connecting wall is a straight structure arranged between the two wing walls. The two ends of the transverse diaphragm connecting wall are respectively connected to the protruding parts of the two wing walls. The lower part of the transverse diaphragm connecting wall is provided with a concrete hidden beam along the length direction. The reserved steel bars at both ends of the beam and the reserved steel bars of the adjacent wing wall steel cage form a socket connection structure and are connected as a whole by concrete. A retaining wall, which is set on top of multiple wing walls on the side of the multiple foundation units closest to the river along the length of the river channel; The backfill soil layer is laid on top of the multiple foundation units and fills the space on the side of the retaining wall away from the river channel. For any basic unit, the two wing walls are first constructed by forming grooves and pouring slow-setting concrete, and the transverse connecting wall is then constructed by forming grooves and connecting it to the two wing walls with ordinary concrete to form an integral I-shaped structure.

[0008] Preferably, in the diaphragm wall foundation retaining structure adjacent to the river channel, the end face of the protrusion adjacent to the transverse diaphragm connecting wall is recessed inward in the middle to form a zigzag groove, which is provided through the height direction of the protrusion. The reserved reinforcing bars of the wing wall reinforcement cage are provided inside the protrusion along the length direction and are located on both sides of the zigzag groove. The reserved reinforcing bars at both ends of the concrete hidden beam reinforcement cage are located inside the transverse diaphragm connecting wall and extend into the zigzag groove of the corresponding wing wall protrusion.

[0009] Preferably, the diaphragm wall foundation retaining structure adjacent to the river channel includes a main steel cage for the wing wall, which is set inside the main body of the corresponding wing wall and adapted to its shape and structure; two sets of first reserved steel bars, which are set opposite to each other on both sides of the protrusion of the corresponding wing wall. Each set of first reserved steel bars includes multiple L-shaped horizontal bars, which correspond to the concrete hidden beam and are spaced apart along its height direction. One horizontal side of any L-shaped horizontal bar is fixed to the main steel cage, and the other horizontal side extends into the interior of the protrusion along its length direction and extends to the opening end of the zigzag groove. Each L-shaped horizontal bar is fixedly connected by multiple first vertical bars to form a sheet structure. The concrete concealed beam's reinforcing cage includes a concealed beam reinforcing cage, which is set inside the concrete concealed beam and adapted to its shape and structure; two sets of second reserved reinforcing bars, which are respectively set at both ends of the concealed beam reinforcing cage. Each set of second reserved reinforcing bars includes two reinforcing meshes, which are set opposite to each other on both sides of the concealed beam reinforcing cage. Each reinforcing mesh includes multiple extending horizontal bars, which are spaced apart along the height direction of the concealed beam reinforcing cage. One end of each extending horizontal bar is fixedly connected to the inner side of the concealed beam reinforcing cage, and the other end extends into the corresponding Z-shaped groove along the length direction of the transverse connecting wall. Each extending horizontal bar is fixedly connected by multiple second vertical bars to form a reinforcing mesh.

[0010] Preferably, in the diaphragm wall foundation retaining structure adjacent to the river channel, the steel mesh and the adjacent set of first reserved steel bars are respectively arranged on the inner and outer sides of the same side wall of the zigzag groove, and the multiple extended horizontal bars of the steel mesh are arranged one-to-one with the multiple L-shaped horizontal bars of the set of first reserved steel bars.

[0011] Preferably, in the diaphragm wall foundation retaining structure adjacent to the river, the plurality of first vertical bars are divided into two rows of first vertical bars, which are respectively set on both sides of the horizontal side of the corresponding L-shaped horizontal bar located inside the protrusion. Any row of first vertical bars is spaced apart along the length direction of the corresponding horizontal side, and any first vertical bar is set along the height direction of the concrete hidden beam and fixedly connected to the corresponding plurality of L-shaped horizontal bars. The plurality of second vertical bars are spaced apart along the length of the concrete hidden beam outside the U-shaped groove, and any second vertical bar is arranged along the height of the concrete hidden beam and fixedly connected to the corresponding plurality of extended horizontal bars.

[0012] Preferably, in the diaphragm wall foundation retaining structure adjacent to the river channel, the length of the protrusion in the length direction of the transverse diaphragm wall is less than or equal to one meter.

[0013] Preferably, the diaphragm wall foundation retaining structure adjacent to the river channel includes a capping beam in the foundation unit, which is correspondingly set on the top of the two wing walls and the transverse diaphragm connecting wall to form an I-shaped beam structure. The capping beam includes two transverse beams, which are respectively set on the top of the corresponding two wing walls; and a longitudinal beam, which is set on the top of the corresponding transverse diaphragm connecting wall and connects the two transverse beams along its length direction; and multiple transverse beams located on the same side of the longitudinal beam in the multiple foundation units are sequentially connected along the length direction of the river channel.

[0014] Preferably, the diaphragm wall foundation retaining structure adjacent to the river channel has a concrete tie plate between any two adjacent cap beams, which fills the square slot formed between the two cap beams and together with the two cap beams forms a supporting plane.

[0015] This invention also provides a construction method for a diaphragm wall foundation retaining structure adjacent to a river channel, comprising: S1. Construct the diaphragm walls and guide walls of each foundation unit in the construction area according to the design drawings; S2. Starting from a basic unit, its two wing walls are constructed as the first construction section (using two trenching machines to simultaneously form the trench); S3. Locking pipe joint boxes are placed at both ends of the groove corresponding to the main body of each wing wall, and a Z-shaped steel plate is placed at the outer end of the groove corresponding to the protrusion of each wing wall as a partition plate for the socket connection structure. The central protrusion of the Z-shaped steel plate is set facing the inner side of the protrusion. The extension plates on both sides of the central protrusion are set parallel to the outer end face of the groove corresponding to the protrusion and abut against its inner side wall. S4. Guided by the lock joint box and the Z-shaped steel plate, lower the wing wall reinforcement cage into the trench section to be constructed first, with the reserved reinforcement extending into the side plate of the Z-shaped steel plate and the inner wall of the trench section corresponding to the protrusion. S5. Using the lock joint box and the Z-shaped steel plate as boundaries, pour the wing wall concrete with slow-setting concrete. S6. After the slow-setting concrete is poured, the transverse diaphragm connecting wall is immediately formed as the subsequent construction section, and the subsequent construction section connects the two previously constructed sections. S7. Using the Z-shaped steel plates located at both ends of the trench section to be constructed later as a guide, the concrete hidden beam reinforcement cage is lowered to a set height position, and the reserved steel bars of the concrete hidden beam reinforcement cage extend into the middle protrusion of the Z-shaped steel plate. S8. Pull up the Z-shaped steel plates at both ends, and simultaneously pour ordinary concrete to build the transverse diaphragm connecting wall concrete as the Z-shaped steel plates are lifted, so that the bottom of the Z-shaped steel plates is within a set distance range above the concrete pouring liquid surface, and pull up the lock joint boxes at both ends simultaneously after a set time. S9. Repeat steps S2-S9 to construct the next adjacent foundation unit until all diaphragm walls are constructed. S10. Along the length of the river channel, break down the connecting walls and guide walls in sequence, construct a retaining wall on the top of the wing wall on the side closest to the river channel, and then backfill soil behind the retaining wall to form the ground.

[0016] Preferably, in the construction method of the I-shaped diaphragm wall foundation retaining wall adjacent to the river, in S3, after the Z-shaped steel plate is lowered, a protective box is placed in the Z-shaped groove formed by the central protrusion, which is the same height as the Z-shaped steel plate and the cross-sectional structure is adapted to the Z-shaped groove; in S6, the protective box needs to be pulled out after the transverse diaphragm connecting wall is grooved.

[0017] The present invention has at least the following beneficial effects: 1. The retaining wall underground foundation unit of the present invention is an I-shaped anti-scour wall composed of two U-shaped diaphragm walls (wing walls) and one straight diaphragm wall (transverse diaphragm connecting wall). Its bending modulus is greatly increased compared with single or multiple walls, which strengthens the resistance to water flow impact and lateral earth pressure after scour. It also improves the overturning and sliding resistance of the diaphragm wall when it is directly used as a retaining wall after water flow scour. The connection node between the wing wall and the transverse diaphragm connecting wall adopts the form of steel reinforcement socket connection structure. The transverse diaphragm connecting wall only sets steel reinforcement structure at the concrete hidden beam. The effective utilization rate of structural materials is high, which greatly reduces the amount of steel reinforcement binding construction and the cost of steel reinforcement materials. 2. In this invention, due to the presence of the concrete hidden beam, the transverse diaphragm connecting wall does not need to be at the same depth as the wing wall. The height of the concrete hidden beam is calculated based on structural stability and bearing capacity, and it can cover the most unfavorable stress point at the embedded end of the anti-scour wall, which further saves a lot of material and labor costs and improves construction efficiency. 3. In this invention, the two wing walls are first grooved and constructed using slow-setting concrete. The transverse connecting wall is then grooved and constructed using ordinary concrete. When the transverse connecting wall is grooved and ordinary concrete is poured, the concrete at the protrusion is not yet fully set. The two different concretes can be better connected as one, and the connection strength and stability are guaranteed under the action of the socket connection structure, forming an I-shaped structure that can effectively transmit force. At the same time, it effectively avoids the generation of cold joints in the concrete structure, so that the formed I-shaped diaphragm wall has strong integrity, no reduction in load-bearing capacity, good anti-slip and anti-overturning stability, and a small anchoring depth required at the bottom. 4. Compared with traditional plate connections, the I-shaped diaphragm wall of the present invention adopts a crown beam and a concrete tie plate to form a beam-plate connection structure, which has a higher structural utilization rate. The crown beam is set on the top of the wing wall and the transverse diaphragm connection wall, which greatly reduces the thickness of the tie plate in the middle, further saving reinforced concrete materials and labor. 5. The retaining wall of this invention, together with the capping beam and concrete tie plate, forms an L-shaped retaining wall structure. The weight of the backfill soil behind the wall presses on the L-shaped retaining wall, generating a favorable overturning moment. The retaining wall and the backfill soil behind the wall form a usable space on land, which not only ensures the stress performance and overturning resistance of the retaining structure, but also saves land occupation and helps control construction costs. At the same time, with the help of the capping beam, the diaphragm wall serves as the foundation of the retaining wall, which greatly increases the embedment depth of the retaining wall and further enhances the overturning resistance of the retaining wall.

[0018] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0019] Figure 1This is a schematic diagram of the elevation construction structure of a diaphragm wall foundation retaining structure adjacent to a river channel, according to an embodiment of the present invention. Figure 2 This is a schematic diagram of the AA cross-section of the diaphragm wall foundation retaining structure adjacent to the river described in the above embodiments. Figure 3 This is a schematic diagram of the BB cross-section of the diaphragm wall foundation retaining structure adjacent to the river described in the above embodiments. Figure 4 This is a schematic diagram of the CC cross-section of the diaphragm wall foundation retaining structure adjacent to the river described in the above embodiment. Figure 5 This is a schematic diagram of the DD cross-sectional structure of the diaphragm wall foundation retaining structure adjacent to the river described in the above embodiments. Figure 6 A schematic diagram of the plan construction structure of the diaphragm wall foundation retaining structure adjacent to the river in the above embodiment; Figure 7 This is a schematic diagram of the arrangement of the first reserved reinforcing bar in the above embodiment; Figure 8 This is a schematic diagram of the arrangement of the second reserved reinforcing bar in the above embodiment; Figure 9 This is a schematic diagram of the planar construction structure of the socket connection structure described in the above embodiments; Figure 10 This is a schematic diagram of the planar construction structure of S1 in a construction method of a diaphragm wall foundation retaining structure adjacent to a river channel according to an embodiment of the present invention. Figure 11 This is a schematic diagram of the planar construction structure of S2 in the above embodiment; Figure 12 This is a schematic diagram of the planar construction structure of S3 in the above embodiment; Figure 13 This is a schematic diagram of the planar construction structure of S4 in the above embodiment; Figure 14 This is a schematic diagram of the planar construction structure of S5 in the above embodiment; Figure 15 This is a schematic diagram of the planar construction structure of S6 in the above embodiment; Figure 16 This is a schematic diagram of the planar construction structure of S7 in the above embodiment; Figure 17 This is a schematic diagram of the isometric construction structure of S7 in the above embodiment; Figure 18 This is a schematic diagram of the planar construction structure of S8 in the above embodiment; Figure 19 This is a schematic diagram of the isometric construction structure of S9 in the above embodiment; Figure 20 This is an isometric view of the connection structure between the cap beam and the concrete tie plate described in the above embodiments; Figure 21 This is a schematic diagram of the isometric construction structure of S10 in the above embodiment.

[0020] Explanation of reference numerals in the attached figures: 1. Basic unit; 11. Wing wall; 111. Main body; 112. Protrusion; 113. Main reinforcement cage; 114. L-shaped horizontal reinforcement; 115. First vertical reinforcement; 12. Transverse diaphragm connecting wall; 121. Concrete hidden beam; 122. Hidden beam reinforcement cage; 123. Extended horizontal reinforcement; 124. Second vertical reinforcement; 13. Crown beam; 14. Concrete tie plate; 2. Retaining wall; 21. Drainage hole; 22. Embedded reinforcement; 3. Backfill soil layer; 4. Retarded concrete; 5. Ordinary concrete; 6. Riverbank; 7. Maximum scour line; 81. Z-shaped steel plate; 82. Protective box; 83. Wooden wedge. Detailed Implementation

[0021] The present invention will now be described in further detail with reference to the accompanying drawings, so that those skilled in the art can implement it based on the description.

[0022] It should be noted that, unless otherwise specified, the experimental methods described in the following embodiments are all conventional methods, and the reagents and materials described are all commercially available unless otherwise specified. In the description of this invention, the terms "lateral", "longitudinal", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" 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.

[0023] like Figure 1-5 As shown, the present invention provides a diaphragm wall foundation retaining structure adjacent to a river channel, comprising: Multiple basic units are continuously arranged along the length of the river channel. Each basic unit is an I-shaped structure, including two wing walls. Each wing wall includes a main body and a protruding part. The main body is arranged along the length of the river channel, and the protruding part is vertically arranged in the middle of the main body and together with it in the horizontal direction to form a convex structure. The protruding parts of the two wing walls are opposite each other and spaced apart. A transverse diaphragm connecting wall is a straight structure arranged between the two wing walls. The two ends of the transverse diaphragm connecting wall are respectively connected to the protruding parts of the two wing walls. The lower part of the transverse diaphragm connecting wall is provided with a concrete hidden beam along the length direction. The reserved steel bars at both ends of the beam and the reserved steel bars of the adjacent wing wall steel cage form a socket connection structure and are connected as a whole by concrete. A retaining wall, which is set on top of multiple wing walls on the side of the multiple foundation units closest to the river along the length of the river channel; The backfill soil layer is laid on top of the multiple foundation units and fills the space on the side of the retaining wall away from the river channel. For any basic unit, the two wing walls are first constructed by forming grooves and pouring slow-setting concrete, and the transverse connecting wall is then constructed by forming grooves and connecting it to the two wing walls with ordinary concrete to form an integral I-shaped structure.

[0024] In the above technical solution, multiple wing walls located on the same side of the transverse diaphragm connecting wall in the multiple foundation units are sequentially connected along the length of the river channel. This allows the multiple foundation units to form a continuous underground wall covering the entire design and construction area after construction, providing a solid and reliable support foundation for the retaining wall and backfill layer above. The underground foundation unit of the retaining wall is an I-shaped scour barrier composed of two U-shaped diaphragm walls (wing walls) and one straight diaphragm wall (transverse diaphragm connecting wall). Its flexural modulus is greatly increased compared to single or multiple walls, resulting in strong resistance to water flow impact and lateral earth pressure after scouring. It also improves the overturning and sliding resistance of the diaphragm wall when directly used as a retaining wall after water scouring.

[0025] The transverse diaphragm connecting wall is supported by an internal concrete concealed beam. This concealed beam is located at the lower part of the transverse diaphragm connecting wall (but not at the bottom end) and is connected to the diaphragm wall wing wall using a reinforced steel socket structure to form a whole. Specifically, the reinforcement cage of the concrete concealed beam is adapted to the structural form of the concrete concealed beam and installed at the corresponding (height) position. The reserved reinforcement bars of the concrete concealed beam reinforcement cage extend outwards along the length of the concrete concealed beam (near the two wing walls). The wing wall reinforcement cage is mainly designed for the main body, and its structural form is adapted to the main body. The reserved reinforcement bars of the wing wall reinforcement cage are correspondingly set in the protrusions of the concrete concealed beam and cooperate with the reserved reinforcement bars of the concrete concealed beam reinforcement cage to form a socket connection structure. The two types of reserved reinforcement bars are fixed to the wing wall reinforcement cage and the concrete concealed beam reinforcement cage respectively, and can be naturally connected into a whole when the concrete of the wing wall and the transverse diaphragm connecting wall is poured. This type of reinforced steel socket connection structure means that the transverse diaphragm connecting wall only needs to have a reinforcement structure at the concrete concealed beam, resulting in high effective utilization of structural materials and greatly reducing the amount of reinforcement binding work and the cost of reinforcement materials. Concrete concealed beams can be installed 1 meter above the bottom elevation of the transverse diaphragm connecting wall, with the top elevation of the concrete concealed beams located 0.5-1 meter below the maximum scour mud surface line. Not installing the concrete concealed beams at the bottom of the transverse diaphragm connecting wall prevents excessive sediment and inferior concrete from flowing into and adhering to the beam area, improving the overall quality of the diaphragm wall and avoiding load-bearing capacity reduction caused by inferior concrete. Furthermore, due to the presence of the concrete concealed beams, the transverse diaphragm connecting wall does not need to be at the same depth as the wing wall. The height of the concrete concealed beams is determined through structural stability and load-bearing capacity calculations, covering the most unfavorable stress point at the embedded end of the scour wall (approximately one-tenth of the total height of the diaphragm wall), further saving significant material and labor costs and improving construction efficiency.

[0026] The retaining wall and the backfill soil layer behind it form a usable space on land. The top surface of the backfill soil layer is flush with the ground on the riverbank and can be used as a driving or building space as part of the ground. Thus, it not only ensures the stress performance and overturning resistance of the retaining structure, but also saves land occupation, eliminates the need for slope protection structure, helps control construction costs, and has good economic benefits.

[0027] Furthermore, because the wing walls are pre-grooved and poured with slow-setting concrete, the concrete in the protruding section has not yet fully set when the transverse diaphragm connecting wall is grooved and poured with ordinary concrete. This allows the two different concrete sections to better bond together, ensuring connection strength and stability under the action of the socket connection structure, forming an I-shaped structure that can effectively transmit force. Simultaneously, it effectively avoids the formation of cold joints in the concrete structure, resulting in a well-formed I-shaped diaphragm wall with strong integrity, no reduction in load-bearing capacity, good anti-slip and anti-overturning stability, and a small required anchorage depth at the bottom. Moreover, the wing wall protrusions are of limited length, and the sequential groove-grooving and pouring method for the wing walls and transverse diaphragm connecting walls greatly reduces the risk of excessively long transverse groove-grooving time and the formation of large stress concentrations at the intersections of groove sections in different directions (transverse and longitudinal), avoiding problems such as hole collapse, improving construction safety, and ensuring construction quality and efficiency.

[0028] In another technical solution, in the diaphragm wall foundation retaining structure adjacent to the river channel, the end face of the protrusion adjacent to the transverse diaphragm connecting wall is recessed inward in the middle to form a zigzag groove, which is arranged through the height direction of the protrusion. The reserved steel bars of the wing wall steel cage are arranged inside the protrusion along the length direction and are located on both sides of the zigzag groove. The reserved steel bars at both ends of the concrete hidden beam steel cage are located inside the transverse diaphragm connecting wall and extend into the zigzag groove of the corresponding wing wall protrusion. Therefore, the reserved reinforcing bars of the wing wall reinforcement cage and the reserved reinforcing bars of the concrete hidden beam reinforcement cage can jointly form a reasonable socket connection structure on both the inner and outer sides of the U-shaped groove. After the concrete is poured, the reserved reinforcing bars outside the U-shaped groove form the connection structure of the concrete hidden beam reinforcement cage and are integrated with the wing wall reinforcement cage to form an effective and reliable overall load-bearing and force-transmitting structure. Under the condition of ensuring connection stability, the material usage at the joint is effectively reduced. Moreover, the socket connection structure does not require additional binding construction between the reserved reinforcing bars belonging to different reinforcement cages, further simplifying the construction process, reducing the amount of manual labor, and lowering the construction cost.

[0029] In actual construction, before pouring concrete for the wing wall, temporary measures can be used to separate the outer ends of each protrusion. After the wing wall concrete is poured, the required zigzag groove will be formed. When pouring concrete for the transverse diaphragm connecting wall, the temporary measures can be removed simultaneously with the concrete pouring.

[0030] The temporary measure can be a Z-shaped steel plate, which is designed to fit the outer end of the protrusion according to the Z-shaped groove, forming a closed structure. This allows the Z-shaped groove to naturally form as a boundary during the pouring of the wing wall concrete. Furthermore, a rectangular steel pipe can be installed on the outside of the Z-shaped steel plate (near the transverse diaphragm connecting wall) as a protective box to support the steel plate. The rectangular steel pipe is fitted within the Z-shaped groove to prevent concrete turbulence behind the steel plate from causing it to sway or deform, or to prevent the wing wall concrete from intruding into the corresponding groove area of ​​the transverse diaphragm connecting wall. Simultaneously, the length of the rectangular steel pipe along the transverse diaphragm connecting wall can be slightly greater than the depth of the Z-shaped groove, allowing the outer end of the rectangular steel pipe to extend beyond the Z-shaped groove. In this case, wooden wedges can be installed on both sides of the top of the protective box (rectangular steel pipe) to fill the gap between the rectangular steel pipe and the upper diaphragm wall guide wall, ensuring the reliability and stability of the temporary measure.

[0031] In another technical solution, the diaphragm wall foundation retaining structure adjacent to the river channel includes a main steel cage for the wing wall, which is set inside the main body of the corresponding wing wall and adapted to its shape and structure; two sets of first reserved steel bars, which are set opposite to each other on both sides of the protrusion of the corresponding wing wall. Each set of first reserved steel bars includes multiple L-shaped horizontal bars, which correspond to the concrete hidden beam and are spaced apart along its height direction. One horizontal side of any L-shaped horizontal bar is fixed to the main steel cage, and the other horizontal side extends into the interior of the protrusion along its length direction and extends to the opening end of the zigzag groove. Each L-shaped horizontal bar is fixedly connected by multiple first vertical bars to form a sheet structure. The concrete concealed beam's reinforcing cage includes a concealed beam reinforcing cage, which is set inside the concrete concealed beam and adapted to its shape and structure; two sets of second reserved reinforcing bars, which are respectively set at both ends of the concealed beam reinforcing cage. Each set of second reserved reinforcing bars includes two reinforcing meshes, which are set opposite to each other on both sides of the concealed beam reinforcing cage. Each reinforcing mesh includes multiple extending horizontal bars, which are spaced apart along the height direction of the concealed beam reinforcing cage. One end of each extending horizontal bar is fixedly connected to the inner side of the concealed beam reinforcing cage, and the other end extends into the corresponding Z-shaped groove along the length direction of the transverse connecting wall. Each extending horizontal bar is fixedly connected by multiple second vertical bars to form a reinforcing mesh.

[0032] The first reserved reinforcing bars are correspondingly arranged with the concrete concealed beam, meaning that the top of each group of first reserved reinforcing bars is located at the top of the designed position of the concrete concealed beam, and the bottom of each group of first reserved reinforcing bars is located at the bottom of the designed position of the concrete concealed beam. The first reserved reinforcing bars are fixed to the main reinforcing cage by binding, and the second reserved reinforcing bars are fixed to the concealed beam reinforcing cage by binding and overlapping. The two reinforcing meshes and the two corresponding (protruding) groups of first reserved reinforcing bars are separated by the edge line of the "Z"-shaped groove and together form the socket connection structure.

[0033] In another technical solution, for the diaphragm wall foundation type earth-retaining support structure adjacent to a river channel, the steel mesh and a group of adjacent first reserved steel bars are respectively arranged on the inner and outer sides of the same side wall of the zigzag-shaped groove, and the plurality of extending horizontal steel bars of the steel mesh and the plurality of L-shaped horizontal steel bars of the group of first reserved steel bars are arranged in one-to-one correspondence.

[0034] Specifically, the corresponding extending horizontal steel bars and L-shaped horizontal steel bars are located at the same height position and arranged at parallel intervals on the inner and outer sides of the side wall of the zigzag-shaped groove, and can be connected to form a more reasonable and stable integral stress structure during concrete pouring.

[0035] In another technical solution, for the diaphragm wall foundation type earth-retaining support structure adjacent to a river channel, the plurality of first vertical steel bars are divided into two rows of first vertical steel bars, which are respectively arranged on both sides of the horizontal edge of the corresponding L-shaped horizontal steel bar located inside the protruding portion, any row of first vertical steel bars is arranged at intervals along the length direction of the corresponding horizontal edge, and any first vertical steel bar is arranged along the height direction of the concealed concrete beam and is fixedly connected to the corresponding plurality of L-shaped horizontal steel bars; the plurality of second vertical steel bars are arranged at intervals along the length direction of the concealed concrete beam outside the zigzag-shaped groove, and any second vertical steel bar is arranged along the height direction of the concealed concrete beam and is fixedly connected to the corresponding plurality of extending horizontal steel bars.

[0036] As a more preferable implementation solution, the second vertical steel bars are arranged between the extending horizontal steel bars and the reinforcement cage of the concealed beam, so that Figure 9 as shown, the positions of the second vertical steel bars and the first vertical steel bars located between two groups of L-shaped horizontal steel bars in the width direction of the transverse connecting wall (concealed concrete beam) coincide and correspond as much as possible, so that the concrete pouring of different structures (wing wall, transverse connecting wall) can be better connected into a whole through the socket connection structure, and has good stress stability.

[0037] In another technical solution, for the diaphragm wall foundation type earth-retaining support structure adjacent to a river channel, the length of the protruding portion in the length direction of the transverse connecting wall is less than or equal to one meter.

[0038] The above technical solution effectively reduces the trenching time by further limiting the transverse (protruding portion) trenching length of the wing wall, and the transverse trench section can be quickly formed together with the main body during pouring, which avoids problems such as hole collapse caused by great stress concentration at the intersection of two trenches, and further ensures the stability of the soil structure during trenching and construction. The sequential trenching and pouring structure of the convex wing wall and the straight transverse connecting wall can have lower trenching risk and higher success rate even under sandy pebble stratum conditions, effectively ensuring construction quality and construction efficiency, also avoiding expensive trench wall reinforcement measures, which is conducive to controlling construction costs.

[0039] In another technical solution, the diaphragm wall foundation retaining structure adjacent to the river channel includes a capping beam in the foundation unit. The capping beam is correspondingly set on the top of the two wing walls and the transverse diaphragm connecting wall to form an I-shaped beam structure. The capping beam includes two transverse beams, which are respectively set on the top of the two corresponding wing walls; and a longitudinal beam, which is set on the top of the corresponding transverse diaphragm connecting wall and connects the two transverse beams along its length. In the multiple foundation units, multiple transverse beams located on the same side of the longitudinal beam are sequentially connected along the length of the river channel.

[0040] Specifically, the base of the retaining wall and the capping beam on the corresponding wing wall are anchored together by pre-embedded steel bars. The ground behind the retaining wall is backfilled to form the riverbank ground. The backfill layer is adaptively supported on the remaining capping beam structure, so that the underground continuous wall (foundation unit) structure and the above-ground retaining structure (retaining wall and backfill layer) form a more stable whole, and enhance the retaining support effect.

[0041] In another technical solution, the diaphragm wall foundation retaining structure adjacent to the river channel has a concrete tie plate between any two adjacent cap beams. The tie plate fills the square slot formed between the two cap beams and together with the two cap beams forms a supporting plane.

[0042] In the above technical solution, the thickness of the concrete tie plate is equal to the height difference between the top surface of the capping beam and the existing ground between the foundation units. The concrete tie plate and the capping beam together form a complete plane on the top of the foundation unit, providing a reliable foundation for the construction of the retaining wall and backfill layer. The empty slots on the outside of the capping beam of the foundation units at both ends (the side without adjacent foundation units) are also adaptively filled by the concrete tie plate to ensure that the retaining support structure is flat with the surrounding ground and has no height difference. The capping beam and the concrete tie plate together form a beam-slab system, which serves as the base slab of the retaining wall and together with the retaining wall forms an L-shaped retaining wall structure. The weight of the backfill soil behind the wall presses on the L-shaped retaining wall, generating a favorable overturning moment. The retaining wall and the backfill soil behind the wall form usable land space, which not only ensures the structural performance and overturning resistance of the retaining structure, but also saves land occupation, eliminates the need for a slope protection structure, and helps control construction costs. At the same time, with the connection of the capping beam, the diaphragm wall serves as the foundation of the retaining wall, which greatly increases the embedment depth of the retaining wall and further enhances the overturning resistance of the retaining wall.

[0043] Compared to traditional plate connections, the I-shaped diaphragm wall of this invention uses a cap beam and a concrete tie plate to form a beam-plate connection structure, which has a higher structural utilization rate. The cap beam is set on the top of the wing wall and the transverse diaphragm connection wall, which greatly reduces the thickness of the tie plate in the middle (which can be reduced to 120~150mm), further saving reinforced concrete materials and labor.

[0044] The present invention also provides a construction method for the diaphragm wall foundation retaining structure adjacent to the river channel, comprising: S1. Construct the diaphragm walls and guide walls of each foundation unit in the construction area according to the design drawings; S2. Starting from a basic unit, its two wing walls are constructed as the first construction section (using two trenching machines to simultaneously form the trench); S3. Locking pipe joint boxes are placed at both ends of the groove corresponding to the main body of each wing wall, and a Z-shaped steel plate is placed at the outer end of the groove corresponding to the protrusion of each wing wall as a partition plate for the socket connection structure. The central protrusion of the Z-shaped steel plate is set facing the inner side of the protrusion. The extension plates on both sides of the central protrusion are set parallel to the outer end face of the groove corresponding to the protrusion and abut against its (the groove's) inner sidewall. S4. Clean the trench section of the first construction section once, and then, guided by the lock joint box and the Z-shaped steel plate, lower the wing wall reinforcement cage into the trench section of the first construction section. The reserved reinforcement extends into the side plate of the Z-shaped steel plate and the inner wall of the trench section corresponding to the protrusion. S5. After cleaning the trench section twice, lower the wing wall guide pipe. Then, using the lock joint box and the Z-shaped steel plate as the boundary, pour the wing wall concrete with slow-setting concrete. At the same time, fill the over-excavated area behind the lock joint box with sand and gravel. Under the restriction of the Z-shaped steel plate, after the wing wall concrete is poured, a Z-shaped groove will naturally form at the outer end of the protrusion. The retarding time of the retarded concrete should be T hours, where T is the sum of the estimated trenching time of the transverse diaphragm connecting wall and the set delay time. The set delay time is determined based on the actual construction conditions (concrete pouring speed, the forming time of ordinary concrete, etc.) to ensure that the wing wall concrete is not completely set when the concrete of the transverse diaphragm connecting wall is poured, and that the two types of concrete are controlled to complete setting and solidification at similar times as much as possible. In this embodiment, the delay time is set to 6 hours.

[0045] S6. After the slow-setting concrete is poured, the transverse diaphragm connecting wall is immediately formed as the subsequent construction section, and the subsequent construction section connects the two previously constructed sections. S7. Using the Z-shaped steel plates located at both ends of the trench section to be constructed later as a guide, the concrete hidden beam reinforcement cage is lowered to a set height position, and the reserved steel bars of the concrete hidden beam reinforcement cage extend into the middle protrusion of the Z-shaped steel plate. During the lowering of the reinforcing cage, the concrete hidden beam reinforcing cage is suspended from the I-beam support spanning the transverse diaphragm connecting wall by three hanging bars spaced apart along its length. After the reinforcing cage is lowered, the reserved reinforcing bars of the concrete hidden beam reinforcing cage and the reserved reinforcing bars of the wing wall reinforcing cage should both be located within the height range of the concrete hidden beam and form a socket connection structure corresponding to the inside and outside of the U-shaped steel plate. The trench section to be constructed subsequently is then cleaned a second time.

[0046] S8. Pull up the Z-shaped steel plates at both ends, and simultaneously pour ordinary concrete to build the transverse diaphragm connecting wall concrete as the Z-shaped steel plates are lifted, so that the bottom of the Z-shaped steel plates is within a set distance range (1-2m) above the concrete pouring liquid surface, and pull up the locking pipe joint box at both ends simultaneously after a set time. In addition, after the concrete pouring of the transverse diaphragm wall has been completed for a set time, the lock joint boxes located at both ends of the main body of the wing wall can be slowly pulled out. The set time is determined according to the actual setting condition of the slow-setting concrete. In this embodiment, the set time is selected as 1-2 hours.

[0047] S9. Repeat steps S2-S9 to construct the next adjacent foundation unit until all diaphragm walls are constructed. Specifically, in the preceding step (S2), a foundation unit located at the beginning / end of multiple foundation units is usually selected as the starting point for construction, so that the construction of other foundation units can be completed sequentially along the length of the river channel; alternatively, a foundation unit located in the middle of multiple foundation units can be selected as the starting point for construction. After the construction of this foundation unit is completed, construction personnel are reasonably allocated to carry out symmetrical and synchronous construction of adjacent foundation units at both ends of this foundation unit, so as to further improve construction efficiency.

[0048] S10. Along the length of the river channel, break down the connecting walls and guide walls in sequence, construct a retaining wall on the top of the wing wall on the side closest to the river channel, and then backfill soil behind the retaining wall to form the ground. After the guide wall is demolished, I-shaped capping beams are first constructed on each I-shaped diaphragm wall (foundation unit), and concrete tie plates are used to fill the gaps formed between adjacent capping beams to form a support plane. Then, retaining walls and backfill soil layers are constructed based on this. In addition, after the guide wall of a single foundation unit is demolished, the capping beam, concrete tie plate, retaining wall and backfill layer at the top of the foundation unit are constructed first. Then the guide wall of the next foundation unit is demolished. The retaining wall and backfill layer above the adjacent foundation units are constructed in a cyclical manner. The retaining walls and backfill layers of each segment are connected sequentially along the length of the river channel until the entire retaining wall arranged along the riverbank is completed.

[0049] In another technical solution, in the construction method of the I-shaped diaphragm wall foundation retaining wall adjacent to the river, in S3, after the Z-shaped steel plate is lowered, a protective box is placed in the Z-shaped groove formed by the central protrusion. The protective box is at the same height as the Z-shaped steel plate and its cross-sectional structure is adapted to the Z-shaped groove. In S6, after the transverse diaphragm connecting wall is grooved, the protective box needs to be pulled out for wall brushing and hole cleaning.

[0050] In the above technical solution, the protective box supports the Z-shaped steel plate from the end near the transverse connecting wall, ensuring the stability and sealing of the Z-shaped steel plate during the pouring of the wing wall concrete, preventing the concrete from being disturbed in the first section of the wall, and preventing the trenching machine from directly colliding with the Z-shaped steel plate when trenching the subsequent section, thus preventing damage to the reserved steel bars of the wing wall reinforcement cage and the wing wall concrete.

[0051] Specifically, reusable rectangular steel pipes are used as protective boxes during construction. The length of the rectangular steel pipe in the transverse connecting wall direction can be slightly greater than the depth of the Z-shaped groove, so that the outer end of the rectangular steel pipe extends a certain length beyond the Z-shaped groove. The lifting hole of the protective box is located at three-quarters of the cross-section of the protective box, so that when the protective box is lifted and lowered into the middle protrusion of the Z-shaped steel plate, it tilts under the action of gravity, and the lower end is closer to the steel web than the upper end. This allows the lower end to be lowered tightly against the steel web, which is equivalent to using H-beams (side plates of the Z-shaped steel plate) for guidance and avoids collision with the reserved reinforcing bars of the wing wall reinforcement cage. When the protective box is finally lowered into place, the crane retracts the lifting rope to bring the top of the protective box close to the steel web. Wooden wedges are inserted into the gaps between the top two sides of the protective box protruding from the Z-shaped groove and the guide wall to fill the gaps between the rectangular steel pipe and the upper diaphragm wall guide wall. This effectively prevents the top of the joint box from shaking and shifting, ensuring the reliability and stability of the temporary separation measure used for pouring between the wing wall and the transverse diaphragm connecting wall.

[0052] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A diaphragm wall foundation retaining structure adjacent to a river channel, characterized in that, include: Multiple basic units are continuously arranged along the length of the river channel. Each basic unit is an I-shaped structure, including two wing walls. Each wing wall includes a main body and a protruding part. The main body is arranged along the length of the river channel, and the protruding part is vertically arranged in the middle of the main body and together with it in the horizontal direction to form a convex structure. The protruding parts of the two wing walls are opposite each other and spaced apart. A transverse diaphragm connecting wall is a straight structure arranged between the two wing walls. The two ends of the transverse diaphragm connecting wall are respectively connected to the protruding parts of the two wing walls. The lower part of the transverse diaphragm connecting wall is provided with a concrete hidden beam along the length direction. The reserved steel bars at both ends of the beam and the reserved steel bars of the adjacent wing wall steel cage form a socket connection structure and are connected as a whole by concrete. A retaining wall, which is set on top of multiple wing walls on the side of the multiple foundation units closest to the river along the length of the river channel; The backfill soil layer is laid on top of the multiple foundation units and fills the space on the side of the retaining wall away from the river channel. For any basic unit, the two wing walls are first constructed by forming grooves and pouring slow-setting concrete, and the transverse connecting wall is then constructed by forming grooves and connecting it to the two wing walls with ordinary concrete to form an integral I-shaped structure.

2. The diaphragm wall foundation retaining structure adjacent to a river channel as described in claim 1, characterized in that, The end face of the protrusion adjacent to the transverse diaphragm connecting wall is recessed inward in the middle to form a zigzag groove, which is provided through the height direction of the protrusion. The reserved steel bars of the wing wall steel cage are provided inside the protrusion along the length direction and are located on both sides of the zigzag groove. The reserved steel bars at both ends of the concrete hidden beam steel cage are located inside the transverse diaphragm connecting wall and extend into the zigzag groove of the corresponding wing wall protrusion.

3. The diaphragm wall foundation retaining structure adjacent to a river channel as described in claim 2, characterized in that, The wing wall reinforcement cage includes a main reinforcement cage, which is set inside the main body of the corresponding wing wall and adapted to its shape and structure; two sets of first reserved reinforcement bars, which are set opposite to each other on both sides of the protrusion of the corresponding wing wall. Each set of first reserved reinforcement bars includes multiple L-shaped horizontal bars, which correspond to the concrete hidden beam and are spaced apart along its height direction. One horizontal side of any L-shaped horizontal bar is fixed to the main reinforcement cage, and the other horizontal side extends into the interior of the protrusion along its length direction and extends to the opening end of the zigzag groove. Each L-shaped horizontal bar is fixedly connected by multiple first vertical bars to form a sheet structure. The concrete concealed beam's reinforcing cage includes a concealed beam reinforcing cage, which is set inside the concrete concealed beam and adapted to its shape and structure; two sets of second reserved reinforcing bars, which are respectively set at both ends of the concealed beam reinforcing cage. Each set of second reserved reinforcing bars includes two reinforcing meshes, which are set opposite to each other on both sides of the concealed beam reinforcing cage. Each reinforcing mesh includes multiple extending horizontal bars, which are spaced apart along the height direction of the concealed beam reinforcing cage. One end of each extending horizontal bar is fixedly connected to the inner side of the concealed beam reinforcing cage, and the other end extends into the corresponding Z-shaped groove along the length direction of the transverse connecting wall. Each extending horizontal bar is fixedly connected by multiple second vertical bars to form a reinforcing mesh.

4. The diaphragm wall foundation retaining structure adjacent to a river channel as described in claim 3, characterized in that, The steel mesh and the adjacent set of first reserved steel bars are respectively arranged on the inner and outer sides of the same side wall of the zigzag groove, and the multiple extended horizontal bars of the steel mesh are arranged in a one-to-one correspondence with the multiple L-shaped horizontal bars of the set of first reserved steel bars.

5. The diaphragm wall foundation retaining structure adjacent to a river channel as described in claim 3, characterized in that, The plurality of first vertical bars are divided into two rows of first vertical bars, which are respectively set on both sides of the horizontal side of the corresponding L-shaped horizontal bar located inside the protrusion. Any row of first vertical bars is spaced apart along the length direction of the corresponding horizontal side, and any first vertical bar is set along the height direction of the concrete hidden beam and fixedly connected to the corresponding plurality of L-shaped horizontal bars. The plurality of second vertical bars are spaced apart along the length of the concrete hidden beam outside the U-shaped groove, and any second vertical bar is arranged along the height of the concrete hidden beam and fixedly connected to the corresponding plurality of extended horizontal bars.

6. The diaphragm wall foundation retaining structure adjacent to a river channel as described in claim 1, characterized in that, The length of the protrusion in the longitudinal direction of the transverse connecting wall is less than or equal to one meter.

7. The diaphragm wall foundation retaining structure adjacent to a river channel as described in claim 1, characterized in that, The basic unit also includes a cap beam, which is correspondingly set on the top of the two wing walls and the transverse diaphragm connecting wall to form an I-shaped beam structure. The cap beam includes two cross beams, which are respectively set on the top of the corresponding two wing walls; and a longitudinal beam, which is set on the top of the corresponding transverse diaphragm connecting wall and connects the two cross beams along its length direction; and multiple cross beams located on the same side of the longitudinal beam in the multiple basic units are sequentially connected along the length direction of the river channel.

8. The diaphragm wall foundation retaining structure adjacent to a river channel as described in claim 7, characterized in that, A concrete tie plate is provided between any two adjacent cap beams, which fills the square cavity formed between the two cap beams and together with the two cap beams forms a supporting plane.

9. A construction method for a diaphragm wall foundation retaining structure adjacent to a river channel as described in any one of claims 1-8, characterized in that, include: S1. Construct the diaphragm walls and guide walls of each foundation unit in the construction area according to the design drawings; S2. Starting with a basic unit, its two wing walls are used as the first construction section, and two trenching machines are used to trench simultaneously. S3. Locking pipe joint boxes are placed at both ends of the groove corresponding to the main body of each wing wall, and a Z-shaped steel plate is placed at the outer end of the groove corresponding to the protrusion of each wing wall as a partition plate for the socket connection structure. The central protrusion of the Z-shaped steel plate is set facing the inner side of the protrusion. The extension plates on both sides of the central protrusion are set parallel to the outer end face of the groove corresponding to the protrusion and abut against its inner side wall. S4. Guided by the lock joint box and the Z-shaped steel plate, lower the wing wall reinforcement cage into the trench section to be constructed first, with the reserved reinforcement extending into the side plate of the Z-shaped steel plate and the inner wall of the trench section corresponding to the protrusion. S5. Using the lock joint box and the Z-shaped steel plate as boundaries, pour the wing wall concrete with slow-setting concrete. S6. After the slow-setting concrete is poured, the transverse diaphragm connecting wall is immediately formed as the subsequent construction section, and the subsequent construction section connects the two previously constructed sections. S7. Using the Z-shaped steel plates located at both ends of the trench section to be constructed later as a guide, the concrete hidden beam reinforcement cage is lowered to a set height position, and the reserved steel bars of the concrete hidden beam reinforcement cage extend into the middle protrusion of the Z-shaped steel plate. S8. Pull up the Z-shaped steel plates at both ends, and simultaneously pour ordinary concrete to build the transverse diaphragm connecting wall concrete as the Z-shaped steel plates are lifted, so that the bottom of the Z-shaped steel plates is within a set distance range above the concrete pouring liquid surface, and pull up the lock joint boxes at both ends simultaneously after a set time. S9. Repeat steps S2-S8 to construct the next adjacent foundation unit until all diaphragm walls are completed. S10. Along the length of the river channel, break down the connecting walls and guide walls in sequence, construct a retaining wall on the top of the wing wall on the side closest to the river channel, and then backfill soil behind the retaining wall to form the ground.

10. The construction method of the diaphragm wall foundation retaining structure adjacent to the river channel as described in claim 9, characterized in that, In S3, after the Z-shaped steel plate is lowered, a protective box is placed in the Z-shaped groove formed by the central protrusion. The protective box is at the same height as the Z-shaped steel plate and its cross-sectional structure is adapted to the Z-shaped groove. In S6, the protective box needs to be pulled out after the transverse connecting wall is grooved.

Images