Jacking prevention and treatment method for uneven deformation of existing underground structure adjacent to slope

Abstract

The invention discloses a jacking prevention and treatment method for uneven deformation of an existing adjacent-slope underground structure. The jacking prevention and treatment method comprises the steps that a reinforcement cage is manufactured, a plurality of cylindrical reinforcing reinforcement cages are integrated in the reinforcement cage, and circular-truncated-cone-shaped sleeves are placed in the cylindrical reinforcing reinforcement cages; the reinforcement cage is hoisted and lowered to the designed elevation, then concrete is poured, an underground diaphragm wall structure is formed and maintained, and a reserved hole is formed in the position of the circular-truncated-cone-shaped sleeve; foundation pit excavation is conducted, and in the foundation pit excavation process and after excavation is completed, if it is monitored that inclination or sedimentation exceeding the limiting value happens to the existing structure, macromolecule waterproof coiled materials are laid on the inner side walls of the reserved holes; a prefabricated pipe curtain with a lifting air bag and an air bag grouting pipe integrated on the upper portion is gradually pressed into the soil body below the existing underground structure through the reserved hole; grouting reinforcement is conducted on the interior of the pipe roofing; grouting is conducted on all layers of bags in sequence from deep to shallow through bag grouting pipes; and after grouting of the bag is completed, the reserved hole is blocked.

Description

Technical Field

[0001] This invention pertains to slope protection, specifically a method for preventing uneven deformation and lifting of existing underground structures on slopes. Background Technology

[0002] When foundation pits or slopes are constructed near underground structures, the construction can cause deformation of the foundation structure, inducing uneven settlement of the existing structure. Existing underground structures are sensitive structures with extremely low tolerance for deformation. Current engineering standards use millimeter-level benchmarks for deformation control indicators such as settlement and horizontal displacement, imposing strict limits on both single and cumulative deformation.

[0003] To address the aforementioned deformation issues, existing technologies often employ active jacking as a deformation compensation method. This technology involves installing a jacking device beneath the existing structure to apply active force to counteract settlement and restore the structure to its initial design elevation. However, this technology suffers from two major drawbacks: First, the installation and operation of the jacking device necessitate the creation of large working openings within the slope support system. These openings often penetrate key load-bearing components such as reinforced concrete retaining piles, severely compromising the integrity of the support structure, significantly weakening its lateral stiffness, and potentially causing water leakage from the pit sidewalls, threatening construction safety. Second, existing active jacking methods lack a dynamic adjustment mechanism based on real-time deformation data. When the jacking force is unbalanced with the structure's self-weight and the surrounding soil constraint forces, localized plastic deformation can easily occur, inducing secondary settlement and making millimeter-level precision control difficult. Furthermore, grouting lifting can also be used to correct the tilt and settlement of existing buildings, but the grout flow direction and setting time are difficult to control precisely, easily leading to uneven lifting and poor correction accuracy. Summary of the Invention

[0004] In order to solve the technical problems existing in the prior art, the purpose of this invention is to provide a lifting and correction scheme that can "uniformly, non-destructively, with high precision and coordinated control" for existing underground structures that have tilted, thereby safely, efficiently and accurately restoring their design alignment and minimizing interference with normal operation.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: The method for preventing uneven deformation and lifting of existing underground structures on slopes includes the following steps: Step 1: Fabricate a steel reinforcement cage and integrate multiple cylindrical reinforcing steel cages inside the steel reinforcement cage. A sleeve is placed inside the cylindrical reinforcing steel cage. Step 2: Hoist the steel cage from Step 1 and lower it to the design elevation, then pour concrete to form a diaphragm wall structure and cure it, creating pre-reserved holes at the sleeve positions; Step 3 involves excavating the foundation pit. If, during or after the excavation, the existing structure is found to tilt or settle beyond the limit, Step 4 is initiated immediately. Step 4: Drill holes at the reserved cavity locations to clear the concrete from the sleeve and both sides of the sleeve. Lay a polymer waterproof membrane on the inner wall of the reserved cavity. Gradually press the precast pipe curtain, which integrates lifting airbags at the top, into the soil beneath the existing underground structure through the reserved cavity, and accurately position it in the section to be lifted according to the settlement curve. After the pipe curtain is in place, insert a hollow cylindrical water-stop sealing plug at the cavity outlet to complete the waterproof sealing. Then, remove the soil from the pipe curtain using soil removal facilities. Step 5: Grout the interior of the pipe curtain for reinforcement; Step 6: Grout each layer of the bag in sequence from deep to shallow through the grouting pipe; after the bag grouting is completed, seal the reserved holes.

[0006] As a further technical solution, the process of fabricating the reinforcing cage in step 1 is as follows: The thickness and length of the diaphragm wall are determined based on the dimensions of the foundation pit. Vertical continuous reinforcement and additional vertical reinforcement are configured and lapped with horizontal reinforcement. A vertical steel column is set at a predetermined interval along the longitudinal direction. Between every two vertical steel columns, four horizontal steel beams are set, including two upper and two lower beams on the inner and outer sides. The upper and lower horizontal steel beams are connected at the mid-span by two connecting steel plates, which divide the beams into three equal sections along the length. A cylindrical reinforcing steel cage is configured in each section. The cylindrical reinforcing steel cage is welded and fixed to the vertical continuous reinforcement, horizontal reinforcement, and horizontal steel beams. A frustum-shaped sleeve is pre-embedded in each cylindrical reinforcing steel cage.

[0007] As a further technical solution, holes are pre-drilled at the connection points between the horizontal steel beams and the vertical steel columns, and a reliable connection is achieved using high-strength connecting bolts.

[0008] As a further technical solution, the connection between the vertical steel column and the reinforcing cage is achieved by symmetrically opening holes in the flange of the steel column, inserting short reinforcing bars, lapping the two ends with the horizontal reinforcing bars of the reinforcing cage, and welding at the insertion points to achieve force transmission.

[0009] As a further technical solution, diagonal reinforcing bars are also provided between the horizontal bars and the vertical continuous bars, and the diagonal reinforcing bars connect the horizontal bars and the vertical continuous bars.

[0010] As a further technical solution, the cylindrical reinforcing steel cage is cone-shaped.

[0011] As a further technical solution, each bag opening on the precast tube curtain has a tightening structure to prevent slurry leakage between two bags.

[0012] As a further technical solution, by controlling the grouting volume of different bags, the lifting height at each location can be adjusted, thereby achieving precise correction of deformation of existing underground structures.

[0013] As a further technical solution, all the lifting airbags on the pipe curtain are simultaneously grouted and pressurized, and the lifting amount at each point is precisely controlled based on the real-time data fed back by the monitoring system, until the existing structure is lifted and stabilized to the design elevation.

[0014] As a further technical solution, before the grouting of the bladder, the grouting pipe of the bladder is connected to the lifting airbag located at the innermost side of the precast pipe curtain.

[0015] Compared with existing technologies, the tilting and lifting technology of this invention has the following advantages: This invention possesses a high degree of foresight and integration, achieving "active protection." It proactively integrates future tilt correction requirements into the diaphragm wall design stage of the foundation pit support. By pre-installing steel frames, cylindrical reinforcing steel cages, and frustum-shaped sleeves within the reinforcing cage, pre-reserved holes are formed during the pouring of the diaphragm wall, creating permanent tilt correction channels. This endows the project with "active protection" capabilities; once tilting of the existing underground structure is detected later, efficient tilt correction can be initiated immediately, avoiding the passive, hasty, and costly nature of traditional "post-event remediation" methods, and achieving a fundamental shift from passive emergency response to proactive control.

[0016] This invention solves the feasibility problem of construction in confined spaces. In narrow spaces adjacent to existing underground structures, traditional large-scale lifting equipment is difficult to access. This invention cleverly avoids space constraints by pre-drilling holes and using an "inside-out" construction method to precisely embed the pipe jacking and airbag system beneath the existing underground structure. This method eliminates the need for large-scale excavation directly above or to the side of the existing underground structure, minimizing disturbance to the surrounding environment and the existing structure.

[0017] This invention provides a uniform and controllable lifting process without damaging existing underground structures. Using airbags as the lifting actuators, it provides a gentle and uniform surface load, effectively avoiding stress concentration and the risk of localized pressure damage to existing underground structure segments caused by traditional point-loading methods such as jacks. Combined with a high-precision monitoring system, it achieves millimeter-level precision control, ensuring that the existing underground structure smoothly and linearly restores its designed configuration during lifting, eliminating secondary damage.

[0018] This invention establishes a reliable three-dimensional waterproofing and sealing system. To address the risk of water leakage caused by reserved holes in diaphragm walls, this invention designs multiple progressive sealing defenses: the opening of the reserved hole is sealed with a polymer roll material, a funnel-shaped water-swellable sealing component, and a rubber-based sealing plug. This composite sealing system can effectively withstand water and soil pressure, ensuring the sealing reliability of the reserved channel interface after the foundation pit is excavated and throughout the entire tilting process, thus guaranteeing construction safety.

[0019] This invention features a robust and durable structure with a highly reliable pre-installed system. Vertical steel columns and horizontal steel beams are integrated within the diaphragm wall reinforcement cage, forming a sturdy internal framework that significantly enhances the overall rigidity and stability of the cage. Simultaneously, cylindrical reinforcing cages are used for the pre-installed openings, ensuring the structural strength of the opening area during concrete pouring and long-term use, preventing damage due to stress concentration, and guaranteeing the long-term effective service performance of the pre-installed system. Attached Figure Description

[0020] To more clearly illustrate the details of this invention, the accompanying drawings used in the description will be briefly introduced below. The drawings described below are merely some structural drawings of this invention and should not be regarded as limiting the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0021] Figure 1 This is a horizontal cross-sectional view of the diaphragm wall reinforcement cage. Figure 2 This is a front view of the diaphragm wall reinforcement cage; Figure 3 Detailed drawing of the cylindrical steel reinforcement cage; Figure 4 Sectional view of the diaphragm wall reinforcement cage (1-1); Figure 5 This is a longitudinal section view of the opening in the diaphragm wall. Figure 6 Detailed drawing of the connection between the steel section and the steel beam; Figure 7 Detailed drawing of the connection between the steel section and the reinforcing cage; Figures 8(a) and 8(b) show the tubular sac without being raised; Figure 9 Diagram showing the lifting of the tube curtain bag; Figure 10 This is a cross-sectional view before the lifting. Figure 11 This is a cross-sectional view after the elevation. Among them: 1-Horizontal reinforcement, 2-Vertical continuous reinforcement, 3-Vertical additional reinforcement, 4-Vertical steel column, 5-Horizontal steel beam, 6-Frustum sleeve, 7-Circular reinforcing steel bar, 8-Cylindrical reinforcing steel cage, 9-Diaphragm wall, 10-High-strength connecting bolt, 11-Hollow cylindrical water-stop sealing plug, 12-Precast pipe curtain, 13-Short steel bar, 14-Vertical reinforcing steel plate of steel beam, 15-Diagonal reinforcing steel bar, 16-Bag, 17-Bag grouting pipe, 18-Pipe curtain grouting port, 19-Waterproof membrane, 20-Existing underground structure, 21-Waterproof membrane, 22-Soil layer. Detailed Implementation

[0022] It should be noted that the following detailed description is illustrative and intended to provide further explanation of the invention. Unless otherwise specified, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0023] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, unless otherwise expressly indicated by the invention, the singular form is also intended to include the plural form. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof. As described in the background section, existing grouting lifting techniques primarily involve injecting grout into the soil at the bottom of existing underground structures, utilizing the volumetric expansion force of the grout to lift the structures. However, the fluidity and setting time of the grout are difficult to control precisely, easily leading to uneven distribution of lifting force and causing secondary uneven deformation of the existing underground structures, resulting in poor accuracy in controlling the lifting elevation. High-pressure grouting methods lift settled structures using grouting pressure, but they present significant challenges in accurately controlling the amount of settlement recovery and are prone to secondary settlement problems later on. Therefore, this embodiment discloses a novel lifting structure and construction method that features uniform lifting force distribution, high controllability, no damage to existing underground structures, and the ability to achieve multi-point collaborative operation, thereby safely, efficiently, and accurately correcting the tilting problem of existing underground structures.

[0024] The method for preventing uneven deformation and lifting of existing underground structures on slopes proposed in this implementation mainly includes the following steps: Step 1: Fabricate a steel cage and integrate multiple cylindrical reinforcing steel cages inside the steel cage. Place a frustum-shaped sleeve inside the cylindrical reinforcing steel cage. Step 2: Hoist the steel cage from Step 1 and lower it to the design elevation, then pour concrete to form a continuous underground wall structure and cure it, creating a pre-reserved hole at the position of the frustum-shaped sleeve. Step 3 involves excavating the foundation pit. If, during or after the excavation, the existing structure is found to tilt or settle beyond the limit, Step 4 is initiated immediately. Step 4: Lay a polymer waterproof membrane on the inner wall of the reserved hole; gradually press the prefabricated pipe curtain with the lifting airbag integrated on the upper part into the soil below the existing underground structure through the reserved hole, and accurately locate it in the section to be lifted according to the settlement curve; after the pipe curtain is jacked into place, fill the hole outlet with a hollow cylindrical water-stop sealing plug to complete the waterproof sealing; then remove the soil in the pipe curtain through the soil removal facility; Step 5: Grout the interior of the pipe curtain for reinforcement; Step 6: Grout each layer of the bag in sequence from deep to shallow through the grouting pipe; after the bag grouting is completed, seal the reserved holes.

[0025] The following is a detailed explanation of each step: Step 1: Fabricate the steel reinforcement cage and integrate the pre-embedded components inside it.

[0026] Specifically, such as Figure 1 , Figure 2 As shown, the thickness and length of the diaphragm wall are determined according to the dimensions of the foundation pit. Vertical continuous reinforcement bars 2 and additional vertical reinforcement bars 3 are configured and lapped with horizontal reinforcement bars 1. Based on the conventional steel cage framework, a vertical steel column 4 is installed every 3.5 meters longitudinally. Between every two vertical steel columns 4, four horizontal steel beams 5 are installed, including two on each of the inner and outer sides, to enhance the overall structural integrity. To strengthen the rigidity of the horizontal steel beams 5, two connecting steel plates 14 are used to connect the upper and lower opposing horizontal steel beams 5 at their mid-span positions. The two connecting steel plates 14 divide the horizontal steel beams 5 into three equal sections along their length. A cylindrical reinforcing steel cage 8 is installed within each section of the horizontal steel beam 5. The cylindrical reinforcing steel cage 8 is welded and fixed to the vertical continuous reinforcement bars 2, horizontal reinforcement bars 1, and horizontal steel beams 5 to ensure accurate positioning. This is equivalent to evenly placing three cylindrical reinforcing steel cages 8 horizontally within a predetermined area between every two vertical steel columns 4. These three cylindrical reinforcing steel cages 8 form pre-reserved holes after subsequent pouring; each hole is surrounded by a cylindrical reinforcing steel cage 8. Furthermore, such as Figure 4 , Figure 6 As shown, in this embodiment, the connection points between each horizontal steel beam 5 and the vertical steel column 4 are pre-drilled and reliably connected by high-strength connecting bolts 10.

[0027] Furthermore, such as Figure 7As shown, the vertical steel column 4 is connected to the reinforcing cage by symmetrically opening holes in the flange of the steel column, inserting short reinforcing bars 13, and lapping them with the horizontal reinforcing bars 1 of the reinforcing cage at both ends, and welding is performed at the reinforcing bar insertion points to achieve force transmission. To facilitate subsequent drilling operations, a frustum-shaped sleeve 6 is pre-embedded in each cylindrical reinforcing cage as a guide and protective structure for later drilling.

[0028] Furthermore, a diagonal reinforcing bar 15 is provided between the horizontal reinforcing bar 1 and the vertical continuous reinforcing bar 2, and the diagonal reinforcing bar 15 connects the horizontal reinforcing bar 1 and the vertical continuous reinforcing bar 2.

[0029] Furthermore, the aforementioned cylindrical reinforcing cage 8 is a conical reinforcing cage, such as... Figure 3 As shown, during installation, the larger diameter opening is located on the outside of the diaphragm wall, and the smaller diameter opening is located on the inside of the diaphragm wall. For specific installation instructions, please refer to [link / reference needed]. Figure 5 ; In step 2 above, after the steel cage is fabricated, the trenching operation for the diaphragm wall 9 is carried out. The steel cage, which integrates the three-dimensional stiffening frame and the reserved holes, is hoisted and lowered to the design elevation, and then concrete is poured to form the diaphragm wall structure, followed by necessary curing.

[0030] During the concrete pouring process, when the pouring surface rises to the height of the reserved hole, the area should be fully and evenly vibrated to ensure that the concrete densely fills the gaps around the hole and between the stiffening components, thus avoiding quality defects such as honeycomb or voids.

[0031] In step 3 above, the deformation of adjacent existing underground structures is continuously monitored during and after the excavation of the foundation pit. If the monitoring data shows that the deformation does not exceed the allowable value, no corrective measures are initiated; if the existing structure is found to have tilted or settled beyond the limit, subsequent corrective lifting construction is immediately initiated.

[0032] In step 4 above, drilling is first performed at the reserved cavity location to clear the concrete on the inner and outer sides of the frustum-shaped sleeve. (Since the height of the frustum-shaped sleeve is not equal to the thickness of the diaphragm wall, and the frustum-shaped sleeve is also a fully enclosed structure with a hollow interior and top and bottom cover plates, concrete cannot be poured in. However, the inner and outer sides of the frustum-shaped sleeve have grouting capabilities, so it is necessary to clear the concrete on the top and bottom plates and the inner and outer sides of the frustum-shaped sleeve.) Then, the sealing material at the reserved hole is removed, and a polymer waterproof membrane 19 is laid on the inner wall of the hole. Next, the prefabricated pipe curtain 12, which integrates the lifting airbag 16 at the top, is gradually pressed into the soil below the existing underground structure through the reserved hole, and its location is accurately determined in the section to be lifted according to the settlement curve. After the pipe curtain is jacked into place, a hollow cylindrical water-stop sealing plug 11 is inserted at the hole outlet to complete the waterproof sealing; then, the soil in the pipe is removed using a spiral soil removal device. The structural diagrams of the prefabricated tube curtain 12 integrating the lifting airbag 16 are shown in Figure 8(a) and Figure 8(b). Figure 9 , Figure 10 As shown, four sets of grouting bags 16 are arranged along the depth direction on the upper part of the precast pipe curtain 12; grouting pipes 17 are arranged on the pipe wall of the precast pipe curtain 12; before grouting, the grouting pipes 17 are connected to the innermost grouting bag 16; the pipe opening of the precast pipe curtain 12 is the pipe curtain grouting port 18. In step 5 above, grouting reinforcement is carried out on the pipe curtain. Cement-based grout is injected into the internal cavity of the pipe curtain at a uniform speed and evenly through the preset grouting holes. After the grouting is completed, necessary curing is carried out. After the grout strength reaches the design value and meets the load-bearing requirements, the subsequent jacking operation is carried out.

[0033] In step 6 above, four sets of grouting bags 16 are installed along the depth direction on the upper part of the precast pipe curtain 12 for differentiated lifting operations based on the actual tilt and settlement morphology of the existing underground structure. During the lifting operation, grouting is performed on each layer of grouting bags 16 sequentially from deep to shallow through the grouting pipes. Each grouting bag 16 has a tightening structure (such as an elastic rope that can tighten automatically) at its opening. After the grouting pipe 17 is pulled out, it can automatically tighten, preventing grout leakage between two grouting bags 16. By controlling the grouting volume of different grouting bags 16, the lifting height at each location can be adjusted, thereby achieving precise correction of deformation of the existing underground structure. After grouting of each grouting bag 16 is completed, the insertion port of the grouting pipe 17 is immediately sealed with adhesive material to prevent grout backflow or seepage.

[0034] Throughout the lifting process, the aforementioned lifting pipe curtain was repeatedly installed in the entire inclined and subsided section of the existing underground structure. A high-precision monitoring system was deployed inside the existing underground structure, and the lifting airbags within all pipe curtains were activated for synchronous grouting and pressurization. Simultaneously, based on real-time data feedback from the monitoring system, the lifting amount at each point was precisely controlled until the existing structure was lifted and stabilized at the design elevation. After the lifting was completed, high-strength micro-expansion grouting material, i.e., existing rubber-based sealing plugs, was used to permanently seal the reserved holes.

[0035] The aforementioned construction method achieves "active protection." This invention proactively integrates future tilt correction needs into the diaphragm wall design stage of the foundation pit support. By pre-installing steel frames, cylindrical reinforcing steel cages, and frustum-shaped sleeves within the reinforcing cage, pre-reserved holes are formed during the pouring of the diaphragm wall, creating permanent tilt correction channels. This endows the project with "active protection" capabilities. Once tilting of the existing underground structure is detected later, efficient tilt correction can be initiated immediately, avoiding the passive, hasty, and costly nature of traditional "post-event remediation" methods. This represents a fundamental shift from passive emergency response to proactive control.

[0036] The aforementioned construction method solves the feasibility problem of construction in confined spaces. In narrow spaces adjacent to existing underground structures, traditional large-scale lifting equipment is difficult to access. This invention, through pre-installed holes and an "inside-out" construction approach, precisely embeds the pipe jacking and airbag system beneath the existing underground structure, cleverly circumventing space limitations. This method eliminates the need for large-scale excavation directly above or to the side of the existing underground structure, minimizing disturbance to the surrounding environment and the existing structure.

[0037] The above-mentioned construction method ensures a uniform and controllable lifting process without damaging the existing underground structure. Using airbags as the lifting actuator provides a gentle and uniform surface load, effectively avoiding stress concentration and the risk of localized pressure damage to existing underground structure segments caused by traditional point-loading methods such as jacks. Combined with a high-precision monitoring system, millimeter-level precision control can be achieved, ensuring that the existing underground structure smoothly and linearly restores its designed configuration during the lifting process, eliminating secondary damage.

[0038] The above construction method establishes a reliable three-dimensional waterproofing and sealing system. In response to the risk of water leakage caused by the reserved holes in the diaphragm wall, this invention designs a multi-layered sealing defense: a polymer roll material, a funnel-shaped water-swellable sealing component, and a rubber-based sealing plug are installed at the grouting port. This composite sealing system can effectively withstand water and soil pressure, ensuring the sealing reliability of the reserved channel interface after the foundation pit is excavated and during the entire tilting process, thus ensuring construction safety.

[0039] The aforementioned construction method results in a robust and durable structure with a highly reliable pre-installed system. The integrated steel columns and beams within the diaphragm wall reinforcement cage form a sturdy internal framework, significantly enhancing the overall rigidity and stability of the cage. Furthermore, the installation of ring-shaped reinforcing bars in the pre-installed openings ensures the structural strength of the opening area during concrete pouring and long-term use, preventing damage due to stress concentration and guaranteeing the long-term effective service performance of the pre-installed system.

[0040] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preventing uneven deformation and lifting of existing underground structures on slopes, characterized in that, Includes the following steps: Step 1: Fabricate a steel reinforcement cage and integrate multiple cylindrical reinforcing steel cages inside the steel reinforcement cage. Place a frustum-shaped sleeve inside the cylindrical reinforcing steel cage. Step 2: Hoist the steel cage from Step 1 and lower it to the design elevation, then pour concrete to form a continuous underground wall structure and cure it, creating a pre-reserved hole at the position of the frustum-shaped sleeve. Step 3: Excavate the foundation pit. If, during or after the excavation, the existing structure is found to tilt or settle beyond the limit, Step 4 shall be initiated immediately. Step 4: Drill holes at the reserved cavity locations to clear the concrete from the sleeve and both sides of the sleeve. Lay a polymer waterproof membrane on the inner wall of the reserved cavity. The precast pipe curtain, which integrates lifting airbags and grouting pipes at the top, is gradually pressed into the soil beneath the existing underground structure through the reserved cavity, and its location is accurately determined in the section to be lifted based on the settlement curve. After the pipe curtain is in place, a hollow cylindrical water-stop sealing plug is inserted at the cavity outlet to complete the waterproof sealing. Then, the soil in the pipe curtain is removed using soil removal facilities. Step 5: Grout the interior of the pipe curtain for reinforcement; Step 6: Grout each layer of the bag in sequence from deep to shallow through the grouting pipe; after the bag grouting is completed, seal the reserved holes.

2. The method for preventing uneven deformation and lifting of existing underground structures on slopes as described in claim 1, characterized in that, The process of fabricating the steel cage in step 1 is as follows: The thickness and length of the diaphragm wall are determined based on the dimensions of the foundation pit. Vertical continuous reinforcement and additional vertical reinforcement are configured and lapped with horizontal reinforcement. A vertical steel column is set at a predetermined interval along the longitudinal direction. Between every two vertical steel columns, four horizontal steel beams are set, including two upper and two lower beams on the inner and outer sides. The upper and lower horizontal steel beams are connected at the mid-span by two connecting steel plates, which divide the beams into three equal sections along the length. A cylindrical reinforcing steel cage is configured in each section. The cylindrical reinforcing steel cage is welded and fixed to the vertical continuous reinforcement, horizontal reinforcement, and horizontal steel beams. A frustum-shaped sleeve is pre-embedded in each cylindrical reinforcing steel cage.

3. The method for preventing uneven deformation and lifting of existing underground structures on slopes as described in claim 2, characterized in that, Holes are pre-drilled at the connection points between each horizontal steel beam and the vertical steel column, and a reliable connection is achieved using high-strength connecting bolts.

4. The method for preventing uneven deformation and lifting of existing underground structures on slopes as described in claim 2, characterized in that, The connection between the vertical steel column and the reinforcing cage is achieved by symmetrically opening holes in the flange of the steel column, inserting short reinforcing bars, lapping the two ends with the horizontal reinforcing bars of the reinforcing cage, and welding at the reinforcing bar insertion points to achieve force transmission.

5. The method for preventing uneven deformation and lifting of existing underground structures on slopes as described in claim 2, characterized in that, Diagonal reinforcing bars are also provided between the horizontal bars and the vertical continuous bars, and the diagonal reinforcing bars connect the horizontal bars and the vertical continuous bars.

6. The method for preventing uneven deformation and lifting of existing underground structures on slopes as described in claim 2, characterized in that, The cylindrical reinforcing steel cage is cone-shaped.

7. The method for preventing uneven deformation and lifting of existing underground structures on slopes as described in claim 1, characterized in that, Each of the precast tube curtains has a tightening structure at its opening to prevent slurry leakage between two tubes.

8. The method for preventing uneven deformation and lifting of existing underground structures on slopes as described in claim 1, characterized in that, By controlling the grouting volume of different bladders, the lifting height at each location can be adjusted, thereby achieving precise correction of deformation of existing underground structures.

9. The method for preventing uneven deformation and lifting of existing underground structures on slopes as described in claim 1, characterized in that, All the lifting airbags on the pipe curtain are simultaneously grouted and pressurized, and the lifting amount at each point is precisely controlled based on the real-time data fed back by the monitoring system, until the existing structure is lifted and stabilized to the design elevation.

10. The method for preventing uneven deformation and lifting of existing underground structures on slopes as described in claim 1, characterized in that, Before the grouting of the bladder, the grouting pipe of the bladder is connected to the lifting airbag located at the innermost side of the precast pipe curtain.

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