Large-size rectangular broken anti-slide pile reinforcing structure for operating railway line

Abstract

The present application relates to anti-slide pile reinforcing technical field, specifically relates to a kind of large-size rectangular broken anti-slide pile reinforcing structure of operating railway line.A kind of "concave" anti-slide pile repair structure of broken pile, including prefabricated steel guard wall, formwork support, embedded part, shear I-beam, steel reinforcement framework, the present application provides a kind of large-size rectangular broken anti-slide pile reinforcing structure with simple structure, convenient construction, good effect, after the stability discrimination safety of potential sliding surface, excavate a "concave" section pile hole in defect pile body and make steel guard wall, "concave" pile inlay shear I-beam and once cast concrete forming, form the inner package of defect pile body, under the premise of guaranteeing normal operation of railway line, realize defect pile reinforcing, prevent pile body defect continue to deteriorate, eliminate landslide instability hidden danger.

Description

Technical Field

[0001] This invention relates to the field of anti-slide pile reinforcement technology, specifically to a reinforcement structure for large-size rectangular damaged anti-slide piles on an operating railway line. Background Technology

[0002] Anti-slide piles are piles that penetrate the landslide body and are embedded in the sliding bed. They are used to resist the sliding force of the landslide body and stabilize the slope. They are suitable for the protection of shallow and medium-thick landslides. With their strong anti-slide ability, economic rationality and convenient construction, they have become one of the main measures for the protection of railway cutting slopes.

[0003] However, due to defects in early construction such as poor concrete pouring quality, water leakage in the retaining wall, and poor hole formation, coupled with the long-term effects of environmental chemical corrosion, root wedging, and freeze-thaw cycles, anti-slide piles inevitably develop cracks, erosion, and water seepage, reducing the shear strength of the pile body. In special circumstances, instability and failure may occur, leading to landslides, which pose a great challenge to the operational safety of railway lines.

[0004] Construction on operating railway lines imposes strict protection requirements on construction procedures such as material transportation and storage, formwork support, and steel cage hoisting. Construction windows are limited, and when using anchor cables, steel pipe piles, or rectangular piles for reinforcement, the construction procedures are cumbersome, the time occupied by the line is long, and the reinforcement effect of the original defective piles is limited, which can easily create secondary hidden danger points and still pose a threat to the operational safety of the railway line. Summary of the Invention

[0005] To address the aforementioned problems, this invention aims to provide a large-size rectangular anti-slide pile reinforcement structure for operating railway lines. After assessing the safety of the potential sliding surface stability, a concave section pile hole is excavated behind the defective pile and a steel retaining wall is constructed. The concave pile is embedded with shear-resistant I-beams and then cast with concrete in one go, forming an inner enclosure for the defective pile. Under the premise of ensuring the normal operation of the railway line, the defective pile is reinforced, preventing further deterioration of the pile defect and eliminating the potential for landslide instability.

[0006] To achieve the above objectives, the main idea of ​​the technical solution adopted by the present invention is as follows: a "concave" shaped anti-slide pile repair structure for wrapping a damaged pile, a precast steel retaining wall, a formwork support, embedded parts, shear-resistant I-beams, and a steel reinforcement cage are included. A "concave" shaped cross-section pile hole is excavated behind the defective pile and a steel retaining wall is constructed. The shear-resistant I-beams are embedded in the "concave" shaped pile. The formwork support is connected to the inner wall of the precast steel retaining wall. Sonic logging tubes are arranged at each corner point in the steel reinforcement cage. A displacement observation point is arranged at the center of the top of the damaged pile.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] A reinforcement structure for large-size rectangular damaged anti-slide piles on an operating railway line is characterized by: including a "concave" shaped anti-slide pile repair structure for wrapping the damaged pile; the "concave" shaped anti-slide pile repair structure is provided with a precast steel protective wall inside, the inner wall of the precast steel protective wall is connected to a template support, the template support is connected to embedded parts, and the "concave" shaped anti-slide pile repair structure is also connected with shear-resistant I-beams and a steel reinforcement skeleton;

[0009] The precast steel retaining wall includes type A and type B components, wherein type A is straight and type B is L-shaped.

[0010] Furthermore, the type A and type B components are fixed in a BBABB sequence to form a concave precast steel retaining wall.

[0011] Furthermore, the template support includes a back rib, a horizontal brace, a triangular reinforcement member, and a diagonal brace; the back rib is connected to the inner wall of the precast steel retaining wall, the horizontal brace is connected to the back rib and the embedded part, the triangular reinforcement member is connected to the back rib and the broken pile, and the diagonal brace is set at the four corners of the precast steel retaining wall.

[0012] Furthermore, the triangular reinforcement includes a support component and a connector for supporting the corner of the damaged pile, wherein the support component and the connector are fixedly connected.

[0013] Furthermore, the support component includes a sector-shaped steel block, on which double-section I-beams are symmetrically arranged on the left and right sides.

[0014] Furthermore, the embedded part includes an embedded steel plate and a φ25 embedded steel bar, which are connected together.

[0015] Furthermore, the steel reinforcement cage includes main bars, stirrups, and reinforcing bars. The main bars and stirrups are evenly distributed in the "U"-shaped anti-slide pile repair structure, and the reinforcing bars are inserted into the damaged pile at equal intervals in the horizontal and vertical directions.

[0016] Furthermore, the above plan is carried out according to the following steps:

[0017] Step 1: Before excavating the foundation pit, set up protective measures in the excavation area. The baffle is connected and fixed to the existing anchor piles. Temporary protective measures are used to prevent the falling of excavated soil and machinery. Temporary enclosure structures are set up to ensure effective isolation between the construction and operation lines.

[0018] Step 2: Excavate a concave trench with a depth of 1m, and put the precast steel retaining wall A-type and B-type components into the concave trench for assembly and welding. Weld the I-beam back ribs, cross braces, triangular reinforcements and diagonal braces to the pile back embedded parts and the precast steel retaining wall.

[0019] Step 3: After the formwork support construction is completed, the next cycle of excavation and support will be carried out until the design elevation is reached. The surface of the steel plate near the rock mass will be coated with anti-rust paint, and the gap between the precast steel retaining wall and the mountain will be filled with cement grout.

[0020] Step 4: Excavate the foundation pit to the design elevation, drill a 2m deep H-beam trench using a geological drill, insert the lowest section of the shear-resistant H-beam and fix it in place;

[0021] Step 5: Lower and weld the extended shear-resistant I-beams while constructing the steel reinforcement cage. The steel reinforcement cage is connected to the defective pile by embedded steel bars. After the steel reinforcement cage is tied, sonic logging tubes and observation points are arranged at each designed location.

[0022] Step Six: Concrete is poured using a guide pipe, and the integrity of the "U"-shaped pile repair structure is tested after curing.

[0023] The beneficial effects of this invention are as follows: Compared with the prior art, the improvements of this invention are:

[0024] 1. Using precast steel formwork as retaining walls greatly improves the safety and convenience of pile hole excavation; at the same time, large-size shear-resistant I-beams replace the shear and bending reinforcement bars inside the "U"-shaped reinforced piles, reducing the construction safety hazards of hoisting steel cages along operating railway lines.

[0025] 2. Compared with conventional methods such as adding piles and anchor cables to reinforce slopes, the overall solution of wrapping the damaged piles with "concave" piles greatly reduces the complexity of construction on operating railway lines, improves construction efficiency, and avoids the risk of slope slippage caused by local damage to the damaged piles later.

[0026] 3. The "concave" shaped anti-slide pile repair structure is essentially used to repair the original defective piles to enhance the bearing capacity of the pile body, thereby improving the safety of the slope. Attached Figure Description

[0027] Figure 1 This invention provides a concave anti-slide pile repair structure.

[0028] Figure 2 This is a diagram showing the layout of the formwork support and shear-resistant I-beams for the "U"-shaped anti-slide pile repair structure.

[0029] Figure 3 This is a schematic diagram of the steel reinforcement skeleton arrangement of the "concave" shaped anti-slide pile repair structure.

[0030] Figure 4 This is a schematic diagram of a prefabricated type A component.

[0031] Figure 5 This is a schematic diagram of a prefabricated type B component.

[0032] Figure 6This is a schematic diagram of the steel mesh arrangement for repairing the surface of a damaged pile.

[0033] Figure 7 This is a schematic diagram of the welding of shear-resistant I-beams.

[0034] Figure 8 This is a schematic diagram of a grid-like support structure.

[0035] Figure 9 This is a schematic diagram of the layout of monitoring and detection points.

[0036] Figure 10 This is a front view of the triangular reinforcement component.

[0037] Figure 11 This is a schematic diagram of the structure of the triangular reinforced member after it has been subjected to force.

[0038] Figure 12 This is a top-view cross-sectional diagram of the support component.

[0039] Among them: 1. Damaged piles; 2. "U"-shaped anti-slide pile repair structure; 3. Precast steel guardrails; 4. Formwork supports; 5. Embedded parts; 6. Shear-resistant I-beams; 10. Guardrail steel plates; 11. Channel steel; 12. Angle steel; 13. Back ribs; 14. Horizontal braces; 141. Triangular reinforcements; 142. Baffles; 143. Fan-shaped steel blocks; 144. Slide grooves; 145. Sliding blocks; 146. "V"-shaped steel components; 147. Connecting... 15. Connecting parts, 16. Diagonal brace, 17. Embedded steel plate, 18. φ25 embedded steel bar, 19. Welding steel plate, 20. Main reinforcement, 21. Stirrup, 22. Reinforcing bar, 23. Rebar adhesive, 24. Φ8 steel mesh, 25. Surface-embedded steel bar, 26. Roughening of the surface of the damaged pile near the rock, 27. Roughening of the surface of the pile body on the side of the temporary line, 28. "Well" shaped support, 29. Welding hole, 30. Sonic logging tube, 31. Displacement observation point. Detailed Implementation

[0040] To enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0041] A reinforcement structure for large-size rectangular damaged anti-slide piles on an operating railway line includes a concave anti-slide pile repair structure 2 enclosing the damaged pile 1, a precast steel retaining wall 3, formwork support 4, embedded parts 5, shear-resistant I-beams 6, and a steel reinforcement cage. (Please refer to...) Figures 1-12The precast steel retaining wall comes in two types: Type A, which is straight, and Type B, which is L-shaped. Both are constructed by single-sided welding of retaining wall steel plates 10, channel steel 11, and angle steel 12. Both Type A and Type B precast components are 1m high. Due to safety regulations for operating railway construction and site limitations, large hoisting equipment cannot directly enter the construction site during on-site assembly. To reduce the risk of interference to the operating line caused by lowering long steel components, the steel retaining wall is divided into two types of precast components. Manual hoists or other hoisting equipment are used for installation in the pit to reduce labor costs and project risks. To achieve a concave opening arrangement, a fixed BBABB sequence is adopted. After welding the concave precast steel retaining wall in the BBABB sequence, it is placed in the excavated pit. As the pile holes are excavated, the precast steel retaining walls 3 are sequentially lowered and welded together.

[0042] The precast steel retaining wall 3 also serves as a formwork for concrete pouring. This formwork support method fully utilizes the residual resistance of the existing piles to improve the support effect of the steel retaining wall, while making the connection between the components more robust, greatly enhancing the overall structural stability and construction safety. Its formwork support 4 includes back ribs 13, horizontal braces 14, triangular reinforcements 141, and diagonal braces 15, all of which are I-beam components of the same specification. The back ribs 13 are I-beams, circumferentially welded to the inner wall steel plate 10 of the precast steel retaining wall 3, with a distance of 0.5m from the top surface and a vertical spacing of 1m between the back ribs 13. The horizontal braces 14 are double-splitting I-beams, with the back ribs 13 and embedded parts 5 welded to both ends of the horizontal braces 14 respectively. The spacing between the two horizontal braces is determined according to the cross-sectional dimensions of the rectangular anti-slide pile, with a vertical spacing of 1m. The diagonal brace 15 is a double-section I-beam. The diagonal brace 15 is set at the four corners of the precast steel retaining wall 3, and its two ends are welded to the inner wall steel plate 10 of the B-type precast component. The angle between its axis and the inner wall steel plate 10 of the steel retaining wall is 45°.

[0043] Embedded part 5 consists of a 10mm embedded steel plate 16 and a φ25 embedded steel bar 17 welded together by through-hole welding. The φ25 steel bar 17 is embedded 500mm into the damaged pile body. The positions of the embedded parts correspond to the positions of the cross braces.

[0044] The shear-resistant I-beams 6 are arranged behind the defective pile, with their bottoms extending 2m into the stable rock surface. The number and lateral spacing of these I-beams should be determined by actual calculation, but should not be less than 4. Each section of the shear-resistant I-beams 6 is 1m long. Welding inside the pile hole uses 18 pairs of 2cm steel plates for back welding on both sides of the web and flanges. The weld length should not be less than 5 ( Furthermore, it should meet the relevant requirements in the "Standard for Design of Steel Structures" (GB50017-2017).

[0045] The steel reinforcement cage includes main bars 19, stirrups 20, and reinforcing bars 21 for the damaged pile. The main bars 19 are bundled in groups of three. The stirrups 20 are spaced 20cm vertically. After roughening the surface 25 near the rock face of the damaged pile, reinforcing bars 21 are inserted at 40cm horizontal and vertical intervals. The exposed portions are connected to the "U"-shaped pile reinforcing bars with 135° hooks. Sonic logging tubes 29 are placed at each corner of the steel reinforcement cage, and a displacement observation point 30 is placed at the center of the top of the damaged pile 1. Concrete is poured into the steel reinforcement cage and cured to form the "U"-shaped anti-slide pile repair structure 2.

[0046] The surface treatment of damaged pile 1 involves roughening the surface of the pile body on the adjacent line side by 26, then installing rebar, hanging Φ8 steel mesh 23, and erecting formwork to pour the surface concrete. A "well"-shaped bracket 27 is installed on the Φ8 steel mesh 23, which is welded to the surface-embedded rebar 24 to fix the Φ8 steel mesh 23. The "well"-shaped bracket 27 is made of four rebars welded together, with a welding hole 28 in the middle that matches the diameter of the implanted rebar 24.

[0047] Example

[0048] When reinforcing damaged anti-slide piles on operating railway lines, a concave anti-slide pile repair structure 2 is used to encase the damaged pile 1. This concave anti-slide pile repair structure 2 includes a precast steel retaining wall 3, a formwork support 4, embedded parts 5, shear-resistant I-beams 6, and a reinforcing steel skeleton. The precast steel retaining wall 3 comes in two types: Type A is a straight precast component, and Type B is an L-shaped precast component. Both are made by double-sided welding of retaining wall steel plates 10, channel steel 11, and angle steel 12. Both Type A and Type B precast components are 1m high. During on-site assembly, they are welded into a concave precast steel retaining wall using the BBABB sequence, placed in the excavation pit, and lowered sequentially as the pile hole is excavated, and then welded together.

[0049] The precast steel retaining wall 3 also serves as a formwork for concrete pouring. Its formwork support 4 includes back ribs 13, horizontal braces 14, triangular reinforcements 141, and diagonal braces 15, all of which are I-beam components of the same specification. The back ribs 13 are I-beams, circumferentially welded to the inner wall steel plate 10 of the precast steel retaining wall 3, with a distance of 0.5m from the top surface and a vertical spacing of 1m between the back ribs 13. The horizontal braces 14 are double-splitting I-beams, with the back ribs 13 and embedded parts 5 welded to both ends of the horizontal braces 14 respectively. The spacing between the two horizontal braces is determined according to the cross-sectional dimensions of the rectangular anti-slide pile, and the vertical spacing is 1m. Two triangular reinforcement members 141 are installed at a vertical distance of 1m from the horizontal brace 14, located at the two diagonal positions of the damaged pile 1. Each triangular reinforcement member 141 includes a support component supporting the corner of the damaged pile and a connector 147 welded to the bottom of two double-I-beams of the support component. The connector 147 is welded to the back rib 13. The support component is formed by symmetrically arranged double-I-beams on the left and right sides of a fan-shaped steel block. Two grooves 144 are prefabricated on the double-I-beams, and a baffle 142 is provided at one end of the groove 144. The baffle acts as a one-way valve, allowing the slider 145 to enter the groove but not exit it. Then, the slider 145, which is welded to the fan-shaped steel block 143, is inserted into the groove 144. The slider 145 is a combined slider formed by integrally molding a cuboid and a sphere. The end of the groove 144 is triangular, which acts as a limit. After the slider 145 moves to the end of the groove, it can stop the slider.

[0050] It should be noted that the support component is in direct contact with the corners of the damaged pile 1, providing support for the damaged pile 1. Therefore, by connecting the double-section I-beams and the sector-shaped steel block 143 together through sliders and grooves, when the damaged pile 1 is subjected to external force, the slider 145 on the sector-shaped steel block 143 moves along the groove 144 prefabricated inside the double-section I-beams. The final result of this movement is that the two double-section I-beams and the sector-shaped steel block 143 are tightly connected together, making the triangular reinforcement 141 more firmly bonded together, preventing the weld from breaking as would occur with welding. At the same time, since the contact surface between the support component and the damaged pile 1 is arc-shaped, when the damaged pile is subjected to external force, the force is distributed to the two double-section I-beams of the support component, making it more robust than a single double-section I-beam bearing the force directly. The connector 147 is welded to the back rib 13 at both ends, providing a fixing function for the support component.

[0051] According to the design scheme of this application, triangles possess stability, and the triangular reinforcement 141 makes the reinforcement structure of the damaged pile 1 more robust. Furthermore, a "V"-shaped steel component 146, composed of two 10mm steel plates, is welded to the contact surface between the damaged pile 1 and the triangular reinforcement 141. When the triangular reinforcement 141 supports the damaged pile 1, it protects the edges and corners of the damaged pile 1 from breakage or fracture due to stress, preventing the formation of secondary potential hazards and making railway line operation safer.

[0052] The diagonal brace 15 is a double-section I-beam. The diagonal brace 15 is set at the four corners of the precast steel retaining wall 3, and its two ends are welded to the inner wall steel plate 10 of the B-type precast component. The angle between its axis and the inner wall steel plate 10 of the steel retaining wall is 45°.

[0053] Embedded part 5 consists of a 10mm embedded steel plate 16 and a φ25 embedded steel bar 17 welded together by through-hole welding. The φ25 steel bar 17 is embedded 500mm into the damaged pile body. The positions of the embedded parts correspond to the positions of the cross braces.

[0054] The shear-resistant I-beams 6 are arranged behind the defective pile, and the bottom should penetrate 2m into the stable rock surface. The number and lateral spacing should be determined by actual calculation, but should not be less than 4. Each section of the shear-resistant I-beams 6 is 1m long. Welding inside the pile hole uses 18 pairs of 2cm steel plates for back welding on both sides of the web and flanges. The weld length should not be less than 5 ( Furthermore, it should meet the relevant requirements in the "Standard for Design of Steel Structures" (GB50017-2017).

[0055] The reinforcing steel cage includes main bars 19, stirrups 20, and reinforcing bars 21 for the damaged pile. The main bars 19 are bundled in groups of three. The stirrups 20 are spaced 20cm vertically. After roughening the surface of the damaged pile near the rock (25), reinforcing bars 21 are inserted at 40cm intervals horizontally and vertically. The exposed portions are connected to the "U"-shaped pile reinforcing bars with 135° hooks. Surface treatment of the damaged pile 1 involves roughening the surface of the pile body on the adjacent road side (26), then installing reinforcing bars, hanging Φ8 steel mesh 23, and erecting a formwork to pour the surface concrete. A "well"-shaped support 27 is installed on the Φ8 steel mesh 23, welded to the surface-inserted reinforcing bars 24 to fix the Φ8 steel mesh 23. The "well"-shaped support 27 is formed by welding four reinforcing bars together, with a welding hole 28 in the middle matching the diameter of the inserted reinforcing bars 24. Sonic logging tubes 29 are arranged at each corner of the reinforcing steel cage, and a displacement observation point 30 is arranged at the top center of the damaged pile 1. Concrete is poured into the reinforcing steel cage and cured to form the "U"-shaped anti-slide pile repair structure 2.

[0056] This embodiment also provides a reinforcement structure for large-size rectangular damaged anti-slide piles on an operating railway line. The reinforcement is achieved using the anti-slide pile combination reinforcement structure and method of this invention, specifically including the following steps:

[0057] Step 1: Before excavating the foundation pit, set up protective measures in the excavation area. The baffle is connected and fixed to the existing anchor piles. Temporary protective measures are used to prevent the falling of excavated soil and machinery. Temporary enclosure structures are set up to ensure effective isolation between the construction and operation lines.

[0058] Step 2: Excavate a concave trench with a depth of 1m, and put the precast steel retaining wall A-type and B-type parts into the concave trench for assembly and welding. Weld the I-beam back rib 13, cross brace 14, triangular reinforcement and diagonal brace 15 to the pile back embedded part 5 and the precast steel retaining wall 3.

[0059] Step 3: After the formwork support 4 is completed, proceed with the next cycle of excavation and support until the design elevation is reached. Apply anti-rust paint to the surface of the steel plate near the rock mass, and fill the gaps between the precast steel retaining wall and the mountain with cement grout.

[0060] Step 4: Excavate the foundation pit to the design elevation, drill a 2m deep H-beam trench using a geological drill, insert the lowest section of shear-resistant H-beam 6 and fix it in place;

[0061] Step 5: Lower and weld the extended shear-resistant I-beam 6 and simultaneously construct the steel reinforcement cage. The steel reinforcement cage is connected to the defective pile by embedded steel bars. After the steel reinforcement cage is tied, sonic logging tubes 29 and observation points 30 are arranged at each designed location.

[0062] Step Six: Concrete is poured using a guide pipe, and the integrity of the "U"-shaped pile repair structure is tested after curing.

[0063] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A reinforcement structure for large-size rectangular anti-slide piles on an operating railway line, characterized in that: The structure includes a concave anti-slide pile repair structure (2) for wrapping the damaged pile (1); the concave anti-slide pile repair structure (2) is provided with a precast steel retaining wall (3) inside, the inner wall of the precast steel retaining wall (3) is connected to a template support (4), the template support (4) is connected to an embedded part (5), and the concave anti-slide pile repair structure (2) is also connected with a shear-resistant I-beam (6) and a steel reinforcement skeleton. The precast steel retaining wall (3) includes type A and type B components, wherein type A is straight and type B is L-shaped; The template support (4) includes a back rib (13), a horizontal brace (14), a triangular reinforcement (141), and a diagonal brace (15); the back rib (13) is connected to the inner wall of the precast steel retaining wall (3), the horizontal brace (14) is connected to the back rib (13) and the embedded part (5), the triangular reinforcement (141) is connected to the back rib (13) and the damaged pile (1), and the diagonal brace (15) is set at the four corners of the precast steel retaining wall (3).

2. The large-size rectangular anti-slide pile reinforcement structure for operating railway lines according to claim 1, characterized in that: The type A and type B components are fixed in a BBABB sequence to form a "concave" shaped precast steel retaining wall.

3. The large-size rectangular anti-slide pile reinforcement structure for operating railway lines according to claim 1, characterized in that: The triangular reinforcement member (141) includes a support component and a connector (147) for supporting the corner of the damaged pile, and the support component and the connector (147) are fixedly connected.

4. The large-size rectangular anti-slide pile reinforcement structure for operating railway lines according to claim 3, characterized in that: The support component includes a fan-shaped steel block (143), on which double-I-beams are symmetrically arranged on the left and right sides.

5. The large-size rectangular anti-slide pile reinforcement structure for operating railway lines according to claim 4, characterized in that: The embedded part (5) includes an embedded steel plate (16) and a φ25 embedded steel bar (17), which are connected together.

6. The large-size rectangular anti-slide pile reinforcement structure for operating railway lines according to claim 5, characterized in that: The steel reinforcement cage includes main bars (19), stirrups (20) and steel bars (21). The main bars (19) and stirrups (20) are evenly distributed in the "concave" shaped anti-slide pile repair structure (2), and the steel bars (21) are evenly inserted into the damaged pile (1) in the horizontal and vertical directions.

7. A method for reinforcing a large-size rectangular damaged anti-slide pile reinforcement structure for an operating railway line according to any one of claims 1-6, characterized in that, Follow these steps: Step 1: Before excavating the foundation pit, set up protective measures in the excavation area. The baffle is connected and fixed to the existing anchor piles. Temporary protective measures are used to prevent the falling of excavated soil and machinery. Temporary enclosure structures are set up to ensure effective isolation between the construction and operation lines. Step 2: Excavate a concave groove with a depth of 1m, and put the precast steel retaining wall type A and type B parts into the concave groove for assembly and welding. Weld the I-beam back rib (13), cross brace (14), triangular reinforcement (141) and diagonal brace (15) to the pile back embedded part (5) and the precast steel retaining wall (3). Step 3: After the template support (4) is completed, the next cycle of excavation and support will be carried out until the design elevation is reached. The surface of the steel plate near the rock mass will be coated with anti-rust paint, and the gap between the precast steel retaining wall (3) and the mountain will be filled with cement grout. Step 4: Excavate the foundation pit to the design elevation, use a geological drill to drill a 2m deep H-beam trench, insert the lowest section of the shear-resistant H-beam (6) and fix it; Step 5: Lower and weld the extended shear-resistant I-beam (6) and simultaneously construct the steel reinforcement cage. The steel reinforcement cage is connected to the damaged pile by implanted steel bars. After the steel reinforcement cage is tied, sonic logging tubes (29) and observation points (30) are arranged at each designed position. Step Six: Concrete is poured using a guide pipe. After curing, the integrity of the "U"-shaped anti-slide pile repair structure is tested.

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