Quick plugging system for leakage of waterproof curtain of deep foundation pit in water-rich silt layer and construction method

Abstract

The invention relates to a water-rich silt layer deep foundation pit waterproof curtain leakage rapid plugging system and a construction method, through a foundation pit filler isolation water diversion pressure relief plugging technology, plugging is carried out through fillers such as cotton fibers, then water diversion pressure relief flow guiding is carried out through a flow guiding device, the flow guiding device is convenient to manufacture, construction steps are simple, and the construction cost is low. Quick plugging of leakage points is realized, and the construction efficiency is improved; by means of the section steel support flexible cable net water injection bag rapid back pressure technology, when water seepage occurs around the foundation pit, water is injected into the flexible cable net water injection bag through a water injection device, the bag expands to generate reverse pressure, the wall of the foundation pit is pressed, a leakage channel is rapidly blocked, water seepage is prevented, and construction safety is guaranteed. Meanwhile, the water injection rate and pressure are flexibly controlled through the water injection system, and the requirements of different foundation pit environments can be met; through the back pressure technology after the built-in gravel perforated drainage pipe blind ditch, the underground water level in the foundation pit is effectively controlled, and the foundation pit leakage phenomenon is reduced.

Description

Technical Field

[0001] The invention belongs to the field of foundation pit plugging, and in particular relates to a rapid plugging system for water-stop curtain leakage in a deep foundation pit in a water-rich silt sand layer and a construction method. Background Art

[0002] With the continuous advancement of urbanization, deep foundation pit projects have been widely used in underground buildings, subways, tunnels and other fields. However, during the construction of deep foundation pits, due to the high groundwater level and complex geological conditions, especially in areas with poor hydrogeological conditions such as water-rich silt sand layers, the problem of foundation pit water stopping has always been a difficulty in construction. Although traditional water stopping methods such as concrete anti-seepage walls and steel sheet pile water stopping can prevent water leakage to a certain extent, the waterproofing effect is often unsatisfactory in areas with soft soil and strong permeability such as water-rich silt sand layers, especially during the excavation of foundation pits, due to soil deformation or improper construction, the water stopping curtain is easily ineffective, causing leakage.

[0003] Existing water-stopping technologies usually rely on the continuity and stability of waterproof materials. However, in deep foundation pit construction, once leakage occurs, it is difficult to deal with and the construction period is tight. Therefore, there is an urgent need for a new type of sealing system that can quickly solve leakage, is easy to construct and has a good water-stopping effect. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies in the prior art and to provide a rapid leakage plugging system and construction method for a water-rich silt sand layer deep foundation pit water-stop curtain.

[0005] The construction method of the water-rich silt sand layer deep foundation pit water-stop curtain leakage rapid plugging system comprises the following specific steps: Step 1: Use cotton wool to seal the seepage holes in the foundation pit, install a diversion device to divert the leaking water to the steel pipe well, and the steel pipe well diverts the water to the external drainage ditch through a submersible pump; Step 2: grouting and sealing the water-stop curtain outside the foundation pit; Step 3: Install a water injection bag on the inner side of the foundation pit support structure; fill the water injection bag with water to seal the water seepage channel; Step 4: Set up transverse drainage pipes and water collection tanks at the inner support to drain the leaking water at the bottom of the foundation pit to the water collection ditch and water collection tank outside the foundation pit; Step 5: Lay a drainage blind ditch inside the foundation pit, and connect the drainage blind ditch inside the foundation pit and the steel pipe well outside the foundation pit through a drainage pipe.

[0006] Preferably, in step one, after leakage of the foundation pit, the hole is cleaned, sealed with cotton wool filler, and an excavator is used to assist manual work, and a diversion device is installed at the hole of the seepage hole, the diversion device includes a galvanized pipe, a lower flexible pipe and a stop ball valve, and hemp wire is wrapped around the upper part of the galvanized pipe to facilitate its insertion into the hole; the diversion device diverts the leaking water to the steel pipe well area, and a submersible pump is provided on the upper part of the steel pipe well to divert the water to the external drainage ditch area; before installing the diversion device, remove the lower flexible pipe and the stop ball valve, and place wooden boards on the galvanized pipe.

[0007] Preferably, during the foundation pit construction, a steel support is installed on the inner side of the foundation pit support structure, and a flexible cable net and a water injection bag are arranged on the inner side of the steel support; in step three, the surface drainage ditch is connected to the water injection bag through a water injection pipe, and water is injected into the water injection bag through a valve; when the water injection bag is filled with water, the expansion pressure generated acts in reverse on the foundation pit wall, closing the seepage channel, thereby achieving the purpose of water stopping.

[0008] Preferably, in step three, the steel support is a supporting structure, which is fixed to the flexible cable net and the water-filled bladder through connectors; the connectors are used to firmly fix the flexible cable net and the water-filled bladder on the steel support.

[0009] Preferably, in step four, a steel drainage riser is arranged on the foundation pit retaining piles, a transverse drainage pipe is arranged at the support in the foundation pit, and a water collecting tank is arranged on the side of the support in the foundation pit away from the foundation pit retaining piles. The transverse drainage pipe uses a submersible pump to drain the leaked water at the bottom of the foundation pit to the water collecting ditch and water collecting tank outside the foundation pit; two steel water collecting tank hanging ears are welded on both sides of the water collecting tank, and the water collecting tank is placed on the support in the foundation pit through the water collecting tank hanging ears.

[0010] Preferably, in step two, the positions of grouting holes are set according to the leakage positions of the water-stop curtain, and the grouting holes are arranged in a plum blossom shape; grouting is carried out using a vertical grouting pipe, and a drill rig with a sensor is used to adjust the verticality of the borehole in real time during the drilling of the grouting holes; a grouting pump, a hydraulic pump and a mixer are arranged outside the foundation pit to carry out grouting operations, and cement sealing is performed after the grouting is completed.

[0011] Preferably, in step five, a foundation pit trench is excavated at the designed location of the drainage blind ditch, medium sand is laid at the bottom and both sides of the trench to form a medium sand filter layer, a permeable geotextile layer is laid on the medium sand filter layer, and graded crushed stone is laid on the permeable geotextile layer as a drainage layer; a drainage pipe is laid on the permeable geotextile layer, the drainage pipe connects the drainage blind ditch in the foundation pit and the steel pipe well outside the foundation pit, and a back pressure valve is provided on the drainage pipe.

[0012] Preferably, there is a step six after step five, in which a number of steel pipe support piles are driven around the foundation pit, and a layer of waterproof sealing material is sprayed on the inner wall of the steel pipe support piles; the outer wall of the steel pipe support piles is wrapped with a concrete layer reinforced with a steel mesh; a water stop plate is installed on the top of the steel pipe support piles; a drainage pipe is set up to connect multiple steel pipe support piles to form a complete drainage system, which guides the water flow inside and outside the foundation pit to the external drainage system; the drainage pipe includes a longitudinal drainage pipe and a transverse drainage pipe, the longitudinal drainage pipe is arranged along the longitudinal direction of the foundation pit, and the transverse drainage pipe connects multiple longitudinal drainage pipes.

[0013] The water-rich silt sand layer deep foundation pit water-stop curtain leakage rapid plugging system is constructed by any of the above methods The beneficial effects of the present invention are: 1) The present invention uses the technology of isolating, diverting, and releasing pressure to seal the foundation pit through filling materials. It first seals the foundation pit through filling materials such as cotton wool, and then uses a diversion device to divert water, release pressure, and divert the foundation pit. The diversion device is easy to manufacture and has simple construction steps, which can achieve rapid sealing of leakage points and improve construction efficiency.

[0014] 2) The present invention uses the steel support flexible cable net water injection bag rapid back pressure technology. When water seepage occurs around the foundation pit, water is injected into the flexible cable net water injection bag through the water injection device. The bag expands to generate reverse pressure, compressing the foundation pit wall, quickly blocking the leakage channel to prevent water seepage and ensure construction safety. At the same time, the water injection system can flexibly control the water injection volume and pressure to meet the needs of different foundation pit environments.

[0015] 3) The present invention adopts the back-pressure technology after the built-in gravel perforated drainage pipe blind ditch, arranges the gravel perforated drainage pipe blind ditch inside the foundation pit, uses the drainage pipe in the blind ditch to drain the water inside the foundation pit to the outside of the foundation pit, and at the same time, the drainage pipe is provided with a back-pressure valve to prevent the water outside the foundation pit from entering the inside of the foundation pit, effectively controls the groundwater level in the foundation pit, and reduces the leakage of the foundation pit.

[0016] 4) The present invention uses the drainage steel pipe support pile stabilization reinforcement technology. By installing a number of steel pipe support piles around the foundation pit and spraying waterproof sealing materials inside the steel pipe, the external reinforcement protective layer can effectively prevent water leakage and enhance the stability of the pile body. The structural coordination inside and outside the steel pipe support pile realizes the waterproof, drainage and reinforcement functions of the foundation pit. The design of the drainage pipe system can effectively guide the water flow to the external drainage system, maintain the balance of the water level inside and outside the foundation pit, and avoid leakage of the foundation pit due to excessively high water levels. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the drainage of foundation pit leakage filling material; Figure 2 is a schematic diagram of the drainage device; Figure 3 This is the grouting and plugging diagram of the water-stop curtain outside the pit; Figure 4 This is a schematic diagram of the rapid back pressure of the water-filled bag of the steel support flexible cable net; Figure 5 This is a schematic diagram of the rapid drainage of the steel plate drainage trough supported and hung inside the retaining pile; Figure 6 It is a schematic diagram of back pressure after blind ditch of built-in gravel perforated drainage pipe; Figure 7 It is a schematic diagram of the stabilization and reinforcement of drainage steel pipe support piles.

[0018] Explanation of reference numerals: 1-shear wall; 2-structural side wall; 3-leakage area; 4-cotton plugging material; 5-steel pipe well; 6-graded crushed stone; 7-submersible pump; 8-bottom plate; 9-flow guide device; 10-flow guide pipe; 11-stop ball valve; 12-installation handle; 13-flexible; 14-galvanized pipe; 15-banyan pile; 16-bored pile; 17-water-stop curtain; 18-cement seal; 19-grouting pipe; 20-grouting pump; 21-hydraulic pump; 22-mixer; 23-connector; 24-water injection bag; 25-control valve ; 26-water collection ditch; 27-flexible cable net; 28-steel support; 29-cement mixing pile; 30-steel drainage riser; 31-guard pile; 32-support inside the foundation pit; 33-lateral drainage pipe; 34-water collection tank; 35-medium sand filter layer; 36-concrete cover; 37-permeable geotextile layer; 38-drainage blind ditch; 39-drainage pipe; 40-back pressure valve; 41-steel pipe support pile; 42-rubber water stop plate; 43-reinforced concrete coating; 44-waterproof coating; 45-longitudinal drainage pipe; 46-lateral drainage pipe. DETAILED DESCRIPTION

[0019] The present invention is further described below in conjunction with embodiments. The description of the following embodiments is only used to help understand the present invention. It should be noted that for ordinary persons in the art, without departing from the principle of the present invention, the present invention can also be modified in some ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

[0020] Embodiment 1 As an example, Figures 1 to 7 As shown, the construction method of the water-rich silt sand layer deep foundation pit water-stop curtain leakage rapid plugging system comprises the following steps: Step 1: The seepage holes in the foundation pit are sealed with cotton wool fillers 4, and a diversion device 9 is installed to divert the leaking water to the steel pipe well 5. The steel pipe well 5 diverts the water to the external drainage ditch through a submersible pump 7; Step 2: Grout the water-stop curtain outside the foundation pit to seal it; set the grouting hole position according to the leakage position of the water-stop curtain, and arrange the grouting holes in a plum blossom shape. Use a vertical grouting pipe 1 for grouting, and use a drill with a sensor to adjust the verticality of the hole in real time during the drilling of the grouting hole. A grouting pump 20, a hydraulic pump 21, and a mixer 22 are arranged outside the foundation pit to carry out grouting operations. After the grouting is completed, cement sealing 18 is performed to effectively seal the leakage points of the foundation pit; Step 3: Install a water injection bag 24 on the inner side of the foundation pit support structure; fill the water injection bag 24 with water to seal the water seepage channel; Step 4: Set up a transverse drainage pipe 33 and a water collection tank 34 at the inner support 32 to drain the leaking water at the bottom of the foundation pit to the water collection ditch 26 and the water collection tank 34 outside the foundation pit; Step 5: lay out a blind drainage ditch 38 inside the foundation pit, and connect the blind drainage ditch 38 inside the foundation pit and the steel pipe well 5 outside the foundation pit through a drainage pipe 39.

[0021] Embodiment 2 As another embodiment, this embodiment 2 proposes, on the basis of the embodiment 1, a more specific construction method of a rapid leakage plugging system for a water-rich silty sand layer deep foundation pit water-stop curtain: like Figure 4 As shown, during the foundation pit construction, a steel bracket 28 is installed on the inner side of the foundation pit support structure, and a flexible cable net 27 water-filled bag 24 is arranged on the inner side of the bracket. The steel bracket 28 is a supporting structure, and is fixed to the flexible cable net 27 water-filled bag 24 through a connector 23; the connector 23 is used to firmly fix the flexible cable net water-filled bag on the steel bracket to ensure that it is stable and does not shift when the back pressure is applied. The flexible cable net 27 water-filled bag 24 is made of water-resistant material, has flexibility and elasticity, and is installed on the inner side of the foundation pit support structure.

[0022] In step one, the foundation pit filling material is used to isolate the water diversion and pressure relief plugging technology: Figure 1 and Figure 2 As shown, after the foundation pit leaks, the hole is cleaned, and cotton wool filler 4 is used to seal it, and mechanical equipment is used to compact the hole filler such as cotton wool. An excavator is used to assist manual work, and a diversion device is installed at the hole of the seepage hole. Hemp silk is wrapped around the upper part of the galvanized pipe 14 to make it easy to insert into the hole. The diversion device diverts the leaking water to the steel pipe well 5 area. A submersible pump 7 is installed on the upper part of the steel pipe well 5 to divert the water to the external drainage ditch area. The diversion device uses a DN600 model and is made of high-strength PVC pipe. Before installing the diversion device, remove the lower flexible 13 and the stop ball valve 11, and place a 50cm thick wooden board on the galvanized pipe 14 to prevent damage during installation.

[0023] In step three, if Figure 4As shown, the surface water collection ditch 26 is connected to the water injection bag through a water injection pipe, and water is injected into the bag 24 through a valve 25 when needed. When the bag 24 is filled with water, the expansion pressure generated will quickly act in reverse on the foundation pit wall, closing the seepage channel, thereby achieving the purpose of water stopping.

[0024] It should be noted that the parts in this embodiment that are the same or similar to those in the first embodiment can be referenced to each other and will not be described in detail in this application.

[0025] Embodiment 3 As another embodiment, this embodiment 3 proposes, on the basis of the embodiment 2, a more specific construction method of a rapid leakage plugging system for a water-rich silty sand layer deep foundation pit water-stop curtain: Step 4 involves the rapid drainage technology of the steel plate drainage trough supported and hung inside the retaining pile: Figure 5 As shown, a steel drainage riser 30 is set on the foundation pit retaining pile 31, a transverse drainage pipe 33 is set at the second and third inner supports 32 of the foundation pit, and a water collecting tank 34 is set on the side of the inner support away from the retaining pile. Two steel water collecting tank hanging ears are welded on both sides of the water collecting tank 34, and the water collecting tank 34 is placed on the inner support beam through the water collecting tank hanging ears. The submersible pump 7 is used to guide the leakage water at the bottom of the foundation pit to the external drainage ditch and the inner support water collecting tank 34, which quickly reduces the leakage of the foundation pit and has a good water stopping effect; Step 5 involves the back pressure technology behind the blind ditch of the built-in gravel perforated drainage pipe: Figure 6 As shown, a blind drainage ditch 38 is arranged inside the foundation pit. A foundation pit trench is excavated, and medium sand is laid at the bottom and both sides of the trench to form a medium sand filter layer 35. A permeable geotextile layer 37 is laid on the medium sand filter layer 35, and graded crushed stone 6 is laid on the geotextile layer 37 as a drainage layer. A drainage pipe 3 is laid on the geotextile layer, and the pipe material is usually a high-strength PVC pipe. The pipe connects the blind drainage ditch 38 in the foundation pit with the water collection well 26 outside the foundation pit. A back-pressure valve 40 is provided on the drainage pipe 38 to effectively lower the groundwater level inside the foundation pit and reduce leakage in the foundation pit; Step 6 involves the stabilization and reinforcement technology of drainage steel pipe support piles: Figure 7As shown, several steel pipe support piles 41 are driven around the foundation pit, and a layer of waterproof sealing material is sprayed on the inner wall of the steel pipe support pile 41. The waterproof sealing material is a high-performance polyurethane waterproof coating with high adhesion and water resistance. The coating thickness of the waterproof sealing material is 1mm to 3mm, which can effectively resist water seepage and water pressure. The outer wall of the steel pipe support pile is wrapped with a concrete layer 43 reinforced with a steel mesh, which plays a role in reinforcing the pile body and enhancing the waterproof performance. A water stop plate 42 is installed on the top of the steel pipe support pile to prevent moisture from penetrating through the pile top; a plurality of steel pipe support piles 41 are connected by setting a water flow drainage pipeline, and the drainage pipeline includes a longitudinal drainage pipe 45 and a transverse drainage pipe 46. The longitudinal drainage pipe 45 is arranged along the depth direction of the foundation pit, and the transverse drainage pipe 46 connects multiple longitudinal drainage pipes to ensure that the water flow inside and outside the foundation pit can be discharged quickly and effectively.

[0026] It should be noted that the parts in this embodiment that are the same or similar to those in the second embodiment can be referenced to each other and will not be described in detail in this application.

[0027] Embodiment 4 As another embodiment, this embodiment 4 proposes, based on the embodiment 3, a rapid leakage plugging system of a water-rich silty sand layer deep foundation pit water-stopping curtain: like Figure 1 , Figure 2 As shown, when the foundation pit leaks near the foundation pit shear wall, the foundation pit leaks through fillers 4 such as cotton wool, and the outside of the foundation pit is connected to a diversion device 9. The diversion device 9 uses a DN600 high-strength pipe as a diversion pipe 10, which is connected to the leakage point through a galvanized pipe 14, and the diversion device 9 is filled with graded crushed stone 6. The foundation pit leaks through the diversion device 9 to the steel pipe well 5 area, and a submersible pump 7 is arranged on the upper part of the foundation pit bottom plate. The seepage water in the steel pipe well 5 is discharged to the outside area of ​​the foundation pit through the submersible pump 7, and the foundation pit leaks quickly, with a good drainage effect.

[0028] like Figure 3 As shown, when the foundation pit water-stop curtain leaks, grouting outside the pit is used to seal it. The grouting holes are located near the water-stop curtain and are arranged in a plum blossom shape. The verticality of the foundation pit grouting holes is strictly controlled when drilling. Grouting of the foundation pit is carried out using a grouting pump 20, a hydraulic pump 21 and a mixer 22. After grouting, cement sealing 18 is used to seal it to ensure airtightness.

[0029] like Figure 4As shown, a steel support 28 is arranged near the cement mixing pile of the foundation pit, a flexible cable net 27 is arranged inside the steel support 28, and a water injection bag 24 is installed on the flexible cable net 27. The water injection bag 24 is arranged in a separated manner and fixed on the flexible cable net 27 through a connector 23. The water injection bag 24 is connected to a water injection pipeline, which is connected to an external water collection ditch 26, and the water injection is controlled by a control valve 25. When the foundation pit leaks, the water injection valve 25 is opened, and the water injection bag 24 expands rapidly to press the foundation pit wall and close the seepage pipeline.

[0030] like Figure 5 As shown, a steel drainage riser 30 is arranged near the foundation pit retaining piles, and the steel drainage riser 30 penetrates into the bottom of the foundation pit. A drainage pipe 33 is added to the support inside the foundation pit. A water collecting tank 34 is arranged on the side of the support inside the foundation pit away from the retaining piles. When the bottom of the foundation pit leaks, the ground submersible pump 7 is started to drain the leaked water at the bottom of the foundation pit to the external water collecting ditch 26 and the internal support water collecting tank, thereby reducing the damage caused by the leakage of the foundation pit.

[0031] like Figure 6 As shown, a blind drainage ditch 38 is arranged inside the foundation pit, the outside of the blind drainage ditch 38 is a medium sand filter layer 35, the inside is a permeable geotechnical layer 37 and a graded crushed stone 6 water collection layer, and a concrete cover plate 36 is added to the upper part of the blind drainage ditch 38 to ensure that the blind drainage ditch does not float. A drainage pipe 39 is arranged inside the graded crushed stone 6 water collection layer, and the pipe is connected to the external water collection well 26. A back pressure valve 40 is arranged on the drainage pipe 39 to ensure that water can only flow from the inside to the external water collection well, control the groundwater level inside the foundation pit, and prevent the water level from being too high to cause leakage in the foundation pit.

[0032] like Figure 7 As shown, the foundation pit is supported by steel pipe support piles 41, and the steel pipe support piles 41 are wrapped with a mesh reinforced concrete coating 43 to reinforce the support piles. A waterproof coating 44 is used inside, and a rubber water stop plate 42 is arranged on the top. Each support pile is connected by a longitudinal drainage pipe 45 and a transverse drainage pipe 46, and the bottom seepage water is led to the external water collection ditch 26 by a submersible pump 7 to reduce the damage caused by the leakage of the foundation pit.

[0033] It should be noted that the parts in this embodiment that are the same or similar to those in Embodiment 3 can be referenced to each other and will not be described in detail in this application.

[0034] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

Claims

1. A construction method for a rapid leakage plugging system of a water-stop curtain for a deep foundation pit in a water-rich silt sand layer, characterized in that: The specific steps include: Step 1: Use cotton wool to seal the seepage holes in the foundation pit, install a diversion device to divert the leaking water to the steel pipe well, and the steel pipe well diverts the water to the external drainage ditch through a submersible pump; Step 2: grouting and sealing the water-stop curtain outside the foundation pit; Step 3: Install a water injection bag on the inner side of the foundation pit support structure; fill the water injection bag with water to seal the water seepage channel; Step 4: Set up transverse drainage pipes and water collection tanks at the inner support to drain the leaking water at the bottom of the foundation pit to the water collection ditch and water collection tank outside the foundation pit; Step 5: Lay a drainage blind ditch inside the foundation pit, and connect the drainage blind ditch inside the foundation pit and the steel pipe well outside the foundation pit through a drainage pipe.

2. The construction method of a water-rich silt sand layer deep foundation pit water-stop curtain leakage rapid plugging system according to claim 1 is characterized in that: In step one, the hole is cleaned after leakage in the foundation pit, and it is sealed with cotton wool filler. An excavator is used to assist manual work, and a diversion device is installed at the hole of the seepage hole. The diversion device includes a galvanized pipe, a lower flexible pipe and a stop ball valve. Hemp wire is wrapped around the upper part of the galvanized pipe to facilitate its insertion into the hole. The diversion device diverts the leaking water to the steel pipe well area. A submersible pump is installed on the upper part of the steel pipe well to divert the water to the external drainage ditch area. Before installing the diversion device, remove the lower flexible pipe and the stop ball valve, and place wooden boards on the galvanized pipe.

3. The construction method of a water-rich silt sand layer deep foundation pit water-stop curtain leakage rapid plugging system according to claim 1, characterized in that: During foundation pit construction, a steel support is installed on the inner side of the foundation pit support structure, and a flexible cable net and a water injection bag are arranged on the inner side of the steel support; in step three, the surface drainage ditch is connected to the water injection bag through a water injection pipe, and water is injected into the water injection bag through a valve; when the water injection bag is filled with water, the expansion pressure generated acts in reverse on the foundation pit wall, closing the seepage channel, thereby achieving the purpose of water stopping.

4. The construction method of a water-rich silt sand layer deep foundation pit water-stop curtain leakage rapid plugging system according to claim 3, characterized in that: In step three, the steel support is a supporting structure, which is fixed to the flexible cable net and the water-filled bladder through connectors; the connectors are used to firmly fix the flexible cable net and the water-filled bladder on the steel support.

5. The construction method of a water-rich silt sand layer deep foundation pit water-stop curtain leakage rapid plugging system according to claim 1, characterized in that: In step four, a steel drainage riser is installed on the foundation pit retaining piles, a transverse drainage pipe is installed at the support inside the foundation pit, and a water collecting tank is installed on the side of the support inside the foundation pit away from the foundation pit retaining piles. The transverse drainage pipe uses a submersible pump to drain the leaked water at the bottom of the foundation pit to the water collecting ditch and water collecting tank outside the foundation pit; two steel water collecting tank hanging ears are welded on both sides of the water collecting tank, and the water collecting tank is placed on the support inside the foundation pit through the water collecting tank hanging ears.

6. The construction method of a water-rich silt sand layer deep foundation pit water-stop curtain leakage rapid plugging system according to claim 1, characterized in that: In step two, the positions of grouting holes are set according to the leakage positions of the water-stop curtain, and the grouting holes are arranged in a plum blossom shape; grouting is carried out using a vertical grouting pipe, and a drill rig with a sensor is used to adjust the verticality of the borehole in real time during the drilling process of the grouting holes; a grouting pump, a hydraulic pump and a mixer are arranged outside the foundation pit for grouting operations, and cement sealing is performed after the grouting is completed.

7. The construction method of a water-rich silt sand layer deep foundation pit water-stop curtain leakage rapid plugging system according to claim 1, characterized in that: In step five, a foundation pit trench is excavated at the designed location of the drainage blind ditch, medium sand is laid at the bottom and both sides of the trench to form a medium sand filter layer, a permeable geotextile layer is laid on the medium sand filter layer, and graded crushed stone is laid on the permeable geotextile layer as a drainage layer; a drainage pipe is laid on the permeable geotextile layer, the drainage pipe connects the drainage blind ditch in the foundation pit and the steel pipe well outside the foundation pit, and a back pressure valve is provided on the drainage pipe.

8. The construction method of a water-rich silt sand layer deep foundation pit water-stop curtain leakage rapid plugging system according to claim 1, characterized in that: After step five, there is also step six. In step six, a number of steel pipe support piles are driven around the foundation pit, and a layer of waterproof sealing material is sprayed on the inner wall of the steel pipe support pile; the outer wall of the steel pipe support pile is wrapped with a concrete layer reinforced with a steel mesh; a water stop plate is installed on the top of the steel pipe support pile; a complete drainage system is formed by setting up drainage pipes and connecting multiple steel pipe support piles to guide the water flow inside and outside the foundation pit to the external drainage system; the drainage pipe includes a longitudinal drainage pipe and a transverse drainage pipe, the longitudinal drainage pipe is arranged along the depth direction of the foundation pit, and the transverse drainage pipe connects multiple longitudinal drainage pipes.

9. A rapid leakage plugging system for a water-rich silt sand layer deep foundation pit water-stop curtain, constructed by the method described in any one of claims 1 to 8.

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