Fabricated underground diaphragm wall structure and method for constructing underground diaphragm wall using same

Abstract

The invention discloses a fabricated underground diaphragm wall structural body and a construction method of an underground diaphragm wall. The structural body comprises a plurality of member layers along the top and the bottom, the member layers extend in the length direction, and the structural body comprises a top layer and a bottom layer, and the top layer is provided with a plurality of prefabricated concrete members for the fabricated underground diaphragm wall structural body; when N is 1, the N lower layers are located below the top layer and provided with a plurality of prefabricated concrete members for the assembly type underground diaphragm wall structural body, and the number of the prefabricated concrete members corresponds to the number of the corresponding members of the top layer; the adjacent components (1, 1) on the top layer are connected in a concave-convex embedding manner; along the vertical direction, the size of the cross section of the component (1) on the top layer is larger than the corresponding size of the component (7) on the lower layer connected with the component (1); adjacent members (7, 7) in the lower layer are spaced apart in the horizontal direction; angle irons (2, 2) are provided at the corners of one side of the adjacent components of the top layer close to the respective ends which are fitted to each other, and the angle irons (2, 2) are welded at the ends which are fitted to each other.

Description

Technical Field

[0001] This invention relates to the technical field of foundations, and in particular to diaphragm walls. Background Technology

[0002] Jiang Zhengbing of Zhejiang Jitong Dikong Construction Technology Co., Ltd. invented a channel-type cutting prefabricated diaphragm wall and its construction method (see CN201810803258.3). It uses the TRD mixing and implantation process to construct a prefabricated diaphragm wall. The diaphragm wall adopts a prefabricated diaphragm wall structure, which has two layers. Each layer is composed of multiple prefabricated concrete components. The upper layer components are connected to the corresponding lower layer components by welding. The adjacent prefabricated concrete components of the upper layer are connected by mortise and tenon joints. Zhejiang Zhaodi Group Co., Ltd. has further improved the channel-type cutting precast concrete continuous wall technology (see the article "I am Zhaodi Precast Concrete Sheet Pile Continuous Wall, an All-rounder in Underground Green Construction, Good, Fast and Cost-Effective!" published on the WeChat official account: Zhaodi Holding Group on August 17, 2025). That is, the precast concrete components of the upper layer of the precast underground continuous wall structure and the corresponding precast concrete components of the lower layer are connected by screw-lock mechanical connection to replace welding. Rubber strips are added between adjacent precast underground continuous wall sections to achieve water stop. This scheme improves the industrialization level of precast diaphragm walls and enhances their water-stopping performance. However, engineering applications have revealed certain drawbacks. Specifically, during construction, adjacent precast concrete components of the upper-layer precast diaphragm wall structure require mortise and tenon joints for fitting together. This fitting process is cumbersome because the mortise and tenon joints between adjacent upper-layer components have small gaps. If sand or gravel enters the mortise, inserting the tenon becomes extremely difficult, preventing the precast diaphragm wall from being properly installed. Furthermore, the sand and gravel are very difficult to remove from the mortise because the joints between adjacent components in the lower layer also have small gaps. Consequently, once sand or gravel enters the mortise between upper-layer components, it cannot be easily discharged downwards. On the other hand, if the assembly gap between the mortise and tenon joints of two adjacent components in the upper layer is relatively large, the sealing effect will be poor. Relying solely on rubber sheets will not achieve the ideal water-stopping seal. In other words, for current prefabricated diaphragm wall structures, there is a contradiction between water-stopping sealability and assembly performance between adjacent components in the upper layer (first layer) (i.e., either assembly is smooth but water-stopping sealability is poor, or water-stopping sealability is good but assembly is not smooth). Furthermore, the water-stopping mechanism itself has defects; during the assembly and construction of prefabricated diaphragm wall structures, rubber strips are easily damaged or even detached, leading to the failure of the final water-stopping seal in the diaphragm wall. Moreover, once the water-stopping seal fails, repairing it on the inside of the diaphragm wall is extremely difficult. Summary of the Invention

[0003] The purpose of this invention is to provide a prefabricated diaphragm wall structure and a construction method for the diaphragm wall, which can achieve effective and good water-stopping and sealing performance while maintaining the convenience of assembling precast concrete components for the prefabricated diaphragm wall structure.

[0004] To achieve the objectives of this invention, one aspect of this invention provides a prefabricated diaphragm wall structure, which, viewed from above, comprises multiple component layers extending along the length of the prefabricated diaphragm wall structure, and the multiple component layers include: The top floor, which has multiple top-level prefabricated underground continuous wall structures using precast concrete components; There are N lower layers. When N equals 1, the lower layer is located below the top layer. The lower layer has multiple precast concrete components for the prefabricated diaphragm wall structure of the lower layer. The number of precast concrete components for the prefabricated diaphragm wall structure in the lower layer corresponds to the number of precast concrete components for the prefabricated diaphragm wall structure in the top layer. When N is a natural integer other than 1, the N lower layers are located below the top layer as a whole. The N lower layers are stacked on top of each other in the vertical direction and extend parallel to each other in the length direction of the prefabricated diaphragm wall structure. Each of the N lower layers has multiple precast concrete components for the prefabricated diaphragm wall structure of the lower layer. The number of precast concrete components for the prefabricated diaphragm wall structure in each of the N lower layers corresponds to the number of precast concrete components for the prefabricated diaphragm wall structure in the top layer. In the aforementioned top layer, the horizontally adjacent precast concrete components of the precast underground continuous wall structure are connected by a concave-convex interlocking method. When N equals 1, from the top and bottom direction, during construction, among the precast concrete components of the precast underground continuous wall structure in the top layer and the precast concrete components of the precast underground continuous wall structure in the bottom layer, the horizontal cross-sectional dimension of the precast concrete component of the top layer is larger than the horizontal cross-sectional dimension of the precast concrete component of the precast underground continuous wall structure in the bottom layer that is adjacent to it. When N is a natural integer other than 1, from the top and bottom direction, during construction, among the precast concrete components of the precast underground continuous wall structure in the top layer and the precast concrete components of the precast underground continuous wall structure in the N lower layers adjacent to the top layer, the horizontal cross-sectional dimension of the precast concrete component of the precast underground continuous wall structure in the top layer is larger than the horizontal cross-sectional dimension of the precast concrete component of the precast underground continuous wall structure in the lower layer that is connected to it above and below. From the horizontal and longitudinal perspective of the continuous wall structure, the precast concrete components of the multiple precast underground continuous wall structures in the lower layer immediately below the top layer are spaced apart from each other at a predetermined distance. Viewed from the thickness direction of the diaphragm wall structure, angle steel is provided at the corner of at least one side of the precast concrete components of the interlocking adjacent precast diaphragm wall structure in the top layer, near the respective ends of the interlocking components. The angle steel provided at the corner of at least one side of the precast concrete components of the interlocking adjacent precast diaphragm wall structure in the top layer is welded together at the respective ends of the interlocking components to prevent water seepage at the joint between the respective ends of the interlocking components.

[0005] According to the above scheme, in the prefabricated diaphragm wall structure of the present invention, since the horizontal cross-sectional dimension of the prefabricated concrete component of the top layer of the prefabricated diaphragm wall structure is larger than the horizontal cross-sectional dimension of the prefabricated concrete component of the lower layer connected to it, and the horizontally adjacent prefabricated concrete components of the prefabricated diaphragm wall structure in the lower layer immediately below the top layer are spaced apart from each other at a predetermined distance, the sand and gravel that fall into the mortise between the horizontally adjacent prefabricated concrete components of the top layer can easily be discharged from the corresponding horizontally adjacent prefabricated concrete components in the lower layer immediately below the top layer during the component assembly construction. The precast concrete components of the diaphragm wall structure are drained through a relatively large gap, which facilitates the smooth and convenient assembly of horizontally adjacent components. At this time, the joint between adjacent components on the top floor does not need to be too large. Angle steel is provided at the corner of at least one side of the precast concrete components of the precast diaphragm wall structure near the respective ends of the interlocking components on the top floor. It is welded together at the respective ends of the interlocking components to prevent water seepage into the joint between the respective ends of the interlocking components. At this time, the welded angle steel replaces the rubber sheet, which enhances the water-stopping effect. Thus, effective and good water-stopping sealing can be achieved while maintaining the convenience of assembling the precast concrete components of the precast diaphragm wall structure.

[0006] In summary, this invention achieves excellent water-stopping performance by making the horizontal cross-sectional dimension of the components in the top layer larger than the corresponding cross-sectional dimension of the components in the immediately below layer, and by welding angle steel to the corners of the sides of adjacent components in the top layer. This is done by welding angle steel to connect adjacent prefabricated diaphragm wall structures in the top layer using precast concrete components. This ensures that sand and gravel embedded in the joints between adjacent components in the top layer can be smoothly discharged downwards, and that the fitting between adjacent components in the top layer is smooth and quick. Furthermore, it completely seals off groundwater seepage channels. A particularly advantageous feature is that welding defects are easily repaired.

[0007] Preferably, in the above-mentioned prefabricated underground continuous wall structure, the horizontally adjacent prefabricated underground continuous wall structures in the multiple prefabricated concrete components of the top layer are connected by mortise and tenon joints.

[0008] According to the above scheme, the construction is convenient and easy because the mortise and tenon joint is used to connect adjacent components in the top layer.

[0009] Preferably, in any of the above-described prefabricated diaphragm wall structures, the width of the horizontal cross-section of the prefabricated concrete component of the top-level prefabricated diaphragm wall structure (i.e., the thickness of the prefabricated concrete component of the top-level prefabricated diaphragm wall structure) is greater than the width of the horizontal cross-section of the prefabricated concrete component of the lower-level prefabricated diaphragm wall structure connected to it above and below (i.e., the thickness of the prefabricated concrete component of the lower-level prefabricated diaphragm wall structure). Furthermore, the length of the horizontal cross-section of the prefabricated concrete component of the top-level prefabricated diaphragm wall structure (i.e., the length of the prefabricated concrete component of the top-level prefabricated diaphragm wall structure along the overall horizontal longitudinal direction of the prefabricated diaphragm wall structure) is greater than the length of the horizontal cross-section of the prefabricated concrete component of the lower-level prefabricated diaphragm wall structure connected to it above and below (i.e., the length of the prefabricated concrete component of the lower-level prefabricated diaphragm wall structure along the overall horizontal longitudinal direction of the prefabricated diaphragm wall structure).

[0010] According to the above scheme, a variable cross-section design with a larger top and smaller bottom is adopted. Below the concave-convex interlocking parts of the top layer components is a fluid cement-soil mixture. Even if sand and gravel enter the concave-convex interlocking parts during the connection, they will sink into the fluid cement-soil mixture below under their own weight or during the interlocking process, thus ensuring the smooth implementation of the concave-convex interlocking.

[0011] Preferably, in the prefabricated underground continuous wall structure described in any of the above technical solutions, N in the above N lower layers is 1, that is, a total of two lower layers are included.

[0012] According to the above scheme, when the depth of the diaphragm wall is not large, the lower layer is one layer, and together with the top layer, there are a total of two layers, which meets the needs of most construction projects.

[0013] Preferably, in the prefabricated underground continuous wall structure described in any of the above technical solutions, N in the above N lower layers is 2 or 3, that is, a total of two or three lower layers are included.

[0014] According to the above scheme, when the depth of the diaphragm wall is large, the lower layer can be two or three layers, together with the top layer, for a total of three layers, which meets the needs of different construction projects.

[0015] Preferably, in the prefabricated diaphragm wall structure described in any of the above technical solutions, the prefabricated diaphragm wall structure in the top layer, which is connected to the prefabricated diaphragm wall structure in the lower layer by bolts perpendicularly adjacent to it, is connected by prefabricated concrete components.

[0016] According to the above scheme, while improving the industrialization level of prefabricated diaphragm walls, the water-stopping performance of prefabricated diaphragm walls is also improved.

[0017] Preferably, in the prefabricated diaphragm wall structure described in any of the above technical solutions, the prefabricated concrete component of the top layer of the prefabricated diaphragm wall structure is connected to the prefabricated concrete component of the lower layer of the prefabricated diaphragm wall structure perpendicularly adjacent to it by bolts. The top surface of the prefabricated concrete component of the lower layer of the prefabricated diaphragm wall structure is connected to a connecting end plate, the width of which is greater than that of the prefabricated concrete component of the lower layer of the prefabricated diaphragm wall structure, thereby forming a cantilever portion on the top surface of the prefabricated concrete component of the lower layer of the prefabricated diaphragm wall structure. Bolt holes for the bolts to pass through are opened in the cantilever portion. A connecting sleeve is connected to the bottom end of the prefabricated concrete component of the top layer of the prefabricated diaphragm wall structure. One end of the bolt protrudes below the bottom surface of the connecting end plate, and the other end of the bolt passes through the bolt hole opened in the plate and is screwed into the connecting sleeve from bottom to top. An anchoring steel bar is installed at the other end of the connecting sleeve, and the other end of the anchoring steel bar is fixed in the prefabricated concrete component of the top layer of the prefabricated diaphragm wall structure.

[0018] According to the above scheme, the upper and lower components are connected through a joint structure, which includes bolts, connecting end plates and their anchoring steel bars, connecting sleeves and their anchoring steel bars. The operation is not sensitive to the working environment (it can be carried out in rainy weather), the requirements for workers are not high (ordinary workers can operate it), the implementation efficiency is high (simple cleaning, tightening, and then proceeding to the next process), and the quality assurance is easy (few processes). While improving the industrialization level of prefabricated underground continuous walls, it avoids the drawbacks of welding, including: strict requirements for the working environment (it cannot be carried out in rainy weather), high requirements for workers (it is a special operation, only welders can operate it), low implementation efficiency (cleaning, grinding the weld joint, layer welding, inspecting and removing the slag after the inner layer is welded before welding the outer layer, and letting it cool naturally for a few minutes after welding before proceeding to the next process), and difficulty in quality assurance (many processes).

[0019] Preferably, in the prefabricated diaphragm wall structure described in any of the above technical solutions, the prefabricated concrete components used in the top layer and the N lower layers of the prefabricated diaphragm wall structure are reinforced concrete components.

[0020] According to the above plan, a reinforced concrete structure is used, which is low in cost.

[0021] Preferably, in the prefabricated diaphragm wall structure described in any of the above technical solutions, the prefabricated diaphragm wall structure of the top layer and / or the N lower layers uses precast concrete components or reinforced concrete components or prestressed concrete components.

[0022] According to the above scheme, prestressed concrete components are used, which have excellent mechanical properties.

[0023] Another aspect of the present invention is to provide a construction method for a diaphragm wall employing any of the prefabricated diaphragm wall structures described above, characterized in that the method is used when N of the N lower layers is equal to 1, and the method includes: a. To prefabricate and transport multiple precast concrete components for prefabricated underground continuous wall structures in the top layer and multiple precast concrete components for prefabricated underground continuous wall structures in the lower layer, wherein during the prefabrication of the multiple precast concrete components for prefabricated underground continuous wall structures in the top layer, angle steel is provided at the corner of at least one side of the mutually interlocking adjacent precast concrete components for prefabricated underground continuous wall structures in the top layer, near the respective ends of the mutually interlocking components. b. On-site construction of cement-soil mixing walls; c. Before the cement-soil mixing wall is in a fluid state, allowing precast concrete components of the lower layer's prefabricated diaphragm wall structure to be inserted into the cement-soil mixing wall and placed at the designed position and elevation, the precast concrete components of the lower layer's prefabricated diaphragm wall structure are initially inserted into the cement-soil mixing wall formed by step b, with adjacent precast concrete components of the lower layer spaced apart by a predetermined interval. The precast concrete components of the upper layer's prefabricated diaphragm wall structure are then connected to the precast concrete components of the lower layer's prefabricated diaphragm wall structure that have been initially inserted. d. In order to facilitate the welding of the joints between adjacent angle steels to be welded together, the soil around the aforementioned angle steels is removed, and the adjacent prefabricated diaphragm wall structures in the aforementioned top layer are welded together at the corners of the prefabricated concrete components near their respective interlocking ends along at least one side of the horizontal longitudinal direction of the entire prefabricated diaphragm wall structure to prevent water leakage at the joints at the ends.

[0024] According to the above technical solution, effective and good water-stopping performance can be achieved while maintaining the convenience of assembling precast concrete components for prefabricated underground continuous wall structures. Specifically, a variable cross-section design with a larger upper section and a smaller lower section is adopted. The components of the lower layer are spaced apart, and the spaces between the components are filled with a fluid cement-soil mixture. Above this cement-soil mixture is the extension of the upper layer components beyond the components of the lower layer, which includes interlocking parts. Below the interlocking parts of the upper layer components is the fluid cement-soil mixture. Even if sand or gravel enters the interlocking parts during the interlocking connection, it will sink into the fluid cement-soil mixture below under its own weight or during the interlocking process, thus ensuring the smooth implementation of the interlocking. While ensuring the smooth interlocking between adjacent components in the upper layer, the adjacent precast concrete components of the prefabricated underground continuous wall structure in the upper layer are connected into one unit by welding angle steel, completely sealing the groundwater infiltration channels and achieving excellent water-stopping and sealing performance. Particularly advantageous is that welding quality defects are easy to repair.

[0025] Preferably, in any of the above-described construction methods, before the initial setting of the cement-soil mixing wall, step c is performed as follows: a precast concrete component of the first lower layer prefabricated diaphragm wall structure is inserted into the cement-soil mixing wall; a precast concrete component of the top layer prefabricated diaphragm wall structure, which is connected to the precast concrete component of the first lower layer prefabricated diaphragm wall structure, is connected to the precast concrete component of the first lower layer prefabricated diaphragm wall structure already inserted into the cement-soil mixing wall; and then, the process continues. In the cement-soil mixing wall, this process continues until the design elevation is reached. Then, the last prefabricated concrete component of the prefabricated underground continuous wall structure in the last lower layer is placed in the cement-soil mixing wall. At the design elevation, the last prefabricated concrete component of the top layer, which is connected to the prefabricated concrete component of the prefabricated underground continuous wall structure in the last lower layer, is connected to the prefabricated concrete component of the prefabricated underground continuous wall structure in the last lower layer that has been implanted in the cement-soil mixing wall. This process continues until the design elevation is reached.

[0026] According to the above technical solution, through implantation, connection and implantation, the precast concrete components of the top-level prefabricated underground continuous wall structure are connected to the corresponding precast concrete components of the lower-level prefabricated underground continuous wall structure to form a whole, and placed at the designed position and elevation.

[0027] Preferably, in the above construction method, before the initial setting of the cement-soil mixing wall, step c is carried out in the following manner: multiple prefabricated concrete components of the prefabricated underground continuous wall structure in the lower layer are placed one by one into the cement-soil mixing wall to the design elevation; then, multiple prefabricated concrete components of the prefabricated underground continuous wall structure in the top layer are connected one by one to the prefabricated concrete components of the prefabricated underground continuous wall structure in the lower layer that have been set up.

[0028] According to the plan, the prefabricated underground continuous wall structure in the lower layer is placed in the design position using precast concrete components through implantation and connection. The prefabricated underground continuous wall structure in the top layer is connected to it with precast concrete components to form an integral whole, which prepares for placing the connected whole in the design position and elevation.

[0029] Preferably, in any of the above-described construction methods, steps a and b are performed in the manner described above, wherein step a is performed first, followed by step b.

[0030] Preferably, in any of the above-described construction methods, steps a and b are performed in such a manner as follows: step b is performed first, followed by step a.

[0031] Preferably, in any of the above-described construction methods, steps a and b are performed in such a way that steps b and a are performed simultaneously.

[0032] Preferably, in any of the above-described construction methods, step d is performed in the following manner: in the joints formed between the ends of the precast concrete components of the multiple precast diaphragm wall structures in the top layer, angle steels provided at the corners of one side of adjacent precast concrete components of the precast diaphragm wall structures in the top layer near their respective interlocking ends are welded together at their respective interlocking ends to prevent water leakage at the joints.

[0033] According to the above technical solution, adjacent prefabricated underground continuous wall structures in the top floor are connected as a whole using precast concrete components through angle steel welding, completely sealing off the groundwater seepage channels. A particularly advantageous feature is that any welding quality defects are easy to repair.

[0034] Preferably, in any of the above-described construction methods, step d is performed in the following manner: for the joints formed between the ends of the precast concrete components of the multiple prefabricated underground continuous wall structures in the top layer, simultaneously for all joints, angle steels provided at the corners of the adjacent prefabricated concrete components of the prefabricated underground continuous wall structures near their respective interlocking ends are welded together at their respective interlocking ends to prevent water leakage at the end joints.

[0035] According to the above technical solution, adjacent prefabricated underground continuous wall structures in the top floor are connected as a whole using precast concrete components through angle steel welding, completely sealing off the groundwater seepage channels. A particularly advantageous feature is that any welding quality defects are easy to repair.

[0036] Preferably, in any of the above-described construction methods, step d is performed in the following manner: in the joints formed between the ends of the precast concrete components of the plurality of prefabricated underground continuous wall structures in the top layer, simultaneously for a portion of the joints, angle steels provided at the corners of one side of the adjacent precast concrete components of the prefabricated underground continuous wall structures near their respective interlocking ends are welded together at their respective interlocking ends to prevent water leakage at the end joints.

[0037] According to the above technical solution, adjacent prefabricated underground continuous wall structures in the top floor are connected as a whole using precast concrete components through angle steel welding, completely sealing off the groundwater seepage channels. A particularly advantageous feature is that any welding quality defects are easy to repair.

[0038] Preferably, in any of the above-described construction methods, the connection between the precast concrete components of the top-level prefabricated diaphragm wall structure and the precast concrete components of the lower-level prefabricated diaphragm wall structure that have been preliminarily installed is achieved by bolts.

[0039] According to the above technical solution, the upper and lower components are connected by bolts, which improves the industrialization level of the prefabricated diaphragm wall and improves the water-stopping performance of the prefabricated diaphragm wall. Attached Figure Description

[0040] Figure 1 This is a partial vertical sectional view of a prefabricated underground continuous wall structure, which is an embodiment of the present invention. Figure 2 To indicate along Figure 1 A vertical sectional view along line 1-1 in a portion of the prefabricated underground continuous wall structure shown; Figure 3 To indicate along Figure 1A horizontal sectional view along line 2-2 in a portion of the top layer of the prefabricated underground continuous wall structure shown; Figure 4 To indicate along Figure 1 A horizontal sectional view along line 3-3 in a portion of the prefabricated underground continuous wall structure shown. Figure 5 To indicate along Figure 1 A horizontal sectional view along line 4-4 in a partial section of the bottom layer of the prefabricated underground continuous wall structure shown. Figure 6 This is a schematic diagram illustrating the step of prefabricating and transporting components in a prefabricated diaphragm wall structure in a construction method for a diaphragm wall, which is an embodiment of the present invention. Figure 7 This is a schematic diagram illustrating the steps of constructing a cement-soil mixing wall on-site in a method for constructing a diaphragm wall, which is an embodiment of the present invention. Figure 8 To illustrate the step in the construction method of the underground continuous wall as an embodiment of the present invention, which involves initially embedding the first bottom layer of the prefabricated underground continuous wall structure into the above-mentioned cement-soil mixing wall using precast concrete components. Figure 9 To illustrate the step of applying grout or epoxy resin to the top surface of a precast concrete component of the prefabricated diaphragm wall structure that is initially implanted in the first layer of the diaphragm wall construction method, which is an embodiment of the present invention. Figure 10 To illustrate the step in the construction method of a diaphragm wall as an embodiment of the present invention, the first top-level prefabricated concrete component of the prefabricated diaphragm wall structure is placed on the top surface of the initially implanted bottom-level prefabricated concrete component of the diaphragm wall structure and connected thereto. Figure 11 To illustrate the step in the construction method of the diaphragm wall as an embodiment of the present invention, the precast concrete components of the first top-level precast diaphragm wall structure and the precast concrete components of the first bottom-level precast diaphragm wall structure are inserted into the above-mentioned cement-soil mixing wall until the design elevation is reached. Figure 12 To illustrate the step of initially embedding the second bottom layer of the prefabricated diaphragm wall structure into the above-mentioned cement-soil mixing wall in the construction method of the diaphragm wall as an embodiment of the present invention. Figure 13 To illustrate the step of applying grout or epoxy resin to the top surface of a precast concrete component of the prefabricated diaphragm wall structure that is initially implanted as an embodiment of the present invention in the construction method of the diaphragm wall. Figure 14To illustrate the step in the construction method of a diaphragm wall as an embodiment of the present invention, the precast concrete component of the second top-level precast diaphragm wall structure is placed on the top surface of the precast concrete component of the initially implanted bottom-level precast diaphragm wall structure and connected thereto. Figure 15 To illustrate the step in the construction method of the diaphragm wall as an embodiment of the present invention, the precast concrete components of the precast diaphragm wall structure of the second top layer and the precast concrete components of the precast diaphragm wall structure of the second bottom layer are inserted into the above-mentioned cement-soil mixing wall until the design elevation is reached. Figure 16 This is a schematic diagram illustrating the steps of sequentially implanting and connecting precast concrete components of other bottom-layer precast diaphragm wall structures and corresponding top-layer precast diaphragm wall structures in a construction method for a diaphragm wall, as an embodiment of the present invention. Figure 17 This is a schematic diagram illustrating the step of excavating earthwork in the foundation pit for the diaphragm wall in a construction method for a diaphragm wall, which is an embodiment of the present invention. Figure 18 This is a schematic diagram illustrating the angle steel welding step in the construction method of a diaphragm wall as an embodiment of the present invention.

[0041] Description of specific embodiments The following is combined Figures 1-5 The prefabricated underground continuous wall structure, which is an embodiment of the present invention, will be described in detail.

[0042] Figure 1 To show a partial vertical sectional view of the prefabricated underground continuous wall structure as an embodiment of the present invention, as shown below. Figure 1 As shown, in the prefabricated diaphragm wall structure, which is an embodiment of the present invention, multiple top-level prefabricated concrete components 1 and multiple bottom-level prefabricated concrete components 7 are provided when viewed from the top and bottom directions. Here, the prefabricated diaphragm wall structure includes a top level and a bottom level, totaling two levels.

[0043] The precast concrete components 1 of the precast concrete components 1 of the precast underground continuous wall structure of the above-mentioned multiple top-level precast underground continuous wall structures are connected to each other in a concave-convex interlocking manner, which facilitates construction.

[0044] Viewed from above and below, in the aforementioned precast concrete components 1 of the multiple top-level precast diaphragm wall structures and the aforementioned precast concrete components 7 of the multiple bottom-level precast diaphragm wall structures, the horizontal cross-sectional dimension of the top-level precast concrete component 1 is larger than the horizontal cross-sectional dimension of the adjacent bottom-level precast concrete component 7, adopting a variable cross-section design with a larger top and smaller bottom. Below the concave-convex interlocking part of the top-level component is a fluid cement-soil mixture. Even if sand or gravel enters the concave-convex interlocking part during the connection, it will sink into the fluid cement-soil mixture below under its own weight or during the interlocking process, thus ensuring the smooth implementation of the concave-convex interlocking connection.

[0045] Viewed horizontally and longitudinally from the perspective of the continuous wall structure, the precast concrete components 7 of the multiple bottom-level precast underground continuous wall structures are horizontally adjacent, spaced apart by a predetermined interval. The bottom-level components are also spaced apart, filling the spaces between them with a fluid cement-soil mixture. Above this cement-soil mixture is the extension of the top-level components beyond the bottom-level components, which includes a concave-convex interlocking part. Even if sand or gravel enters the concave-convex interlocking part during the connection, it will sink into the fluid cement-soil mixture below under its own weight or during the interlocking process, thus ensuring the smooth implementation of the concave-convex interlocking connection.

[0046] An angle steel 2 is provided at the corner of one side of the precast concrete component 1, 1 ...

[0047] Figure 2 To indicate along Figure 1 The vertical sectional view along line 1-1 in a portion of the prefabricated diaphragm wall structure shown here... Figure 2 This is a sectional view along the thickness direction of the prefabricated diaphragm wall structure, such as... Figure 1 and Figure 2As shown, the prefabricated diaphragm wall structure includes a top layer and a bottom layer. The top layer is composed of multiple prefabricated concrete components 1, and the bottom layer is composed of multiple prefabricated concrete components 7. Viewed from above and below, in... Figure 2 A set of components is shown, comprising a precast concrete component 1 for a top-level precast diaphragm wall structure and a precast concrete component 7 for a bottom-level precast diaphragm wall structure, constituting... Figure 2 The precast concrete component 1 of the top-level precast diaphragm wall structure and the precast concrete component 7 of the bottom-level precast diaphragm wall structure shown in the diagram are connected to each other in the vertical direction with their respective vertical center aligned. In this group of components, a connecting end plate 9 is provided on the top of the bottom-level precast concrete component 7, and a stiffening plate 16 is fixed on the bottom surface of the connecting end plate 9. Figure 4 As shown, this will be described later. The stiffening plate 16 is fixed to the concrete body of the precast concrete component 7 of the underlying prefabricated diaphragm wall structure by welding to the anchor bars 6, as... Figure 2 As shown. A connecting sleeve 4 is installed at the bottom of the precast concrete component 1 of the top-floor prefabricated underground continuous wall structure. It is fixed to the concrete body of the precast concrete component 1 of the top-floor prefabricated underground continuous wall structure by welding or threading with the anchor bars 3, as shown. Figure 2 As shown. Connecting bolt holes 5 are made on the connecting end plate 9, as follows. Figure 4 As shown, this point will be described later. The bolt passes through the connecting bolt hole 5 from bottom to top and is screwed into the connecting sleeve 4. Then, a nut 8 is installed on the lower end of the bolt under the connecting end plate 9 and tightened, thereby locking the connecting end plate 9 and the connecting sleeve 4 together. In this way, the precast concrete component 1 of the top-level prefabricated diaphragm wall structure and the precast concrete component 7 of the bottom-level prefabricated diaphragm wall structure are firmly connected.

[0048] Figure 3 To indicate along Figure 1 The horizontal sectional view along line 2-2 in a portion of the top layer of the prefabricated underground continuous wall structure, which is an embodiment of the present invention, is shown below. Figure 3 As shown, this section represents a portion of the upper layer of a prefabricated diaphragm wall structure, which is an embodiment of the present invention. The lower layer of the prefabricated diaphragm wall structure, as an embodiment of the present invention, is composed of multiple upper-layer prefabricated diaphragm wall structures made of precast concrete components 1. Figure 3In the diagram, two precast concrete components 1,1 of the top-level prefabricated diaphragm wall structure are observed. These two components 1,1 are adjacent to each other and joined by mortise and tenon joints. The left component 1 has a mortise groove 12, and the right component 1 has a tenon 10. The tenon 10 of the right component 1 engages with the mortise groove 12 of the left component 1 to achieve connection. Angle steel 2 is provided at the corners of the lower side 13 of each component 1, i.e., at both ends of the side 13. Here, the top-level prefabricated diaphragm wall structure has two sides in the horizontal longitudinal direction. Figure 3 The top side 11 and Figure 3 The lower side 13, the aforementioned side 11 is the side of the precast concrete component 1 of the top-level prefabricated underground continuous wall structure that is away from the foundation pit of the basement. This side 13 is, for example, the foundation pit of the basement (not shown in the figure). Near each angle steel 2 inside the concrete of the precast concrete component 1 of the top-level prefabricated underground continuous wall structure, there are 2 anchor bars 14. The angle steel 2 and the anchor bars 14 are welded together. At the bottom end of each precast concrete component 1 of the top-level prefabricated underground continuous wall structure, there are 2 rows of connecting sleeves, with 4 connecting sleeves 4 in each row, for a total of 8 connecting sleeves 4.

[0049] Figure 4 To indicate along Figure 1 The horizontal sectional view along line 3-3 in a portion of the prefabricated underground continuous wall structure, which is an embodiment of the present invention, is shown below. Figure 4 As shown, it can be seen that, as an embodiment of the present invention, there are two connecting end plates 9, 9 on the top surface of the precast concrete components 7 of the precast underground continuous wall structure located at the bottom layer. Stiffening plates 16, 16 perpendicular to each other are provided on the upper surface of each connecting end plate 9. Two rows of connecting bolt holes are provided in each connecting end plate 9, and each row of connecting bolt holes includes 4 connecting bolt holes 5.

[0050] Figure 5 To indicate along Figure 1 The horizontal sectional view along line 4-4 of the bottom layer of the prefabricated underground continuous wall structure, which is an embodiment of the present invention, is shown below. Figure 5As shown, this section represents a portion of the bottom layer of a prefabricated diaphragm wall structure, which is an embodiment of the present invention. The bottom layer of the prefabricated diaphragm wall structure, as an embodiment of the present invention, is composed of multiple bottom layers of prefabricated diaphragm wall structures using precast concrete components 7. Figure 5 In the middle, we see two precast concrete components 7,7 of the bottom layer of the precast underground continuous wall structure. These two precast concrete components 7,7 of the bottom layer of the precast underground continuous wall structure are adjacent to each other but separated by a certain distance.

[0051] The following is combined Figures 6 to 18 The construction method of the diaphragm wall, which is an embodiment of the present invention, will be described in detail.

[0052] First, proceed to step 1. Regarding step 1, Figure 6 This diagram illustrates the step of prefabricating and transporting components in a prefabricated diaphragm wall structure in a construction method for a diaphragm wall, as an embodiment of the present invention. Specifically, in the first step of the construction method for a diaphragm wall, as an embodiment of the present invention, reference numeral 17 represents the natural ground surface, such as... Figure 7 As shown, precast concrete components are used for both the bottom and top precast diaphragm wall structures. For example, these components are precast in a factory and then transported to the construction site. Here, for example, regarding... Figure 6 The prefabrication process only shows a portion of the prefabricated concrete components 7 for the bottom layer of the prefabricated diaphragm wall structure and a portion of the prefabricated concrete components 1 for the top layer of the prefabricated diaphragm wall structure. In this prefabrication process, two prefabricated concrete components 1 for the top layer of the prefabricated diaphragm wall structure are prefabricated. During the prefabrication of the prefabricated concrete components 1 for the prefabricated diaphragm wall structure, angle steel 2 is welded to both ends of each top layer prefabricated concrete component 1 near the corner of the component, i.e., the inner corner of the foundation pit. Figure 3 As shown, a connecting sleeve 4 is embedded at the bottom end of the precast concrete component 1 of the top-level prefabricated underground continuous wall structure; in addition, two precast concrete components 7, 7 of the bottom-level prefabricated underground continuous wall structure are prefabricated, and a connecting end plate 9 is fixed on the top surface of the precast concrete component 7 of the bottom-level prefabricated underground continuous wall structure.

[0053] Next, proceed to step 2. Regarding step 2, Figure 7 This is a schematic diagram illustrating the steps of constructing a cement-soil mixing wall on-site in a method for constructing a diaphragm wall, as an embodiment of the present invention. Specifically, in the second step of the method for constructing a diaphragm wall, as an embodiment of the present invention, reference numeral 17 represents the natural ground surface, such as... Figure 7As shown, at the construction site of the diaphragm wall, cement-soil mixing wall is constructed to form cement-soil mixing wall 15. The cement-soil mixing wall is fluid before initial setting, which allows the precast concrete components of the bottom prefabricated diaphragm wall structure to be inserted into it and placed at the designed position and elevation.

[0054] Then, proceed to step 3. Regarding step 3... Figure 8 To illustrate the step of initially embedding the first layer of prefabricated diaphragm wall structure into the cement-soil mixing wall using precast concrete components in the diaphragm wall construction method according to an embodiment of the present invention, in this state, reference numeral 17 indicates the natural ground surface. Specifically, in the third step of the diaphragm wall construction method according to an embodiment of the present invention, as follows... Figure 8 As shown, in the formed cement-soil mixing wall 15, a precast concrete component 7 for the bottom layer of the prefabricated diaphragm wall structure is initially inserted. At this position, the top of the precast concrete component 7 for the bottom layer of the prefabricated diaphragm wall structure protrudes from the top surface of the cement-soil mixing wall 15. The aforementioned precast concrete component 7 for the bottom layer of the prefabricated diaphragm wall structure is prefabricated, and a connecting end plate 9 is fixed to its top. A stiffening plate 16 is fixed to the bottom surface of the connecting end plate 9. The stiffening plate 16 is fixed to the concrete body of the precast concrete component 7 for the bottom layer of the prefabricated diaphragm wall structure by welding with multiple anchor bars 6. The insertion of the precast concrete component 7 for the bottom layer of the prefabricated diaphragm wall structure into the cement-soil mixing wall must be completed before the initial setting of the cement-soil mixing wall. Through insertion, the first precast concrete component for the bottom layer of the prefabricated diaphragm wall structure is placed in the designed position, preparing for the connection of the precast concrete component for the top layer of the prefabricated diaphragm wall structure to form a whole.

[0055] Next, proceed to step 4. Regarding step 4... Figure 9 To illustrate the step of applying grout or epoxy resin to the top surface of the precast concrete component of the first prefabricated diaphragm wall structure, which is initially implanted in the construction method of the diaphragm wall according to an embodiment of the present invention, specifically, the fourth step of the construction method of the diaphragm wall according to an embodiment of the present invention, as follows: Figure 9 As shown, grout or epoxy resin is applied to the connecting end plate 9 fixed on the top surface of the first precast concrete component 7 of the prefabricated underground continuous wall structure, which was initially implanted in step 4. By applying grout or epoxy resin to the top surface, it can be ensured that the precast concrete component of the prefabricated underground continuous wall structure at the bottom layer is in close contact with the precast concrete component of the prefabricated underground continuous wall structure at the top layer, without leaving gaps, thereby reliably connecting the upper and lower components into a whole.

[0056] Next, proceed to step 5. Regarding step 5, Figure 10 To illustrate the step in the construction method of a diaphragm wall according to an embodiment of the present invention, where a precast concrete component of the first top-level precast diaphragm wall structure is placed on the top surface of the initially implanted bottom-level precast concrete component of the precast diaphragm wall structure and aligned with it for connection, in this state, reference numeral 17 indicates the natural ground surface. Specifically, in the fifth step of the construction method of a diaphragm wall according to an embodiment of the present invention, as follows... Figure 10 As shown, the first top-level precast concrete component 1 of the prefabricated diaphragm wall structure is placed on top of the initially implanted bottom-level prefabricated concrete component 7. Bolts are passed through the connecting bolt holes 5 from bottom to top and screwed into the connecting sleeve 4. Nuts 8 are then installed on the lower end of the bolts under the connecting end plate 9 and tightened, thereby locking the connecting end plate 9 and the connecting sleeve 4 together. The first bottom-level prefabricated concrete component of the prefabricated diaphragm wall structure is connected to the top-level prefabricated concrete component of the prefabricated diaphragm wall structure to form a whole, which can then be implanted together and ultimately bear the load together.

[0057] Then, proceed to step 6. Regarding step 6, Figure 11 To illustrate the step of embedding the first set of components into the aforementioned cement-soil mixing wall in the construction method of the diaphragm wall as an embodiment of the present invention, up to the design elevation, specifically, the sixth step of the construction method of the diaphragm wall as an embodiment of the present invention, as follows: Figure 11 As shown, the first set of components, namely, the precast concrete component 1 of the first top-level precast diaphragm wall structure and the precast concrete component 7 of the first bottom-level precast diaphragm wall structure, are further inserted into the aforementioned cement-soil mixing wall 15 until the design elevation is reached. The connection between the top-level precast concrete component and the corresponding bottom-level precast concrete component already inserted into the cement-soil mixing wall must be completed before the cement-soil mixing wall initially sets. After this step, the first bottom-level precast concrete component and the top-level precast concrete component are placed as a whole at the design position and elevation.

[0058] Next, proceed to step 7. Regarding step 7, Figure 12To illustrate the step of initially embedding the precast concrete component of the second bottom layer of the prefabricated diaphragm wall structure into the cement-soil mixing wall in the construction method of the diaphragm wall as an embodiment of the present invention, in this state, the first group of components (consisting of the precast concrete component 7 of the first bottom layer of the prefabricated diaphragm wall structure and the precast concrete component 1 of the top layer of the prefabricated diaphragm wall structure) has been connected, wherein reference numeral 17 indicates the natural ground surface. Specifically, in the seventh step of the construction method of the diaphragm wall as an embodiment of the present invention, as follows... Figure 12 As shown, the second bottom-layer precast concrete component 7 of the prefabricated diaphragm wall structure is initially inserted into the aforementioned cement-soil mixing wall 15, positioning it in this initial location for connection with the top-layer prefabricated concrete component 1 of the prefabricated diaphragm wall structure. The insertion of the bottom-layer prefabricated concrete component into the cement-soil mixing wall must be completed before the cement-soil mixing wall initially sets. Through this insertion, the second bottom-layer prefabricated concrete component of the prefabricated diaphragm wall structure is placed in its designed position, preparing for connection with the top-layer prefabricated concrete component of the prefabricated diaphragm wall structure to form a unified whole.

[0059] Next, proceed to step 8. Regarding step 8, Figure 13 To illustrate the step of applying grout or epoxy resin to the top surface of the precast concrete component of the prefabricated diaphragm wall structure used in the construction method of the diaphragm wall as an embodiment of the present invention, in this state, the first group of components has been connected, that is, the top prefabricated concrete component 1 of the prefabricated diaphragm wall structure used in the prefabricated diaphragm wall structure. Figure 14 The left-hand component 1) has been connected to the precast concrete component 7 of the bottom-level prefabricated underground continuous wall structure. Figure 14 The left-hand component 7) is connected, and the first group of components has been further embedded into the cement-soil mixing wall 15 until the design elevation, where reference numeral 17 indicates the natural ground level. Specifically, the eighth step of the construction method for the diaphragm wall, as an embodiment of the present invention, is as follows: Figure 13 As shown, grouting material or epoxy resin is applied to the upper surface of the connecting end plate 9 on the top surface of the precast concrete component 7 of the precast underground continuous wall structure in the bottom layer initially embedded in the cement-soil mixing wall 15. By applying grouting material or epoxy resin to the top surface, it can be ensured that the precast concrete component 7 of the precast underground continuous wall structure in the bottom layer and the precast concrete component 1 of the precast underground continuous wall structure in the top layer are in close contact without gaps, thereby reliably connecting the upper and lower components into a whole.

[0060] Then, proceed to step 9. Regarding step 9... Figure 14 To illustrate the step in the construction method of a diaphragm wall as an embodiment of the present invention, where a precast concrete component for a second top-level precast diaphragm wall structure is placed on the top surface of a precast concrete component for a bottom-level precast diaphragm wall structure that has been initially implanted, and aligned and connected with it, in this state, the first group of components has been connected, that is, the top-level precast concrete component 1 for a precast diaphragm wall structure in the precast diaphragm wall structure used in the diaphragm wall ( Figure 14 The left-hand component 1) has been connected to the precast concrete component 7 of the bottom-level prefabricated underground continuous wall structure. Figure 14 The left-hand component 7) is connected, and the first group of components has been further embedded into the cement-soil mixing wall 15 until the design elevation, where reference numeral 17 indicates the natural ground level. Specifically, in the ninth step of the construction method of the diaphragm wall as an embodiment of the present invention, as follows... Figure 14 As shown, the second group of components is connected, that is, the top layer of the prefabricated diaphragm wall structure in the prefabricated diaphragm wall structure used in the diaphragm wall is connected using precast concrete component 1 ( Figure 14 The component 1 on the right side of the middle section and the precast concrete component 7 of the bottom layer of the prefabricated underground continuous wall structure. Figure 14 The component 7 on the right side of the structure is connected by bolts passing through the connecting bolt hole 5 from bottom to top and screwing them into the connecting sleeve 4. Then, nuts 8 are installed on the lower end of the bolts under the connecting end plate 9 and tightened, thereby locking the connecting end plate 9 and the connecting sleeve 4 together. The second bottom-layer prefabricated diaphragm wall structure uses precast concrete components, which are then connected to the top-layer prefabricated diaphragm wall structure to form a whole. They can then be installed together and ultimately bear the load together.

[0061] Next, proceed to step 10. Regarding step 10... Figure 15 To illustrate the step in the construction method of a diaphragm wall according to an embodiment of the present invention, where the precast concrete component 1 of the connected second top-level precast diaphragm wall structure and the precast concrete component 7 of the second bottom-level precast diaphragm wall structure are further inserted into the aforementioned cement-soil mixing wall until the design elevation is reached, specifically, in the 10th step of the construction method of a diaphragm wall according to an embodiment of the present invention, as follows... Figure 15As shown, the second set of components, namely, the connected second top-level precast concrete component 1 and the second bottom-level precast concrete component 7, are inserted into the cement-soil mixing wall 15 by inserting the tenon 10 at the end of one of the two adjacent top-level precast concrete components 1 into the mortise 12 at the end of the other top-level precast concrete component 1, until the design elevation is reached. Figure 15 At the end of this step, the precast concrete components 7, 7 of the horizontally adjacent precast diaphragm wall structure in the bottom layer are spaced apart by a predetermined interval, with the wall material of the cement-soil mixing wall 15 in between. Here, reference numeral 17 indicates the natural ground level. The precast concrete component 1 of the precast diaphragm wall structure in the top layer is connected to the corresponding precast concrete component 7 of the precast diaphragm wall structure in the bottom layer, which has been embedded in the cement-soil mixing wall, and then implanted into the cement-soil mixing wall 15. This must be completed before the cement-soil mixing wall initially sets. After this step, the precast concrete component of the precast diaphragm wall structure in the second bottom layer, together with the precast concrete component of the precast diaphragm wall structure in the top layer, is placed as a whole at the designed position and elevation.

[0062] Next, proceed to step 11. Regarding step 11, Figure 16 This diagram illustrates the steps of sequentially inserting and connecting precast concrete components 7 for other precast diaphragm wall structures at the bottom layer and corresponding precast concrete components 1 for the precast diaphragm wall structures at the top layer in a diaphragm wall construction method according to an embodiment of the present invention. Specifically, step 11 of the diaphragm wall construction method according to an embodiment of the present invention is as follows: Figure 16 As shown, in Figure 15 At the end of the steps, the two sets of components in the middle (each set consisting of the corresponding precast concrete component 1 for the top-level precast diaphragm wall structure and the corresponding precast concrete component 7 for the bottom-level precast diaphragm wall structure) have been completely installed at the design elevation. In this state, the precast concrete component 1 for the top-level precast diaphragm wall structure used in the diaphragm wall has been connected to the precast concrete component 7 for the bottom-level precast diaphragm wall structure. The horizontally adjacent precast concrete components 7 for the bottom-level precast diaphragm wall structure are spaced apart by a predetermined interval, with the wall material of the cement-soil mixing wall 15 in between. Here, the reference numeral 17 indicates the natural ground level. Figure 15 After the steps are completed, for Figure 15The two sets of components shown are accompanied by one corresponding set of components on the left and right sides (each set consists of a precast concrete component 1 for the precast underground continuous wall structure in the corresponding top layer and a precast concrete component 7 for the precast underground continuous wall structure in the corresponding bottom layer), that is, a total of two sets of components are arranged according to... Figures 12-15 The steps include the initial implantation of precast concrete components 7 for the bottom-level prefabricated diaphragm wall structure, the connection of precast concrete components 1 for the top-level prefabricated diaphragm wall structure located above it, and the further implantation of this group of components to the design elevation. Figures 12-15 The steps for each of the other groups of components (each group consists of the corresponding top-level precast concrete component 1 and the corresponding bottom-level precast concrete component 7) are as follows: initial implantation of the bottom-level precast concrete component 7, connection of the top-level precast concrete component 1 above it, and further implantation of the group of components to the design elevation, until all groups of components are finally implanted to the design elevation, thus initially completing the overall formation of the precast diaphragm wall structure (except for the corresponding angle steels not being welded together). The implantation of the bottom-level precast concrete component 7 into the cement-soil mixing wall 15, and the connection of the top-level precast concrete component 1 with the corresponding bottom-level precast concrete component 7 already implanted in the cement-soil mixing wall 15, must all be completed before the initial setting of the cement-soil mixing wall. After this step, all the precast concrete components 7 of the bottom layer of the prefabricated underground continuous wall structure are placed together with the corresponding precast concrete components 1 of the top layer of the prefabricated underground continuous wall structure at the designed position and elevation.

[0063] Then, proceed to step 12. Regarding step 12, Figure 17This diagram illustrates the excavation step within the foundation pit for the diaphragm wall in the construction method of the diaphragm wall as an embodiment of the present invention. In this state, the precast concrete components 1 of the top-level precast diaphragm wall structure used for the diaphragm wall have been connected to the precast concrete components 7 of the bottom-level precast diaphragm wall structure located below them. The horizontally adjacent precast concrete components 7, 7 of the bottom-level precast diaphragm wall structure are spaced apart by a predetermined interval, with the wall material of the cement-soil mixing wall 15 in between. Here, reference numeral 17 indicates the natural ground surface, and reference numeral 19 indicates the bottom of the foundation pit for the basement. Along the horizontal direction of the diaphragm wall, a capping beam 18 connecting the top surfaces of the multiple components 1, 1 is cast on the top-level precast concrete components 1, 1 of the precast diaphragm wall structure used for the diaphragm wall. Specifically, in the 12th step of the construction method of the diaphragm wall as an embodiment of the present invention, as follows... Figure 17 As shown, along the horizontal side of the diaphragm wall, on the side of the diaphragm wall near the foundation pit, the excavation is carried out in the foundation pit on the side of the precast concrete component 1 of the top precast diaphragm wall structure of the diaphragm wall structure. The excavation proceeds downward from the capping beam 18 below the elevation of the natural ground 17, that is, from the top of the angle steel 2 in the precast concrete component 1 of the top precast diaphragm wall structure, until the bottom 19 of the foundation pit for the basement is reached. This exposes the corresponding angle steel 2,2 that will be welded immediately. This step is a preparation step for step 13 below, that is, welding the corresponding angle steel. As a result, the excavation of the foundation pit can be carried out safely under the protection of the diaphragm wall.

[0064] Next, proceed to step 13. Regarding step 13... Figure 18 This is a schematic diagram illustrating the angle steel welding step in the construction method of a diaphragm wall as an embodiment of the present invention. Figure 18 As shown, in the prefabricated concrete components 1 of the top-level prefabricated diaphragm wall structure used in the diaphragm wall, the components 7 of the bottom-level prefabricated diaphragm wall structure have been connected. The horizontally adjacent prefabricated concrete components 7 of the bottom-level diaphragm wall structure are spaced apart by a predetermined interval, with a cement-soil mixing wall 15 in between. Here, reference numeral 17 indicates the natural ground surface, and reference numeral 19 indicates the bottom of the foundation pit for the basement. Specifically, in step 13 of the diaphragm wall construction method according to an embodiment of the present invention, as follows... Figure 18As shown, in the prefabricated diaphragm wall structure used as an embodiment of the present invention, the horizontally adjacent prefabricated diaphragm wall structures at the top level are welded together with corresponding angle steels 2, 2 from precast concrete components 1, 1 to form weld seams 20. By welding the exposed adjacent angle steels together, the groundwater infiltration channels can be completely sealed off.

Claims

1. A prefabricated diaphragm wall structure, which, viewed from above, comprises multiple component layers extending along the length of the prefabricated diaphragm wall structure, and the multiple component layers include: The top floor, which has multiple top-level prefabricated underground continuous wall structures using precast concrete components; There are N lower layers. When N equals 1, the lower layer is located below the top layer. The lower layer has multiple precast concrete components for the prefabricated diaphragm wall structure of the lower layer. The number of precast concrete components for the prefabricated diaphragm wall structure of the lower layer corresponds to the number of precast concrete components for the prefabricated diaphragm wall structure of the top layer. When N is a natural integer other than 1, the N lower layers are located below the top layer as a whole. The N lower layers are stacked on top of each other in the vertical direction and extend parallel to each other in the length direction of the prefabricated diaphragm wall structure. Each of the N lower layers has multiple precast concrete components for the prefabricated diaphragm wall structure of the lower layer. The number of precast concrete components for the prefabricated diaphragm wall structure in each of the N lower layers corresponds to the number of precast concrete components for the prefabricated diaphragm wall structure of the top layer. In the aforementioned top layer, the horizontally adjacent precast concrete components of the precast underground continuous wall structure are connected by a concave-convex interlocking method. When N equals 1, from the top and bottom direction, during construction, among the precast concrete components of the precast underground continuous wall structure in the top layer and the precast concrete components of the precast underground continuous wall structure in the bottom layer, the horizontal cross-sectional dimension of the precast concrete component of the precast underground continuous wall structure in the top layer is larger than the horizontal cross-sectional dimension of the precast concrete component of the precast underground continuous wall structure in the bottom layer that is adjacent to it above and below. When N is a natural integer other than 1, from the top and bottom direction, during construction, among the precast concrete components of the precast underground continuous wall structure in the top layer and the precast concrete components of the precast underground continuous wall structure in the N lower layers adjacent to the top layer, the horizontal cross-sectional dimension of the precast concrete component of the precast underground continuous wall structure in the top layer is larger than the horizontal cross-sectional dimension of the precast concrete component of the precast underground continuous wall structure in the lower layer that is connected to it above and below. From the horizontal and longitudinal perspective of the continuous wall structure, the precast concrete components of the multiple precast underground continuous wall structures in the lower layer immediately below the top layer are spaced apart from each other at a predetermined distance. Viewed from the thickness direction of the diaphragm wall structure, angle steel is provided at the corner of at least one side of the precast concrete components of the interlocking adjacent precast diaphragm wall structure in the top layer, near the respective ends of the interlocking components. The angle steel provided at the corner of at least one side of the precast concrete components of the interlocking adjacent precast diaphragm wall structure in the top layer is welded together at the respective ends of the interlocking components to prevent water seepage at the joint between the respective ends of the interlocking components.

2. The prefabricated underground continuous wall structure according to claim 1, characterized in that... In the aforementioned top layer, the horizontally adjacent precast concrete components of the precast underground continuous wall structure are connected by mortise and tenon joints.

3. The prefabricated underground continuous wall structure according to claim 1 or 2, characterized in that... The width of the horizontal cross-section of the precast concrete component used in the top-level prefabricated diaphragm wall structure, i.e., the thickness of the precast concrete component used in the top-level prefabricated diaphragm wall structure, is greater than the width of the horizontal cross-section of the precast concrete component used in the lower layer that is connected to it above and below, i.e., the thickness of the precast concrete component used in the lower layer. The length of the horizontal cross-section of the precast concrete component used in the top-level prefabricated diaphragm wall structure, i.e., the length of the precast concrete component used in the top-level prefabricated diaphragm wall structure along the overall horizontal longitudinal direction of the prefabricated diaphragm wall structure, is greater than the length of the horizontal cross-section of the precast concrete component used in the lower layer that is connected to it above and below, i.e., the length of the precast concrete component used in the lower layer along the overall horizontal longitudinal direction of the prefabricated diaphragm wall structure.

4. The prefabricated underground continuous wall structure according to any one of claims 1 to 3, characterized in that... N is 1 in the above N lower layers, that is, there is a total of 1 lower layer.

5. The prefabricated underground continuous wall structure according to any one of claims 1 to 3, characterized in that... The N below layers mentioned above are either 2 or 3, meaning there are a total of two or three below layers.

6. The prefabricated underground continuous wall structure according to any one of claims 1 to 5, characterized in that... The prefabricated underground continuous wall structure at the top layer is connected to the prefabricated underground continuous wall structure below it by bolts using precast concrete components.

7. The prefabricated underground continuous wall structure according to claim 6, characterized in that... The precast concrete components of the top-level prefabricated diaphragm wall structure are connected to the precast concrete components of the lower-level prefabricated diaphragm wall structure perpendicularly adjacent to it by bolts. The top surface of the lower-level prefabricated concrete components of the prefabricated diaphragm wall structure is connected to a connecting end plate, the width of which is greater than that of the lower-level prefabricated concrete components of the prefabricated diaphragm wall structure. Thus, a cantilever portion is formed on the top surface of the lower-level prefabricated concrete components of the prefabricated diaphragm wall structure. Bolt holes are provided in the cantilever portion for the bolts to pass through. A connecting sleeve is connected to the bottom end of the top-level prefabricated diaphragm wall structure. One end of the bolt protrudes below the bottom surface of the connecting end plate, and the other end of the bolt passes through the bolt hole in the plate and is screwed into the connecting sleeve from bottom to top. An anchoring steel bar is installed at the other end of the connecting sleeve, and the other end of the anchoring steel bar is fixed in the top-level prefabricated concrete components of the prefabricated diaphragm wall structure.

8. The prefabricated underground continuous wall structure according to any one of claims 1 to 7, characterized in that... The precast concrete components used in the prefabricated underground continuous wall structures in the top layer and / or the N lower layers are reinforced concrete components.

9. The prefabricated underground continuous wall structure according to any one of claims 1 to 8, characterized in that... The prefabricated underground continuous wall structure in the top layer and / or the N lower layers uses precast concrete components or reinforced concrete components or prestressed concrete components.

10. A construction method for a diaphragm wall using the prefabricated diaphragm wall structure according to any one of claims 1 to 9, characterized in that... This method is used when N equals 1 in the aforementioned N lower layers, and the method includes: a. Prefabrication and transportation of multiple precast concrete components for prefabricated underground continuous wall structures in the top layer and multiple precast concrete components for prefabricated underground continuous wall structures in the lower layer. During the prefabrication of the multiple precast concrete components for prefabricated underground continuous wall structures in the top layer, angle steel is provided at the corner of at least one side of the aforementioned interlocking adjacent precast concrete components for prefabricated underground continuous wall structures near their respective interlocking ends. b. On-site construction of cement-soil mixing walls; c. Before the cement-soil mixing wall is in a fluid state, allowing precast concrete components of the prefabricated diaphragm wall structure in the lower layer to be inserted into the cement-soil mixing wall and placed at the design position and elevation, the precast concrete components of the prefabricated diaphragm wall structure in the lower layer are initially inserted into the cement-soil mixing wall formed by step b, with adjacent precast concrete components of the prefabricated diaphragm wall structure in the lower layer spaced apart by a predetermined interval. The precast concrete components of the prefabricated diaphragm wall structure in the upper layer are then connected to the precast concrete components of the prefabricated diaphragm wall structure in the lower layer that have been initially inserted. d. In order to facilitate the welding of the joints between adjacent angle steels to be welded together, the soil around the aforementioned angle steels is removed, and the adjacent prefabricated diaphragm wall structures in the aforementioned top layer are welded together at the corners of the prefabricated concrete components near their respective interlocking ends along at least one side of the horizontal longitudinal direction of the entire prefabricated diaphragm wall structure to prevent water leakage at the joints at the ends.

11. The construction method according to claim 10, characterized in that... Before the initial setting of the cement-soil mixing wall, step c is performed as follows: The precast concrete components of the first lower layer's prefabricated diaphragm wall structure are inserted into the cement-soil mixing wall; the precast concrete components of the top layer's prefabricated diaphragm wall structure, which are connected to the precast concrete components of the first lower layer's prefabricated diaphragm wall structure already inserted into the cement-soil mixing wall, are connected to the precast concrete components of the first lower layer's prefabricated diaphragm wall structure already inserted into the cement-soil mixing wall; and then, this connection is continued to be made into the cement-soil mixing wall. Continue this process until the design elevation is reached, and so on, until the last prefabricated concrete component of the lower layer of the prefabricated diaphragm wall structure is placed in the cement-soil mixing wall. At the design elevation, connect the last prefabricated concrete component of the top layer of the prefabricated diaphragm wall structure, which is connected to the last prefabricated concrete component of the lower layer of the prefabricated diaphragm wall structure, to the prefabricated concrete component of the last lower layer of the prefabricated diaphragm wall structure that has been implanted in the cement-soil mixing wall. Then, continue implanting it into the cement-soil mixing wall until the design elevation is reached.

12. The construction method according to claim 10, characterized in that... Before the initial setting of the cement-soil mixing wall, step c above is carried out in the following manner: multiple prefabricated concrete components of the prefabricated underground continuous wall structure in the lower layer are placed one by one into the cement-soil mixing wall to the design elevation. Then, multiple prefabricated concrete components of the prefabricated underground continuous wall structure in the top layer are connected one by one to the prefabricated concrete components of the prefabricated underground continuous wall structure in the lower layer that have been set up.

13. The construction method according to any one of claims 11 and 12, characterized in that... Steps a and b above are performed in the following manner: first step a above, then step b above.

14. The construction method according to any one of claims 11 to 13, characterized in that... Steps a and b above are performed in the following manner: step b above is performed first, followed by step a above.

15. The construction method according to any one of claims 11 to 14, characterized in that... Steps a and b above are performed in the following manner: Step b above and step a above are performed simultaneously.

16. The construction method according to any one of claims 11 to 15, characterized in that... Step d above is performed in the following manner: in the joints formed between the ends of the precast concrete components of the multiple prefabricated underground continuous wall structures in the top layer, the angle steels provided at the corners of the adjacent prefabricated concrete components of the prefabricated underground continuous wall structures in the top layer near their respective interlocking ends are welded together at their respective interlocking ends to prevent water leakage at the joints.

17. The construction method according to any one of claims 11 to 16, characterized in that... Step d above is performed in the following manner: for the joints formed between the ends of the precast concrete components of the multiple prefabricated underground continuous wall structures in the top layer, simultaneously for all joints, the angle steels set at the corners of the adjacent prefabricated concrete components of the prefabricated underground continuous wall structures on one side near their respective interlocking ends are welded together at their respective interlocking ends to prevent water leakage at the joints.

18. The construction method according to any one of claims 11 to 17, characterized in that... Step d above is performed in the following manner: In the joints formed between the ends of the precast concrete components of the multiple prefabricated underground continuous wall structures in the top layer, simultaneously for some joints, the angle steels provided at the corners of the adjacent prefabricated concrete components of the prefabricated underground continuous wall structures near their respective interlocking ends are welded together at their respective interlocking ends to prevent water leakage at the joints.

19. The construction method according to any one of claims 11 to 17, characterized in that... The precast concrete components of the top-level prefabricated underground continuous wall structure are connected to the precast concrete components of the lower-level prefabricated underground continuous wall structure, which have been preliminarily installed, by means of bolts.

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