Prefabricated assembled ground-connected wall vertical seam horizontal connection structure and construction method thereof

Abstract

The present invention discloses a prefabricated assembled ground-connected wall vertical seam horizontal connection structure and a construction method thereof, comprising a steel pipe, a sealing ring, a spring ring, a slot device, and a grouting pipe; the steel pipe serves as the main body of the reinforced connection device, the head of which is welded with a hexagonal bolt connected to the slot device, and the tail is fixed in the convex wall; a sealing ring and a spring ring are provided on the steel pipe, which are respectively located at 1 / 3 of the pipe length from the tail end and 1 / 6 of the pipe length from the front end, forming concentric rings; the elastic force of the spring ring drives the slot device to open and close, and the slot device can rotate around the axis and snap into a reserved notch in the slot to prevent it from falling off. The present invention is highly operable and can not only improve the overall rigidity of the prefabricated ground-connected wall and enhance the structural stability, but also has a certain deformation capacity and can adapt to the deformation requirements of the prefabricated continuous wall body. At the same time, through the force transmission mechanism at the joint, the deformation is controlled within a reasonable range, ensuring the safety and stability of the deep foundation pit.

Description

Technical Field

[0001] This project involves strengthening the bearing capacity and overall connection performance of prefabricated ground-connected wall joints in the underground retaining structure of deep foundation pit projects. More specifically, it involves a prefabricated and assembled ground-connected wall vertical seam horizontal connection structure and its construction method. Background Art

[0002] With the increasing development and utilization of underground space, the scale of foundation pit projects has continued to rise, showing a significant trend toward larger and deeper structures. In particular, large-scale foundation pit clusters are becoming increasingly common. While this development has facilitated urban development, it has also brought numerous challenges. When constructing foundation pits in densely populated urban areas, facing the complex and ever-changing surrounding environment, more stringent requirements are placed on the foundation pit support system: ensuring the structural safety and economic efficiency of the foundation pit itself, maintaining the stability of the surrounding environment, and pursuing energy conservation, emission reduction, and sustainable development goals.

[0003] At present, the traditional methods commonly used in my country's foundation pit support field, such as bored cast-in-place piles and underground continuous wall technology, have met the engineering needs to a certain extent, but have exposed many drawbacks: the construction process is inefficient, the working environment is harsh, and quality control is difficult; the large amount of mud discharge generated during the construction process not only increases the environmental burden, but also consumes a lot of energy and resources.

[0004] Precast diaphragm walls are an efficient method for underground structural construction, offering advantages such as fast construction, controlled quality, and minimal environmental impact. During the connection process of precast diaphragm walls, the key is to ensure that the connections between the precast walls are secure and sealed to meet the structural integrity and waterproofing requirements. Research has found that reasonable structural layout and dimensional design of the joints can ensure that the precast diaphragm wall connections can evenly transfer loads and maintain stability when subjected to external forces, which is crucial to the construction quality of precast underground continuous walls and the safety of foundation pits. Reinforced joints are a reasonable and feasible option that can enhance the bearing capacity of the connection parts and improve the bearing performance and stability of precast diaphragm walls.

[0005] However, due to site constraints such as limited space, insufficient light, and poor ventilation, the precise docking of prefabricated diaphragm walls required careful consideration. During assembly, the concave and convex ends of the prefabricated diaphragm walls were butted together, and grouting was injected into the joints on both sides. This effectively transferred the internal forces between the left and right diaphragm walls, while also increasing the bearing capacity of the horizontal joints, filling minor gaps at the joints, and improving the watertightness of the joints, thereby ensuring the overall waterproofing of the underground diaphragm wall. However, the butt-jointing of the concave and convex ends of the prefabricated diaphragm walls required a high degree of precision, which affected the efficiency of the assembly.

[0006] Therefore, it is necessary to design a reinforced prefabricated ground-connected wall connection construction method that can achieve precise docking of prefabricated ground-connected walls, facilitate construction, and effectively transmit force, so as to solve the above technical problems. Summary of the Invention

[0007] The purpose of the present invention is to provide a prefabricated and assembled ground-connected wall vertical seam horizontal connection structure and its construction method, so as to solve the limitations of the prefabricated ground-connected wall connection parts such as weak connection parts and water seepage described in the above background technology. While strengthening the prefabricated ground-connected wall connection and reducing water seepage at the splicing parts, it can also further improve the splicing construction efficiency.

[0008] To achieve the above-mentioned object, the present invention provides the following technical solution: a prefabricated assembled ground-connected wall vertical seam horizontal connection structure, comprising a prefabricated convex wall, a prefabricated concave wall and a reinforced connection device, wherein the prefabricated convex wall and the prefabricated concave wall are horizontally connected by the reinforced connection device;

[0009] The strengthening connection device includes a steel pipe, a sealing ring, a spring ring, a slot device, and a grouting pipe;

[0010] The steel pipe is the main body of the reinforced connection device. The tail of the steel pipe is fixed in the prefabricated convex wall. The head of the steel pipe is welded with a hexagonal bolt. The hexagonal bolt is connected to the slot device via a rotating shaft. The bolt plays a key role in positioning and aligning the reinforced connection device when it is extended into the prefabricated concave wall, ensuring that the prefabricated concave wall and the prefabricated convex wall can achieve precise matching. A cylindrical-hexagonal prism combination groove is provided in the prefabricated concave wall, and the head of the steel pipe extends into the cylindrical-hexagonal prism combination groove.

[0011] The sealing ring is located 1 / 3 of the length of the steel pipe from the rear end and is installed on the outer surface of the steel pipe, forming a concentric ring with the steel pipe. It is a rubber ring with a spring. It is mainly used to provide an additional sealing effect at the connection between the prefabricated concave wall and prefabricated convex wall after grouting is completed, ensuring the integrity and safety of the prefabricated ground-connected wall. At the same time, the sealing ring also provides a certain buffering and protective effect, reducing damage to the connection caused by factors such as vibration and impact, and extending the service life of the reinforced connection device.

[0012] The spring ring is located 1 / 6 of the length of the steel pipe from the head end and is installed on the outer surface of the steel pipe to form a concentric ring with the steel pipe. It is a rubber ring with a spring. The elastic force of the spring can drive the slot device circumscribed to the spring ring to open and close. The main function of the spring ring is to assist the slot device to open smoothly after entering the slot when the reinforced connecting device is extended into the reserved slot of the prefabricated concave wall. The spring ring helps the slot device to accurately snap into the preset notch in the slot through its thrust, thereby ensuring that the prefabricated concave wall and prefabricated convex wall can be stably and firmly installed in place.

[0013] The clamping slot device is located inside the reinforced connection device and is connected to the hexagonal bolt at the end of the steel pipe through a rotating shaft. It can rotate around the shaft. At the same time, the middle part of the clamping slot device is circumscribed to the spring coil. Under the elastic force of the spring coil, the clamping function is realized: in the initial stage when the reinforced connection device is extended into the prefabricated concave wall, due to the annular constraint of the notch of the cylinder-hexagonal prism combination groove, the spring coil will be compressed and drive the clamping slot device to tighten. When the clamping slot device and the spring coil pass through the notch of the cylinder-hexagonal prism combination groove, the annular constraint is released, the spring coil will restore the elastic force, and push the clamping slot device to clamp at the notch;

[0014] The grouting pipe is arranged along the inner wall of the steel pipe and extends into the cylinder-hexagonal prism combination groove of the prefabricated concave wall. After the slot device is clamped in the cylinder-hexagonal prism combination groove, cement mortar is injected into the interlayer between the slot device, the groove wall of the cylinder-hexagonal prism combination groove, the sealing ring, and the spring ring through the grouting pipe to reinforce this part of the space, so as to further improve the overall stiffness of the prefabricated ground-connected wall connection.

[0015] Preferably, the diameter of the steel pipe is 34-60 mm, which is suitable for walls 800-1500 mm thick in actual projects. Three rows of keys can be used according to actual conditions, with double or triple keys in each row. The distance between the steel pipe and the edge of the wall is not less than 50 mm to ensure positioning and anti-drifting. The length L1 of the anchoring section of the steel pipe extending into the prefabricated concave wall is not less than 40d1, where d1 is the diameter of the steel pipe. The tail end of the steel pipe is embedded in the prefabricated convex wall, and the embedding depth L2 needs to be greater than 40d1, where d1 is the diameter of the steel pipe. An anchoring section of a certain length can ensure sufficient contact area and friction between the joint and the concrete, thereby effectively resisting external loads and increasing the bearing capacity of the prefabricated ground-connected wall.

[0016] Preferably, the bolt diameter (M20-M42) selected for the hexagonal bolt should be slightly smaller than or equal to the actual outer diameter of the steel pipe to ensure that the bolt can circumscribe the steel pipe and fit tightly. Stainless steel or carbon steel bolts such as grade 4.8 and grade 8.8 can be selected to meet the requirements of the working environment and corrosion resistance.

[0017] Preferably, the slot device is composed of six steel plate coils, which are made of steel plate coils with a thickness of 5-10mm. The six steel plate coils are respectively combined on the rotating shaft of the hexagonal bolt, and the slot devices composed of the six steel plate coils are all circumscribed on the spring coil. The test ensures that the steel plate coil can rotate around the hexagonal bolt at the end of the steel pipe and realize the opening and closing function under the elastic force of the spring coil; its opening and closing structure makes the joint less likely to loosen and fall off due to vibration or external force after clamping, thereby improving the integrity of the prefabricated ground wall connection; there are also reserved holes on the steel plate coil to facilitate the inflow of slurry during the later grouting, further providing protection for the anti-seepage of the prefabricated ground wall connection.

[0018] Preferably, the grouting pipe is a steel round pipe with a conical tip at the bottom for easy injection into the soil. The diameter of the grouting pipe is 20-50 mm. Two rows of symmetrical eyelet holes are opened in the lower 1 / 3 of the grouting pipe. The diameter of the eyelet holes is 5-8 mm and the spacing is 15 cm to achieve the effect of sufficient grouting reinforcement of the connection. The eyelet holes are sealed with tape before grouting to prevent blockage. The grouting material strength of the grouting pipe is C50.

[0019] The steel pipe, spring coil, and slot device of the present invention are interconnected to form an expandable and contractible mechanism, which together extend into a groove reserved in the concave wall of a prefabricated underground continuous wall. During the initial entry of the reinforced connection device into the concave wall, the spring coil is subjected to pressure and compression due to the annular restriction imposed by the notch. Under the action of the annular pressure, the slot device and the spring coil deform and close together. Once the slot device and spring coil successfully pass through the notch, the annular restriction disappears, and the spring coil releases its elastic force, pushing the slot device to open and firmly clamp at the notch reserved in the concave wall to ensure the tightness of the connection between the concave wall and the convex wall.

[0020] The sealing ring and spring ring of the present invention not only assist in installation and provide sealing, but also promote zoning control during the grouting process. The spring ring is located at 1 / 6 of the pipe length at the front end of the steel pipe, and can serve as a preliminary barrier to the flow of slurry during grouting, guiding the slurry into the first reinforcement area along a predetermined path. The sealing ring is located at 1 / 3 of the pipe length from the tail end of the steel pipe, serving as the starting point of the second grouting area and the end point of the previous area, and can effectively isolate different reinforcement areas to prevent slurries from mixing with each other. The coordinated use of sealing rings and spring rings allows for zoned grouting, which not only provides additional sealing, but also enhances the stability and bearing capacity of the overall structure. In areas with complex geological conditions or uneven settlement, the grouting volume and pressure can be adjusted according to actual conditions to ensure the best grouting effect.

[0021] The construction method of the present invention for strengthening the prefabricated ground-wall connection joint by using a strengthening connection device comprises:

[0022] Step S1: Strengthen the production of the connection device, select a steel pipe with a nominal diameter of 34-60mm according to the actual wall thickness (800-1500mm), and ensure that the material and strength of the steel pipe meet the engineering requirements; the length of the steel pipe should be customized according to the actual wall thickness (800-1500mm) to ensure that the subsequent steel pipe extends into the prefabricated concave wall anchoring section L1 is not less than 40d1 (d1: steel pipe diameter), and its tail can be fixed in the prefabricated convex wall; weld a hexagonal bolt on the head of the steel pipe, and the selected bolt diameter (M20-M42) should be slightly smaller than or equal to the actual outer diameter of the steel pipe to ensure that the bolt can be externally cut into the steel pipe and fit tightly. Stainless steel or carbon steel bolts such as 4.8 and 8.8 can be selected to meet the requirements of the working environment and corrosion resistance. The six sides of the hexagonal bolt are welded with a rotating shaft so that the slot device can rotate around the axis; prepare a rubber ring with a spring as a sealing ring, and ensure that its inner diameter size is consistent with the actual outer diameter of the steel pipe. Match the outer diameter of the steel pipe and fix it to 1 / 3 of the length of the steel pipe at the end to form a concentric ring with the steel pipe and provide additional sealing effect; prepare a rubber ring with a spring as the spring ring, ensure that its inner diameter matches the outer diameter of the steel pipe, and fix it to 1 / 6 of the length of the front end of the steel pipe to form a concentric ring with the steel pipe, ensuring that the size and elasticity of the spring ring and the sealing ring meet the design requirements; select a steel plate with a thickness of 5-10mm to make a slot device, which consists of six steel plate coils. The six steel plate coils are respectively assembled on the rotating shaft of the hexagonal bolt, and the slot device composed of the six steel plate coils is circumscribed to the spring ring. Test to ensure that the steel plate coil can rotate around the hexagonal bolt at the end of the steel pipe and realize the opening and closing function under the elastic force of the spring ring; arrange a steel grouting pipe along the inner wall of the steel pipe. Its diameter is between 20-50mm and the length should match the steel pipe. The bottom is a tapered tip to facilitate injection into the soil;

[0023] Step S2: Production of prefabricated concave wall: First, prepare the reinforcement cage of the prefabricated concave wall, support the formwork and make sure to leave a space in the reserved concrete groove. The space is the cylinder-hexagonal prism combination groove. One end of the cylinder of the cylinder-hexagonal prism combination groove is connected to one bottom surface of the hexagonal prism. The entrance of the prefabricated concave wall groove is the top circular surface of the cylinder. Its diameter needs to be 10 mm larger than the diameter d1 of the steel pipe. The diameter of the circumscribed circle of the bottom surface of the hexagonal prism of the cylinder-hexagonal prism combination groove needs to be 15 mm larger than the diameter d1 of the steel pipe. The height of the cylinder of the cylinder-hexagonal prism combination groove is: L1-(2 / 3)*steel pipe length to ensure that the reinforcing connection device can be smoothly inserted into the groove. Concrete is poured and cured according to the design requirements to complete the production of the prefabricated concave wall.

[0024] Step S3: Production of prefabricated convex wall, the actual wall thickness is 800-1500mm, first make the prefabricated convex wall steel cage, then weld the transverse steel bars to the corresponding position of the steel cage according to the design requirements; set nine connecting keys in three rows and three columns on the butt joint wall to prevent the connection between the prefabricated ground walls from being disconnected, and the connecting key on the side of the prefabricated convex wall close to the wall must be 50mm away from the edge of the wall; the tail of the steel pipe of the strengthening connection device is fixed in the prefabricated convex wall, and the length L2 of its embedded section in the prefabricated convex wall is not less than 40d1, d1 is the diameter of the steel pipe, and a certain length of anchor section can be fixed. This ensures sufficient contact area and friction between the joint and the concrete, effectively resisting external loads and increasing the bearing capacity of the prefabricated ground-connected wall. Secondly, the grouting pipe embedded in the steel pipe extends upward from the tail of the steel pipe, ensuring that the grouting pipe extends from the top of the prefabricated convex wall, facilitating the subsequent grouting work after the splicing is completed. Finally, beard reinforcement is tied to the tail of the steel pipe to connect it to the prefabricated convex wall through casting, making it difficult for the joint to fall out of the prefabricated convex wall. After casting, maintenance work is carried out to ensure that the concrete meets the design strength and other performance indicators, completing the production of the prefabricated convex wall.

[0025] Step S4: Ground preparation and measurement to ensure the foundation is flat and solid, and the wall positions are marked; the first prefabricated wall is hoisted to the designated location using a crane and adjusted to a vertical level; the second wall is installed using the same method, and after precise alignment, it is pushed into place to ensure that the redundant steel bars enter the grooves of the cylinder-hexagonal prism combination and that the concave and convex wall axes coincide;

[0026] Step S5: When the end of the reinforced connection device of the prefabricated convex wall enters the cylindrical-hexagonal prism combination groove reserved in the prefabricated concave wall, it first passes through the cylindrical groove. At this time, the clamping groove device and the spring ring are first subjected to the circumferential constraint of the cylindrical groove, shrinking and closing inward to pass through the cylindrical groove. After entering the hexagonal groove, the clamping groove device opens outward under the elastic force of the spring ring, clamping the groove wall. When the sealing ring is compressed through the cylindrical groove and enters the hexagonal groove and cannot move forward, the prefabricated concave wall and the prefabricated convex wall are preliminarily connected;

[0027] Step S6: Pull the prefabricated convex wall outward horizontally to ensure that the slot device is firmly clamped to the prefabricated concave wall groove wall, and check whether the sealing ring is dislodged. If it is not dislodged, it means that the groove has been sealed, and the mechanical installation inside and outside the wall is completed; if the sealing ring does not enter the hexagonal prism groove or is dislodged, repeat step S5 for secondary installation;

[0028] Step S7: Grouting reinforcement is performed inside the gaps of the prefabricated concave wall and the prefabricated convex wall through the reserved grouting pipe.

[0029] Beneficial effects: Compared with the prior art, the technical advantages of the present invention are:

[0030] The present invention provides a technology and construction method for horizontal connection of vertical seams of prefabricated assembled ground-connected walls, which realizes efficient connection and excellent sealing performance through the combined design of a slot device and a spring ring, and the use of a sealing ring. The slot device can realize the opening and closing function under the elastic force of the spring ring, smoothly enter and clamp the hexagonal prism-shaped slot wall of the prefabricated concave wall. The sealing ring ensures the sealing of the connection, prevents the leakage of slurry during the grouting process, realizes the precise positioning of the splicing, and solves the problem of weakening of the connection of the previous prefabricated ground-connected walls, thereby improving the overall stiffness of the underground continuous wall; finally, the grouting process is adopted, and the spring ring and the sealing ring can realize the partitioned reinforcement of the grouting in the groove, while the sealing ring can prevent the slurry from seeping out of the groove, optimizing the connection effect and the water-stopping effect of the joint. This method also optimizes construction procedures and improves efficiency. Through a series of steps, including foundation preparation, wall hoisting, docking adjustment, clamping of the slot device, sealing ring inspection, and grouting reinforcement, it achieves rapid and accurate connection of prefabricated ground-connected walls. Compared to traditional connection methods, this method not only shortens construction time but also reduces subsequent maintenance costs. Furthermore, while enhancing the overall rigidity and load-bearing capacity of the prefabricated ground-connected wall connection, the materials used in this invention meet environmental requirements, reducing environmental pollution during construction. The efficient construction method reduces energy consumption, aligning with the concept of sustainable development. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a bird's-eye view of the wall panel splicing of the present invention.

[0032] Figure 2 It is a top view of the joint of the present invention before docking.

[0033] Figure 3 It is a top view of the joint after docking of the present invention.

[0034] Figure 4 This is a schematic diagram of a single reserved groove after the prefabricated concave wall of the present invention is completed.

[0035] Figure 5 Schematic diagram of a steel pipe of a single reinforced connection device of the present invention.

[0036] Figure 6 This is a schematic diagram of the positional relationship between the sealing ring, spring ring and steel pipe after the prefabricated convex wall of the present invention is installed.

[0037] Figure 7 It is a large-scale drawing of the card slot device of the present invention.

[0038] Figure 8 It is a schematic diagram of the positional relationship between the grouting pipe and the steel pipe after the prefabricated convex wall of the present invention is installed. DETAILED DESCRIPTION

[0039] The following is a clear and complete description of the technical solutions in the embodiments of the present invention, in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0040] See also Figure 1-8 A prefabricated and assembled ground-connected wall vertical joint horizontal connection structure includes a prefabricated convex wall 6, a prefabricated concave wall 7, and a reinforced connection device. The prefabricated convex wall 6 and the prefabricated concave wall 7 are horizontally connected by the reinforced connection device; the reinforced connection device includes a steel pipe 1, a sealing ring 2, a spring ring 3, a slot device 4, and a grouting pipe 5;

[0041] The steel pipe 1 is the main body of the strengthening connection device. The tail of the steel pipe 1 is fixed in the prefabricated convex wall 6. The head of the steel pipe 1 is welded with a hexagonal bolt 9. The hexagonal bolt 9 is connected to the slot device 4 through a rotating shaft 10. The bolt plays a key role in positioning and aligning the strengthening connection device when it extends into the prefabricated concave wall, ensuring that the prefabricated concave wall and the prefabricated convex wall can be accurately matched; a cylindrical-hexagonal prism combination groove is provided in the prefabricated concave wall 7, and the head of the steel pipe 1 extends into the cylindrical-hexagonal prism combination groove; the diameter of the steel pipe 1 is 34-60mm, which is suitable for 800-1500mm thick in actual engineering. The wall can be keyed in three rows, each row with either double or triple keys, depending on the actual situation. The distance between the steel pipe 1 and the wall edge should be no less than 50mm to ensure positioning and prevent deviation. The length L1 of the anchoring section of the steel pipe 1 extending into the prefabricated concave wall 7 should be no less than 40d1, where d1 is the diameter of the steel pipe. The end of the steel pipe 1 is embedded in the prefabricated convex wall, and the embedding depth L2 must be greater than 40d1, where d1 is the diameter of the steel pipe. This anchoring section ensures sufficient contact area and friction between the joint and the concrete, effectively resisting external loads and increasing the bearing capacity of the prefabricated ground-connected wall. The bolt diameter (M20-M42) of the hexagonal bolt 9 should be slightly smaller than or equal to the actual outer diameter of the steel pipe 1 to ensure that the bolt can circumscribe the steel pipe and fit tightly. Stainless steel or carbon steel bolts, such as grade 4.8 or 8.8, can be selected to meet the working environment and corrosion resistance requirements.

[0042] The sealing ring 2 is located one-third of the length of the steel pipe 1 from its end and is installed on its outer surface, forming a concentric ring with the pipe 1. It is a rubber ring with a spring. It is primarily used to provide an additional seal at the joint after grouting is completed between the prefabricated concave wall and the prefabricated convex wall, ensuring the integrity and safety of the prefabricated ground-connected wall. It also provides a certain buffering and protective effect, reducing damage to the connection caused by factors such as vibration and impact, thereby extending the service life of the reinforced connection device.

[0043] The spring ring 3 is located 1 / 6 of the length of the steel pipe 1 from the head end and is installed on the outer surface of the steel pipe 1 to form a concentric ring with the steel pipe 1. It is a rubber ring with a spring. The elastic force of the spring can drive the slot device 4 circumscribed to the spring ring 3 to open and close. The main function of the spring ring 3 is to assist the slot device 4 to open smoothly after entering the slot when the reinforced connecting device is extended into the reserved slot of the prefabricated concave wall. The spring ring 3 also helps the slot device to accurately snap into the preset notch in the slot through its thrust, thereby ensuring that the prefabricated concave wall and prefabricated convex wall can be stably and firmly installed in place.

[0044] The clamping slot device 4 is located inside the strengthening connection device, and is connected to the hexagonal bolt 9 at the end of the steel pipe 1 through the rotating shaft 10, and can rotate around the axis. At the same time, the middle part of the clamping slot device 4 is circumscribed on the spring coil 3, and the clamping function is realized under the elastic force of the spring coil 3: in the initial stage when the strengthening connection device extends into the prefabricated concave wall 7, due to the annular constraint of the notch of the cylinder-hexagonal prism combination groove, the spring coil 3 will be compressed and drive the clamping slot device 4 to tighten. When the clamping slot device 4 and the spring coil 3 pass through the notch of the cylinder-hexagonal prism combination groove, the annular constraint is released, the spring coil 3 will restore the elastic force, and push the clamping slot device 4 to clamp at the notch; the clamping slot device 4 is clamped at the notch. The slot device 4 is composed of six steel plate coils, which are made of steel plate coils with a thickness of 5-10mm. The six steel plate coils are respectively combined on the rotating shaft 10 of the hexagonal bolt 9, and the slot devices composed of the six steel plate coils are all circumscribed on the spring coil. The test ensures that the steel plate coil can rotate around the hexagonal bolt 9 at the end of the steel pipe 1 and realize the opening and closing function under the elastic force of the spring coil 3; its opening and closing structure makes the joint less likely to loosen and fall off due to vibration or external force after clamping, thereby improving the integrity of the prefabricated ground wall connection; there are also reserved holes on the steel plate coil to facilitate the inflow of slurry during the later grouting, further providing protection for the anti-seepage of the prefabricated ground wall connection.

[0045] The grouting pipe 5 is arranged along the inner wall of the steel pipe 1 and extends into the cylindrical-hexagonal prism combination groove of the prefabricated concave wall 7. After the slot device 4 is clamped in the cylindrical-hexagonal prism combination groove, cement mortar is injected through the grouting pipe 5 into the interlayer between the slot device 4, the groove wall of the cylindrical-hexagonal prism combination groove, the sealing ring 2, and the spring ring 3 to reinforce this part of the space and further improve the overall stiffness of the prefabricated ground-connected wall connection. The grouting pipe 5 is a steel circular tube with a tapered tip at the bottom for easy insertion into the soil. The diameter of the grouting pipe 5 is 20-50mm. Two rows of symmetrical perforated holes are opened within the lower 1 / 3 of the grouting pipe 5. The perforated holes have a diameter of 5-8mm and are spaced 15cm apart to achieve the effect of sufficient grouting and reinforcement of the connection. The perforated holes are sealed with tape before grouting to prevent clogging. The grouting material strength of the grouting pipe 5 is C50.

[0046] The present invention realizes precise positioning of splicing; the mechanism of the spring ring 3 driving the slot device 4 to open and close can significantly solve the weak problem of the connection of the prefabricated underground continuous wall, thereby improving the overall stiffness of the underground continuous wall; the grouting pipe 5 is reserved in the convex wall, and the grouting process can be used after the concave wall and the convex wall are spliced, which can effectively prevent water seepage and optimize the connection effect; the sealing ring 2 and the spring ring 3 work together to realize the partition reinforcement of the grouting in the groove, and the sealing ring 2 also plays an additional role in preventing the slurry from leaking out of the groove, significantly enhancing the waterproof performance of the joint.

[0047] The specific implementation steps of the present invention are described below:

[0048] Step S1: Strengthen the production of the connecting device. According to the actual wall thickness of 800-1500mm, select a steel pipe 1 with a diameter of 34-60mm to ensure that the material and strength of the steel pipe 1 meet the engineering requirements. The length of the steel pipe 1 should be customized according to the actual wall thickness of 800-1500mm to ensure that the subsequent steel pipe 1 extends into the prefabricated concave wall 7. The anchoring section length L1 is not less than 40d1, d1 is the diameter of the steel pipe, and the tail of the steel pipe 1 can be fixed in the prefabricated convex wall 6; weld a hexagonal bolt 9 at the head of the steel pipe 1, and weld a rotating shaft 10 on the six edges of the hexagonal bolt 9 so that the slot device 4 can rotate around the axis; prepare a rubber ring with a spring as a sealing ring 2, ensure that its inner diameter matches the outer diameter of the steel pipe 1, and fix it to the tail end of the steel pipe 1 at 1 / 3 of the pipe length to form a concentric ring with the steel pipe 1 and provide additional sealing effect. ; Prepare a rubber ring with a spring as the spring ring 3, ensure that its inner diameter matches the outer diameter of the steel pipe 1, fix it at 1 / 6 of the pipe length at the front end of the steel pipe 1, and form a concentric ring with the steel pipe 1 to ensure that the size and elasticity of the spring ring 3 and the sealing ring 2 meet the design requirements; Select a steel plate with a thickness of 5-10mm to roll into the slot device 4, the slot device 4 consists of six steel plate coils, and the six steel plate coils are respectively assembled on the rotating shaft of the hexagonal bolt 9, and the slot device 4 composed of the six steel plate coils is circumscribed to the spring ring 3, and the test ensures that the steel plate coil can rotate around the hexagonal bolt 9 at the end of the steel pipe 1 and realize the opening and closing function under the elastic force of the spring ring 3; Arrange a steel grouting pipe 5 along the inner wall of the steel pipe 1, with a diameter between 20-50mm and a length that should match the steel pipe 1, and the bottom is a conical tip, which is convenient for driving into the soil;

[0049] Step S2: Production of the prefabricated concave wall 7. First, a steel cage for the prefabricated concave wall 7 is produced. The formwork is supported and a blank is left at the reserved concrete groove. The blank is a cylinder-hexagonal prism combination groove. One end of the cylinder of the cylinder-hexagonal prism combination groove is connected to a bottom surface of the hexagonal prism. The entrance of the groove of the prefabricated concave wall 7 is a circular top surface of the cylinder. Its diameter needs to be 10 mm larger than the diameter d1 of the steel pipe. The diameter of the circumscribed circle of the bottom surface of the hexagonal prism of the cylinder-hexagonal prism combination groove needs to be 15 mm larger than the diameter d1 of the steel pipe. The height of the cylinder of the cylinder-hexagonal prism combination groove is: L1-(2 / 3)*steel pipe length to ensure that the reinforcing connection device is smoothly inserted into the groove. Concrete is poured and cured according to the design requirements to complete the production of the prefabricated concave wall.

[0050] Step S3: Production of prefabricated convex wall 6. The actual wall thickness is 800-1500mm. Taking a 6000mm high prefabricated convex wall as an example, first make a prefabricated convex wall steel cage, and then weld the transverse steel bars to the corresponding positions of the steel cage according to the design requirements; nine connecting keys are evenly spaced in three rows and three columns on the butt joint wall to prevent the connection between the prefabricated ground connecting walls from being detached. It is particularly important to note that the connecting key on the side of the prefabricated convex wall 6 close to the wall must be 50mm away from the edge of the wall; the tail of the steel pipe 1 of the strengthening connection device is fixed in the prefabricated convex wall 6, and its embedded section length L2 in the prefabricated convex wall 6 is not less than 40d1, where d1 is the straightness of the steel pipe. The anchoring section of a certain diameter and length can ensure that there is sufficient contact area and friction between the joint and the concrete, thereby effectively resisting external loads and increasing the bearing capacity of the prefabricated ground-connected wall. Secondly, the grouting pipe 5 embedded in the steel pipe 1 extends upward from the tail of the steel pipe 1, ensuring that the grouting pipe 5 extends from the top of the prefabricated convex wall, facilitating the subsequent grouting work after the splicing is completed. Finally, beard reinforcement is tied to the tail of the steel pipe 1 and poured and connected to the prefabricated convex wall 6, making it difficult for the joint to fall out of the prefabricated convex wall 6. After pouring, maintenance work is carried out to ensure that the concrete meets the design strength and other performance indicators, completing the production of the prefabricated convex wall.

[0051] Step S4: Ground preparation and measurement to ensure the foundation is flat and solid, and the wall positions are marked; the first prefabricated wall is hoisted to the designated location using a crane and adjusted to a vertical level; the second wall is installed using the same method, and after precise alignment, it is pushed into place to ensure that the redundant steel bars enter the grooves of the cylinder-hexagonal prism combination and that the concave and convex wall axes coincide;

[0052] Step S5: When the end of the reinforced connection device of the prefabricated convex wall 6 enters the cylindrical-hexagonal prism combination groove reserved in the prefabricated concave wall 7, it will first pass through the cylindrical groove. At this time, the clamping groove device 4 and the spring ring 3 are first subjected to the annular constraint of the cylindrical groove, shrinking and closing inward to pass through the cylindrical groove. After entering the hexagonal groove, the clamping groove device 4 is pushed outward by the elastic force of the spring ring 3, clamping the groove wall. When the sealing ring 2 is compressed through the cylindrical groove and enters the hexagonal groove and cannot move forward, the docking of the prefabricated concave wall 7 and the prefabricated convex wall 6 is preliminarily completed;

[0053] Step S6: Pull the prefabricated convex wall 6 outward horizontally to ensure that the slot device 4 is firmly clamped to the groove wall of the prefabricated concave wall 7, and check whether the sealing ring is out of place. If it is not out of place, it means that the groove has been sealed, and the mechanical installation inside and outside the wall is completed; if the sealing ring 2 does not enter the hexagonal groove or is out of place, repeat step S5 for secondary installation;

[0054] Step S7: Grouting reinforcement is performed inside the gaps between the prefabricated concave wall 7 and the prefabricated convex wall 6 through the reserved grouting pipe 5 .

[0055] The working principle of the present invention is described below:

[0056] The tail of the steel pipe is fixed in the convex wall, and the axis of the steel pipe is aligned with the axis of the joint connection of the prefabricated concave wall. This step ensures the accuracy and stability of the subsequent connection. Using a combination of steel pipe, spring coil, and slot device, they are inserted into the reserved groove in the concave wall. During the initial entry stage, the spring coil is compressed due to the circumferential restriction of the cylindrical channel reserved in the concave wall, and drives the slot device to tighten to pass through the channel. Once they enter the hexagonal prism groove, the spring coil regains its elastic force due to the release of the circumferential constraint, pushing the slot device outward and firmly snapping into the preset notch in the groove, thus effectively preventing the reinforced connection device from loosening. Next, the convex wall is pushed until the required anchoring length is met (anchoring length L1 ≥ 40d). During this process, the slot device fully opens and grasps the groove wall, and the steel pipe is firmly fixed in the groove. At the same time, the sealing ring also enters the hexagonal groove through the cylindrical channel of the concave wall groove and transitions from a compressed state to a normal state, sealing the groove opening. This, to a certain extent, solves the weakening problem of the prefabricated ground-connected wall joint and enhances the strength and stability of the prefabricated ground-connected wall connection. Once the connection device is fully in place and secured, cement mortar is injected between the steel pipe, the slot device, and the groove wall through the grouting pipe reserved on the inner wall of the steel pipe to increase the overall rigidity of the prefabricated ground-connected wall connection. During this process, the sealing ring and spring coil work together to achieve zoned reinforcement of the grouting within the groove. At the same time, the sealing ring prevents slurry leakage, ensuring the overall waterproof performance of the prefabricated ground-connected wall assembly. This joint type also fully utilizes the load-bearing capacity of the prefabricated ground-connected wall by improving integrity and avoiding economic waste.

[0057] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A prefabricated and assembled ground-connected wall vertical seam horizontal connection structure, characterized by: It comprises a prefabricated convex wall (6), a prefabricated concave wall (7) and a reinforced connection device, wherein the prefabricated convex wall (6) and the prefabricated concave wall (7) are horizontally butted together via the reinforced connection device; The strengthening connection device comprises a steel pipe (1), a sealing ring (2), a spring ring (3), a slot device (4), and a grouting pipe (5); The steel pipe (1) is the main body of the reinforced connection device. The tail of the steel pipe (1) is fixed in the prefabricated convex wall (6). The head of the steel pipe (1) is welded with a hexagonal bolt (9). The hexagonal bolt (9) is connected to the slot device (4) through a rotating shaft (10). The prefabricated concave wall (7) is provided with a cylindrical-hexagonal prism combination groove. The head of the steel pipe (1) extends into the cylindrical-hexagonal prism combination groove. The sealing ring (2) is located at 1 / 3 of the length of the steel pipe (1) from the tail end, is installed on the outer surface of the steel pipe (1), forms a concentric ring with the steel pipe (1), and is a rubber ring with a spring; The spring ring (3) is located 1 / 6 of the length of the steel pipe (1) from the head end, is installed on the outer surface of the steel pipe (1), and forms a concentric ring with the steel pipe (1). It is a rubber ring with a spring, and the elastic force of the spring drives the slot device (4) circumscribed to the spring ring (3) to open and close; The slot device (4) is located inside the reinforced connection device and is connected to the hexagonal bolt (9) at the end of the steel pipe (1) through a rotating shaft (10). It can rotate around the shaft. At the same time, the middle part of the slot device (4) is circumscribed to the spring coil (3). Under the elastic force of the spring coil (3), a clamping function is realized: in the initial stage when the reinforced connection device extends into the prefabricated concave wall (7), due to the annular constraint of the notch of the cylindrical-hexagonal prism combination groove, the spring coil (3) will be compressed and drive the slot device (4) to tighten. When the slot device (4) and the spring coil (3) pass through the notch of the cylindrical-hexagonal prism combination groove, the annular constraint is released, and the spring coil (3) will restore the elastic force, pushing the slot device (4) to clamp at the notch. The grouting pipe (5) is arranged along the inner wall of the steel pipe (1) and extends into the cylinder-hexagonal prism combination groove of the prefabricated concave wall (7). After the slot device (4) is clamped in the cylinder-hexagonal prism combination groove, cement mortar is injected into the interlayer between the slot device (4), the groove wall of the cylinder-hexagonal prism combination groove, the sealing ring (2), and the spring ring (3) through the grouting pipe (5).

2. The prefabricated and assembled ground-connected wall vertical seam horizontal connection structure according to claim 1, characterized in that: The steel pipe (1) has a diameter of 34-60 mm and is suitable for walls with a thickness of 800-1500 mm. It adopts three rows of keys, with double keys or triple keys in each row. The distance between the steel pipe (1) and the edge of the wall is not less than 50 mm. The length L1 of the anchoring section of the steel pipe (1) extending into the prefabricated concave wall (7) is not less than 40d1, where d1 is the diameter of the steel pipe. The tail end of the steel pipe (1) is embedded in the prefabricated convex wall (6), and the embedding depth L2 needs to be greater than 40d1, where d1 is the diameter of the steel pipe.

3. The prefabricated and assembled ground-connected wall vertical seam horizontal connection structure according to claim 2 is characterized in that: The bolt diameter selected for the hexagonal bolt (9) should be slightly smaller than or equal to the actual outer diameter of the steel pipe (1), and stainless steel or carbon steel bolts of grade 4.8 or 8.8 should be selected.

4. The prefabricated and assembled ground-connected wall vertical seam horizontal connection structure according to claim 3 is characterized by: The slot device (4) is made of a steel plate coil with a thickness of 5-10 mm, and the steel plate coil is provided with reserved holes for slurry to flow in during the subsequent grouting.

5. The prefabricated and assembled ground-connected wall vertical seam horizontal connection structure according to claim 4 is characterized in that: The grouting pipe (5) is a steel round pipe with a conical tip at the bottom for easy insertion into the soil. The diameter of the grouting pipe (5) is 20-50 mm. Two rows of symmetrical eyelet holes are opened within the lower 1 / 3 of the grouting pipe (5). The eyelet holes have a diameter of 5-8 mm and a spacing of 15 cm. The eyelet holes are sealed with tape before grouting. The strength of the grouting material of the grouting pipe (5) is C50.

6. A construction method for the prefabricated assembled ground-connected wall vertical seam horizontal connection structure according to claim 1, 2, 3, 4 or 5, characterized in that: The following steps are involved: Step S1: Strengthen the production of the connection device. According to the actual wall thickness of 800-1500mm, a steel pipe (1) with a diameter of 34-60mm is selected to ensure that the material and strength of the steel pipe (1) meet the engineering requirements. The length of the steel pipe (1) should be customized according to the actual wall thickness of 800-1500mm to ensure that the subsequent steel pipe (1) extends into the prefabricated concave wall (7) with an anchoring section length L1 of not less than 40d1, where d1 is the diameter of the steel pipe. The tail of the steel pipe (1) can be fixed in the prefabricated convex wall (6); a hexagonal bolt (9) is welded to the head of the steel pipe (1), and a rotating shaft (10) is welded on the six edges of the hexagonal bolt (9) so that the slot device (4) can rotate around the axis; a rubber ring with a spring is prepared as a sealing ring (2), ensuring that its inner diameter matches the outer diameter of the steel pipe (1), and it is fixed to the tail end of the steel pipe (1) at 1 / 3 of the pipe length to form a concentric ring with the steel pipe (1) and provide an additional sealing effect; Prepare a rubber ring with a spring as the spring ring (3), ensure that its inner diameter matches the outer diameter of the steel pipe (1), fix it to the front end of the steel pipe (1) at 1 / 6 of the pipe length, form a concentric ring with the steel pipe (1), and ensure that the size and elasticity of the spring ring (3) and the sealing ring (2) meet the design requirements; select a steel plate with a thickness of 5-10mm to roll into a slot device (4), the slot device (4) consists of six steel plate rolls, and the six steel plate rolls are respectively assembled on the rotating shaft of the hexagonal bolt (9), and the slot device (4) composed of the six steel plate rolls is circumscribed to the spring ring (3), and test to ensure that the steel plate roll can rotate around the hexagonal bolt (9) at the end of the steel pipe (1) and realize the opening and closing function under the elastic force of the spring ring (3); arrange a steel grouting pipe (5) along the inner wall of the steel pipe (1), the diameter of which is between 20-50mm, the length of which should match the steel pipe (1), and the bottom is a conical tip, which is convenient for driving into the soil; Step S2: Production of the prefabricated concave wall (7). First, a steel cage of the prefabricated concave wall (7) is produced. The formwork is supported and a space is left at the reserved concrete groove. The space is a cylinder-hexagonal prism combination groove. One end of the cylinder of the cylinder-hexagonal prism combination groove is connected to a bottom surface of the hexagonal prism. The entrance of the prefabricated concave wall (7) groove is a circular top surface of the cylinder. Its diameter needs to be reserved 10 mm more than the diameter d1 of the steel pipe. The diameter of the circumscribed circle of the bottom surface of the hexagonal prism of the cylinder-hexagonal prism combination groove needs to be reserved 15 mm more than the diameter d1 of the steel pipe. The height of the cylinder of the cylinder-hexagonal prism combination groove is: L1-(2 / 3)*steel pipe length to ensure that the reinforcing connection device is smoothly inserted into the groove. Concrete is poured and maintained according to the design requirements to complete the production of the prefabricated concave wall. Step S3: Production of prefabricated convex wall (6), the actual wall thickness is 800-1500mm, taking the 6000mm high prefabricated convex wall as an example, firstly, a prefabricated convex wall steel cage is produced, and then the transverse steel bars are welded to the corresponding positions of the steel cage according to the design requirements; nine connecting keys are evenly arranged in three rows and three columns on the butt joint wall to prevent the connection between the prefabricated ground connecting walls from being separated. It should be noted that the connecting key of the prefabricated convex wall (6) close to the wall side needs to be 50mm away from the wall edge; the tail of the steel pipe (1) of the strengthening connection device is fixed in the prefabricated convex wall (6), and the length L2 of the embedded section in the prefabricated convex wall (6) is not less than 40d1, d1 is the diameter of the steel pipe, and one The fixed length anchoring section can ensure that there is sufficient contact area and friction between the joint and the concrete, thereby effectively resisting external loads and increasing the bearing capacity of the prefabricated ground-connected wall; secondly, the grouting pipe (5) pre-buried in the steel pipe (1) extends upward from the tail of the steel pipe (1), ensuring that the grouting pipe (5) extends from the top of the prefabricated convex wall (6), facilitating the subsequent grouting work after the splicing is completed; finally, the beard reinforcement is tied to the tail of the steel pipe (1) and connected to the prefabricated convex wall (6) by pouring, so that the joint is not easy to fall out of the prefabricated convex wall (6); after the pouring is completed, maintenance work is carried out to ensure that the concrete reaches the strength and other performance indicators required by the design, and the production of the prefabricated convex wall is completed; Step S4: Ground preparation and measurement to ensure the foundation is flat and solid, and the wall positions are marked; the first prefabricated wall is hoisted to the designated location using a crane and adjusted to a vertical level; the second wall is installed using the same method, and after precise alignment, it is pushed into place to ensure that the redundant steel bars enter the grooves of the cylinder-hexagonal prism combination and that the concave and convex wall axes coincide; Step S5: When the end of the reinforced connection device of the prefabricated convex wall (6) enters the cylindrical-hexagonal prism combination groove reserved in the prefabricated concave wall (7), it will first pass through the cylindrical groove. At this time, the clamping groove device (4) and the spring ring (3) are first subjected to the annular constraint of the cylindrical groove, shrink and close inward to pass through the cylindrical groove. After entering the hexagonal prism groove, the clamping groove device (4) is pushed outward by the elastic force of the spring ring (3) to clamp the groove wall. When the sealing ring (2) is compressed through the cylindrical groove and enters the hexagonal prism groove and cannot move forward, the docking of the prefabricated concave wall (7) and the prefabricated convex wall (6) is preliminarily completed; Step S6: Pull the prefabricated convex wall (6) outward horizontally to ensure that the slot device (4) is clamped to the slot wall of the prefabricated concave wall (7), and check whether the sealing ring is out of place. If it is not out of place, it means that the slot has been sealed and the mechanical installation inside and outside the wall is completed; if the sealing ring (2) does not enter the hexagonal prism slot or is out of place, repeat step S5 for secondary installation; Step S7: Grouting reinforcement is performed inside the gaps between the prefabricated concave wall (7) and the prefabricated convex wall (6) through the reserved grouting pipe (5).

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