Construction method for enhancing joint water stop effect of underground diaphragm wall

Abstract

A construction method for enhancing the joint waterstop effect of an underground diaphragm wall comprises the steps that after an underground diaphragm wall formwork is placed in a foundation pit, an underground diaphragm wall framework unit at the starting end, a plurality of underground diaphragm wall framework units at the middle sections and an underground diaphragm wall framework unit at the terminating end are sequentially placed in the formwork, and each underground diaphragm wall framework unit comprises a reinforcement cage and H-shaped steel at the end; a limiting inclined plate is arranged at the included angle position of the outer side face of the H-shaped steel, after the outer side face of the H-shaped steel in the previous underground diaphragm wall framework unit is cleaned, the next underground diaphragm wall framework unit continues to be placed, and after placing is completed, a grouting pipe and a water stop steel plate are vertically inserted into the included angle position in the limiting inclined plate; concrete grout is injected into the position of the reinforcement cage to form the underground diaphragm wall, before the underground diaphragm wall is condensed and hardened, cement grout is injected into the grouting pipe, the grout at the position of the replacement included angle is squeezed out, and the cleaning quality of the grout is improved.

Description

Technical Field

[0001] The invention relates to the technical field of underground continuous wall joint construction, in particular to a construction method for strengthening the water-stopping effect of underground continuous wall joints. Background Art

[0002] The underground continuous wall is a foundation project that uses a trenching machine on the ground to dig a long and narrow deep trench along the peripheral axis of the deep excavation project under the condition of mud wall protection. After the trench is cleaned, a steel cage is suspended in the trench, and then underwater concrete is poured using the conduit method to build a unit trench section. This is done section by section to build a continuous reinforced concrete wall underground as a water interception, anti-seepage, load-bearing, and water-retaining structure. In order to ensure the continuity of the ground-connected wall and the corresponding waterproof performance, in the above-mentioned section-by-section construction process, H-shaped steel is generally set between adjacent ground-connected walls as a water-stopping joint structure, but the mud at the angle of the inner surface of the existing H-shaped steel is difficult to clean, which will affect the density of the ground-connected wall after the later concrete pouring, forming structural defects such as leaks, significantly reducing the strength, and there is a seepage path for groundwater, and the corresponding joint water-stopping effect cannot be achieved. Summary of the invention

[0003] The purpose of the present invention is to provide a construction method for strengthening the water-stopping effect of underground continuous wall joints. On the basis of the original H-shaped steel, a limiting inclined plate and a matching grouting pipe and a water-stopping steel plate are added to extend the water flow path to play a water-stopping role. Before the ground-connected wall solidifies and hardens, cement slurry is injected to squeeze out and replace the mud and residual slag at the angle position, thereby enhancing the density of the overall ground-connected wall and solving the problems in the prior art.

[0004] The technical solution adopted by the present invention to solve its technical problems is: a construction method for strengthening the water-stopping effect of underground continuous wall joints, comprising the following steps: ① placing several groups of underground continuous wall formworks in a foundation pit close to one side of the soil body, and placing a ground-connected wall skeleton unit at the starting end in the underground continuous wall formwork, the ground-connected wall skeleton unit at the starting end comprises a steel cage and H-shaped steel at both ends of the steel cage, wherein the H-shaped steel is composed of flange plates on both sides and web plates between the flange plates, two corresponding limiting inclined plates are arranged at the angle position between the flange plates and the web plates on the outer sides of the H-shaped steel, a gap is left between the two limiting inclined plates, and a grouting pipe is fixedly connected to the angle position between the flange plates and the web plates on the inner sides of the H-shaped steel, and a grouting pipe is fixedly connected to the grouting pipe The flange plate on one side of the pipe is fixedly connected to the steel cage; ② After the placement of the ground-connected wall frame unit at the starting end in step ① is completed, use a crawler crane with a brush to clean the mud on the outer side of the H-shaped steel in the ground-connected wall frame unit at the starting end, and prepare for the subsequent lowering of the ground-connected wall frame unit in the middle part; ③ After the cleaning operation in step ② is completed, place the middle section of the ground-connected wall frame unit into the underground continuous wall formwork. The middle section of the ground-connected wall frame unit includes a steel cage and an H-shaped steel at one end of the steel cage. The H-shaped steel is far away from the ground-connected wall frame unit at the starting end, and the end of the steel cage without the H-shaped steel extends between the two flange plates of the H-shaped steel in the ground-connected wall frame unit at the starting end, and the ground-connected wall frame unit in the middle section is cleaned. ④ Repeat step ③ to complete the installation of multiple sets of middle-section ground-connected wall frame units, and install the terminal-end ground-connected wall frame unit at the most end position, the terminal-end ground-connected wall frame unit only includes a steel cage, one end of the steel cage extends between the two flange plates of the H-shaped steel in the previous middle-section ground-connected wall frame unit, and the other end of the steel cage cooperates with the H-shaped steel pre-set in the underground continuous wall formwork; ⑤ After the middle-section ground-connected wall frame unit and the terminal-end ground-connected wall frame unit in step ④ are placed, a grouting pipe is vertically inserted into the space formed by the limiting inclined plate, the flange plate and the web plate, wherein the outer periphery of the grouting pipe is provided with grouting holes, and the grouting pipe is also connected to a water-stop steel Plate, the waterstop steel plate matches the gap between the two limiting inclined plates, and the end of the waterstop steel plate contacts the steel cage; ⑥ After the grouting pipe in step ⑤ is installed, concrete slurry is injected into the underground continuous wall template to form an underground continuous wall with the steel cage; ⑦ Before the underground continuous wall in step ⑥ solidifies and hardens, cement slurry is injected into the grouting pipe, the slurry at the angle between the flange plate and the web is squeezed out, and the gap around the grouting pipe is filled to form a cement slurry layer, so that the H-shaped steel and the underground continuous wall are tightly connected; ⑧ The underground continuous wall and cement slurry layer formed by grouting in step ⑦ are maintained, and the underground continuous wall template is removed after the maintenance is completed to obtain an underground continuous wall joint structure with better water-stopping effect. The steel cage is provided with beveled surfaces on both sides near one end of the H-shaped steel web, and the beveled surfaces are consistent with the inclination angle of the limiting inclined plate, and the end of the waterstop steel plate is in close contact with the beveled surfaces. The outer surface of the waterstop steel plate is coated with a galvanized layer.The angle between the limiting inclined plate and the flange plate of the H-beam is 45 degrees, the distance between the limiting inclined plate on the flange plate and the web is 5 cm, and the width of the gap between the two limiting inclined plates is 2-3 cm. Before inserting the grouting pipe in step ⑤, use high-pressure gas or high-pressure water to flush along the height direction in the space formed by the limiting inclined plate, web and flange plate to flush and clean the internal mud or slag. The grouting holes of the grouting pipe are evenly distributed along its length, and the aperture of the grouting holes is 2-5 mm. In steps ② and ③, when using a crawler crane with a brush to clean the mud on the outer side of the H-beam, the moving speed of the crawler crane is 0.5-1m / min to ensure that the mud is thoroughly cleaned. In step ⑥, when injecting concrete slurry into the underground continuous wall formwork, self-compacting concrete is used to reduce bubbles and voids in the concrete and improve the density of the underground continuous wall. In step ⑦, when injecting cement slurry into the grouting pipe, the pressure grouting method is adopted, and the grouting pressure is 0.2-0.5MPa to ensure that the cement slurry can fully fill the gap around the grouting pipe. In step ⑧, when curing the underground continuous wall and cement slurry layer formed by grouting, the curing time is 7-14 days and the curing temperature is 20-25℃ to ensure that the strength of the underground continuous wall and cement slurry layer meets the design requirements.

[0005] The positive effect of the present invention is that: the construction method for strengthening the water-stopping effect of underground continuous wall joints described in the present invention, after placing the underground continuous wall template in the foundation pit, the ground-connected wall frame unit at the starting end, the ground-connected wall frame units of several middle sections and the ground-connected wall frame unit at the terminal end are placed in the template in sequence, the ground-connected wall frame unit includes a steel cage and an H-shaped steel at the end, and a limiting inclined plate is arranged at the angle position of the outer side surface of the H-shaped steel. After cleaning the outer side surface of the H-shaped steel in the previous group of ground-connected wall frame units, the next group of ground-connected wall frame units are placed, and after the placement is completed, The grouting pipe and the water-stop steel plate are vertically inserted into the angle position in the limiting inclined plate, and concrete slurry is injected at the position of the steel cage to form an underground continuous wall. Before the underground continuous wall solidifies and hardens, cement slurry is injected into the grouting pipe to squeeze out and replace the mud at the angle position, thereby improving the mud cleaning quality and forming a dense connection between the H-shaped steel and the underground continuous wall to avoid the formation of structural defects such as leaks. At the same time, the setting of the water-stop steel plate can also extend the water seepage path and connect with the steel cage to form a corresponding water-proof structure. The above series of constructions can ensure the corresponding waterproof function of the ground-connected wall joint structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 This is a schematic diagram of the structure after step ① of the present invention is completed; Figure 2 This is a schematic diagram of the structure after step ② of the present invention is completed; Figure 3 This is a schematic diagram of the structure after step ③ of the present invention is completed; Figure 4 This is a schematic diagram of the structure after step ④ of the present invention is completed; Figure 5 This is a schematic diagram of the structure after step ⑤ of the present invention is completed; Figure 6 This is a schematic diagram of the structure after step ⑥ of the present invention is completed; Figure 7 This is a schematic diagram of the structure after step ⑦ of the present invention is completed; Figure 8 It is a schematic diagram of the structure after step ⑧ of the present invention is completed; Fig. 9 It is a schematic diagram of the joint water-stopping structure; Fig.10 It is a schematic diagram of the structure with a water-stop steel plate on the grouting pipe; Fig.11 yes Fig.10 Enlarged view of the AA section view. DETAILED DESCRIPTION

[0007] The construction method of the present invention for strengthening the waterproof effect of underground continuous wall joints is as follows: Figure 1-8 As shown, the following steps are included: ① Place several groups of underground continuous wall formworks 11 in the foundation pit near one side of the soil body, and place the ground-connected wall skeleton unit at the starting end in the underground continuous wall formwork 11, the ground-connected wall skeleton unit at the starting end includes a steel cage 3 and H-shaped steels 1 at both ends of the steel cage 3, wherein the H-shaped steel 1 is composed of flange plates on both sides and web plates between the flange plates, two corresponding limiting inclined plates 4 are arranged at the angle position between the flange plate and the web plate on the outside of the H-shaped steel 1, a gap is left between the two limiting inclined plates 4, a grouting pipe 5 is fixedly connected at the angle position between the flange plate and the web plate on the inside of the H-shaped steel 1, and the flange plate on one side of the grouting pipe 5 is fixedly connected to the steel cage 3; ② After the starting end ground-connected wall frame unit in step ① is placed, use a crawler crane with a brush to clean the mud on the outer side of the H-shaped steel 1 in the starting end ground-connected wall frame unit to prepare for the subsequent lowering of the middle part ground-connected wall frame unit; ③ After the cleaning operation in step ② is completed, the ground-connected wall skeleton unit of the middle section is placed into the underground continuous wall formwork 11, the ground-connected wall skeleton unit of the middle section includes a steel cage 3 and an H-shaped steel 1 at one end of the steel cage 3, the H-shaped steel 1 is far away from the ground-connected wall skeleton unit at the starting end, and the end of the steel cage 3 without the H-shaped steel 1 extends between the two flange plates of the H-shaped steel 1 in the ground-connected wall skeleton unit at the starting end, and the outer side surface of the H-shaped steel 1 in the ground-connected wall skeleton unit of the middle section is cleaned; ④ Repeat step ③ to complete the installation of multiple sets of intermediate ground-connected wall frame units, and install the terminal ground-connected wall frame unit at the end position, the terminal ground-connected wall frame unit only includes a steel cage 3, one end of the steel cage 3 extends between the two flange plates of the H-shaped steel 1 in the previous intermediate ground-connected wall frame unit, and the other end of the steel cage 3 cooperates with the H-shaped steel 1 pre-set in the underground continuous wall formwork 11; ⑤ After the ground-connected wall frame unit of the middle section and the ground-connected wall frame unit of the terminal end in step ④ are placed, a grouting pipe 5 is vertically inserted into the space formed by the limiting inclined plate 4, the flange plate and the web plate, wherein a grouting hole 6 is opened on the outer periphery of the grouting pipe 5, and a water-stop steel plate 8 is also connected to the grouting pipe 5, and the water-stop steel plate 8 is matched with the gap between the two limiting inclined plates 4, and the end of the water-stop steel plate 8 is in contact with the steel cage 3; ⑥ After the grouting pipe 5 in step ⑤ is installed, concrete slurry is injected into the underground continuous wall formwork 11 to form an underground continuous wall 2 with the steel cage 3; ⑦ Before the underground continuous wall 2 in step ⑥ solidifies and hardens, cement slurry is injected into the grouting pipe 5, the slurry at the angle between the flange plate and the web is squeezed out, and the gap around the grouting pipe 5 is filled to form a cement slurry layer 7, so that the H-shaped steel 1 and the underground continuous wall 2 are tightly connected and integrated; ⑧ Curing the underground continuous wall 2 and cement slurry layer 7 formed by grouting in step ⑦, and after the curing is completed, removing the underground continuous wall formwork 11 to obtain an underground continuous wall joint structure with a better water-stopping effect.

[0008] The H-shaped steel 1 is used as a joint structure between adjacent underground continuous walls 2. Two limiting inclined plates 4 are arranged at the angle position outside the H-shaped steel 1. The inner peripheral area of ​​the H-shaped steel 1 can be divided into a space for arranging the steel cage 3 outside the limiting inclined plates 4 and a space for arranging the grouting pipe 5 inside the limiting inclined plates 4. For the inner peripheral surface of the H-shaped steel outside the limiting inclined plates 4, a relatively clean cleaning can be achieved by using a brush. As for the internal space at the angle, cement slurry can be injected through the grouting pipe 5 to squeeze out the mud at the angle position of the flange plate and the web plate. Through the above construction operation, the mud on the inner peripheral surface of the H-shaped steel 1 can be cleaned more cleanly, and at the same time, the H-shaped steel 1 and the underground continuous wall 2 are tightly connected to form a whole, avoiding structural gaps caused by the presence of mud, and improving the waterproof performance of the overall ground-connected wall. For the H-shaped steel 1 on the inner side of the unit frame, since it is lowered together with the steel cage 3, the grouting pipe 5 on this side can be directly welded and fixed without the need for subsequent plug-in installation.

[0009] Injecting cement slurry before the underground continuous wall 2 hardens and solidifies is also beneficial for mixing the cement slurry layer 7 and the underground continuous wall 2. After hardening and curing, a ground-connected wall structure without gaps can be formed between them, thereby improving the waterproof performance of the ground-connected wall.

[0010] The arrangement of the limiting inclined plate 4 provides necessary positioning for the insertion of the grouting pipe 5 and the water-stopping steel plate 8. After the installation, the water-stopping steel plate 8 contacts the end face of the steel cage 3. In this way, on the internal skeleton structure of the integral ground-connected wall, the water-stopping steel plate 8 can form a partition to block water leakage, and at the same time, it also extends the seepage path of the leaking water, greatly reducing the occurrence of water leakage.

[0011] The flange plate with the grouting pipe 5 fixedly connected to one side is fixedly connected to the steel cage 3, and the flange plate with the grouting pipe 5 inserted on one side is connected to the steel cage 3 through concrete. The above structure is set up so that one side of the H-shaped steel 1 is connected to the steel cage 3, and the H-shaped steel 1 and the steel cage 3 can be lowered into the forming groove as a continuous wall frame unit. The grouting pipe 5 on the inside of the frame unit can be directly welded and connected, and the side of the H-shaped steel 1 on the outside of the frame unit requires subsequent wall brushing operations before the subsequent frame unit can be lowered. In order to make the cleaning between the outer flange plate and the web plate cleaner, a limiting inclined plate 4 needs to be set here, and the grouting pipe 5 is inserted and installed in coordination.

[0012] The ground-connected wall frame unit at the starting end, several groups of ground-connected wall frame units in the middle sections, and the ground-connected wall frame unit at the ending end are installed in sequence, and the outer side of the H-shaped steel 1 in the previous group of frame units is washed before installation. After the installation is completed, cement slurry is injected into the grouting pipe 5, which can effectively improve the cleanliness of the dirt cleaning at the joint position of the ground-connected wall and ensure the molding integrity and waterproof performance of the underground continuous wall 2.

[0013] Furthermore, in order to make the steel cage 3 fit the H-shaped steel 1 with the limiting inclined plate 4, as shown in FIG. Fig. 9 As shown, the steel cage 3 is provided with chamfered surfaces 9 on both sides of one end of the web of the H-shaped steel 1, and the chamfered surfaces 9 are consistent with the inclination angle of the limiting inclined plate 4, and the end of the water stop steel plate 8 is in close contact with the chamfered surface 9. The above structure can provide a certain position distance reference when the steel cage 3 is lowered, and the limiting inclined plate 4 and the chamfered surface 9 arranged in parallel can also avoid collision interference caused by lowering to a certain extent. After the steel cage 3 is placed in the subsequent skeleton unit, it is also convenient to adjust the position of the steel cage 3 in the template, thereby ensuring that the steel cage 3 will be located in the middle of the overall underground continuous wall 2, providing the strength of the ground-connected wall.

[0014] Furthermore, if Fig.10 and Fig.11 As shown, in order to improve the durability and anti-corrosion performance of the water-stop steel plate 8, a galvanized layer 10 is coated on the outer surface of the water-stop steel plate 8.

[0015] Furthermore, in order to facilitate welding and fixing the limiting inclined plate 4 on the H-shaped steel 1, the angle between the limiting inclined plate 4 and the flange plate of the H-shaped steel 1 is 45 degrees, the limiting inclined plate 4 on the flange plate is 5 cm away from the web plate, the gap width between the two limiting inclined plates 4 is 2-3 cm, and the waterstop steel plate 8 with a galvanized layer 10 is adapted to the gap between the limiting inclined plates 4.

[0016] Furthermore, in order to clean the angle positions on both sides of the H-shaped steel 1 in advance before the grouting pipe 5 is installed, before the grouting pipe 5 is inserted in step ⑤, high-pressure gas or high-pressure water is used to flush the space formed by the limiting inclined plate 4, the web plate, and the flange plate along the height direction, and then the grouting pipe 5 is inserted, and concrete is poured to form an underground continuous wall. Before the concrete is completely solidified, cement mortar is injected into the grouting pipe 5 to squeeze out the residual mud or slag inside, and to seal the seepage channel of the internal space, thereby playing a corresponding plugging function and realizing the effects of compaction, compaction, replacement and reinforcement in the space formed by the limiting inclined plate 4, the web plate, and the flange plate.

[0017] Furthermore, the grouting holes 6 of the grouting pipe 5 are evenly distributed along its length direction, and the diameter of the grouting holes 6 is 2-5 mm.

[0018] Furthermore, in step ② and step ③, when the outer side of the H-beam 1 is cleaned of mud using a crawler crane with a brush, the moving speed of the crawler crane is 0.5-1 m / min to ensure that the mud is thoroughly cleaned.

[0019] Furthermore, in step ⑥, when injecting concrete slurry into the underground continuous wall formwork 11, self-compacting concrete is used to reduce bubbles and voids in the concrete and improve the compactness of the underground continuous wall 2.

[0020] Furthermore, in step ⑦, when injecting cement slurry into the grouting pipe 5 , a pressure grouting method is adopted, and the grouting pressure is 0.2-0.5 MPa to ensure that the cement slurry can fully fill the gaps around the grouting pipe 5 .

[0021] Furthermore, in step ⑧, when curing the underground continuous wall 2 and cement slurry layer 7 formed by grouting, the curing time is 7-14 days and the curing temperature is 20-25°C to ensure that the strength of the underground continuous wall 2 and the cement slurry layer 7 meets the design requirements.

[0022] The technical solution of the present invention is not limited to the scope of the embodiments described in the present invention. The technical contents not described in detail in the present invention are all well-known technologies.

Claims

1. A construction method for strengthening the water-stopping effect of underground continuous wall joints, characterized in that: The method comprises the following steps: ① placing a plurality of sets of underground continuous wall formworks (11) in a foundation pit close to one side of the soil body, and placing a ground-connected wall frame unit at the starting end in the underground continuous wall formworks (11), wherein the ground-connected wall frame unit at the starting end comprises a steel cage (3) and H-shaped steels (1) at both ends of the steel cage (3), wherein the H-shaped steel (1) is composed of flange plates on both sides and a web between the flange plates, two corresponding limiting inclined plates (4) are arranged at the angle between the flange plates and the web of the outer side of the H-shaped steel (1), a gap is left between the two limiting inclined plates (4), a grouting pipe (5) is fixedly connected at the angle between the flange plates and the web of the inner side of the H-shaped steel (1), and the flange plate on one side of the grouting pipe (5) is fixedly connected to the steel cage (3); ② After the placement of the starting end ground tethered wall frame unit in step ① is completed, use a crawler crane with a brush to clean the mud on the outer side of the H-shaped steel (1) in the starting end ground tethered wall frame unit to prepare for the subsequent lowering of the middle part ground tethered wall frame unit; ③ After the cleaning operation in step ② is completed, the middle section of the ground-connected wall frame unit is placed into the underground continuous wall formwork (11), the middle section of the ground-connected wall frame unit comprising a steel cage (3) and an H-shaped steel (1) at one end of the steel cage (3), the H-shaped steel (1) being away from the ground-connected wall frame unit at the starting end, the end of the steel cage (3) not provided with the H-shaped steel (1) extending between the two flange plates of the H-shaped steel (1) in the ground-connected wall frame unit at the starting end, and the outer side surface of the H-shaped steel (1) in the middle section of the ground-connected wall frame unit is cleaned; ④ Repeat step ③ to complete the installation of multiple sets of intermediate ground-connected wall frame units, and install the terminal ground-connected wall frame unit at the end position, wherein the terminal ground-connected wall frame unit only includes a steel cage (3), one end of the steel cage (3) extends between the two flange plates of the H-shaped steel (1) in the previous intermediate ground-connected wall frame unit, and the other end of the steel cage (3) cooperates with the H-shaped steel (1) pre-set in the underground continuous wall formwork (11); ⑤ After the ground-connected wall frame unit of the middle section and the ground-connected wall frame unit of the terminal end in step ④ are placed, a grouting pipe (5) is vertically inserted into the space formed by the limiting inclined plate (4), the flange plate and the web plate, wherein a grouting hole (6) is opened on the outer periphery of the grouting pipe (5), and a water-stopping steel plate (8) is connected to the grouting pipe (5), the water-stopping steel plate (8) is matched with the gap between the two limiting inclined plates (4), and the end of the water-stopping steel plate (8) is in contact with the steel cage (3); ⑥ After the grouting pipe (5) in step ⑤ is installed, concrete slurry is injected into the underground continuous wall formwork (11) to form an underground continuous wall (2) with the steel cage (3); ⑦ Before the underground continuous wall (2) in step ⑥ solidifies and hardens, cement slurry is injected into the grouting pipe (5), the slurry at the angle between the flange plate and the web plate is squeezed out, and the gap around the grouting pipe (5) is filled to form a cement slurry layer (7), so that the H-shaped steel (1) and the underground continuous wall (2) are tightly connected and integrated; ⑧ Curing the underground continuous wall (2) and cement slurry layer (7) formed by grouting in step ⑦, and after the curing is completed, removing the underground continuous wall template (11), thereby obtaining an underground continuous wall joint structure with a better water-stopping effect.

2. A construction method for strengthening the water-stopping effect of underground continuous wall joints according to claim 1, characterized in that: The steel cage (3) is provided with chamfered surfaces (9) on both sides of one end of the web of the H-shaped steel (1), the chamfered surfaces (9) are consistent with the inclination angle of the limiting inclined plate (4), and the end of the water stop steel plate (8) is in close contact with the chamfered surface (9).

3. A construction method for strengthening the waterproof effect of underground continuous wall joints according to claim 1, characterized in that: The outer surface of the water-stop steel plate (8) is coated with a galvanized layer (10).

4. A construction method for strengthening the waterproof effect of underground continuous wall joints according to claim 1, characterized in that: The angle between the limiting inclined plate (4) and the flange plate of the H-shaped steel (1) is 45 degrees, the distance between the limiting inclined plate (4) on the flange plate and the web plate is 5 cm, and the width of the gap between the two limiting inclined plates (4) is 2-3 cm.

5. A construction method for strengthening the waterproof effect of underground continuous wall joints according to claim 1, characterized in that: Before inserting the grouting pipe (5) in step ⑤, high-pressure gas or high-pressure water is used to flush the space formed by the limiting inclined plate (4), the web plate, and the flange plate along the height direction to flush and clean the mud or residual slag inside.

6. A construction method for strengthening the waterproof effect of underground continuous wall joints according to claim 1, characterized in that: The grouting holes (6) of the grouting pipe (5) are evenly distributed along its length direction, and the diameter of the grouting holes (6) is 2-5 mm.

7. A construction method for strengthening the waterproof effect of underground continuous wall joints according to claim 1, characterized in that: In step ② and step ③, when the outer side of the H-shaped steel (1) is cleaned of mud using a crawler crane with a brush, the moving speed of the crawler crane is 0.5-1 m / min to ensure that the mud is thoroughly cleaned.

8. A construction method for strengthening the waterproof effect of underground continuous wall joints according to claim 1, characterized in that: In step ⑥, when injecting concrete slurry into the underground continuous wall formwork (11), self-compacting concrete is used to reduce bubbles and voids in the concrete and improve the compactness of the underground continuous wall (2).

9. A construction method for strengthening the waterproof effect of underground continuous wall joints according to claim 1, characterized in that: In step ⑦, when injecting cement slurry into the grouting pipe (5), a pressure grouting method is adopted, and the grouting pressure is 0.2-0.5 MPa, so as to ensure that the cement slurry can fully fill the gaps around the grouting pipe (5).

10. A construction method for strengthening the waterproof effect of underground continuous wall joints according to claim 1, characterized in that: In step ⑧, the underground continuous wall (2) and the cement slurry layer (7) formed by grouting are cured for 7-14 days at a curing temperature of 20-25° C., so as to ensure that the strength of the underground continuous wall (2) and the cement slurry layer (7) meets the design requirements.

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