Open-cut tunnel deformation joint anti-seepage structure and construction method under multidirectional displacement

Abstract

The application belongs to the technical field of tunnel engineering, and particularly relates to a deformation joint anti-seepage structure and construction method of an open-cut tunnel subjected to multi-directional dislocation, comprising: first lining concrete and second lining concrete poured on the inner side wall of the tunnel along the length direction of the tunnel, a deformation joint is left between the first lining concrete and the second lining concrete, and an anti-seepage structure is arranged in the deformation joint; in the application, a fabricated middle-buried steel edge rubber waterstop is arranged in the deformation joint, the dislocation between the internal structures of the fabricated middle-buried steel edge rubber waterstop can adapt to the plane dislocation or normal dislocation of the deformation joint without affecting the waterproof performance, so that the situation that the anti-seepage effect of the anti-seepage structure is weakened or even fails due to the dislocation of the tunnel on both sides of the deformation joint is avoided.

Description

Technical Field

[0001] This invention belongs to the field of tunnel engineering technology, and in particular relates to the seepage prevention structure and construction method of deformation joints in open-cut tunnels that are subjected to multi-directional displacement. Background Technology

[0002] At tunnel entrances, the boundary between open and closed sections, and locations with varying surrounding rock conditions, differences in the properties of the surrounding rock in different strata, uneven settlement, thermal expansion and contraction, or accidental external forces can cause longitudinal deformation differences in the tunnel structure during operation. Expansion joints are necessary to offset these displacement differences and ensure structural safety. The seepage prevention performance of these expansion joints, under conditions of coordinated uneven deformation, directly impacts the reliability of the tunnel project. If they lose their waterproofing function, large amounts of groundwater will flow into the tunnel along the expansion joints. Tunnel leakage not only reduces the durability of the tunnel's concrete structure but also threatens the normal operation of various electromechanical facilities within the tunnel, worsens the driving environment, and may even lead to traffic disruption. Therefore, the seepage prevention performance of expansion joints is a weak link in tunnel waterproofing and a crucial factor in ensuring the safe operation of tunnel projects.

[0003] Existing expansion joint waterproofing / seepage prevention structures cannot guarantee their waterproofing / seepage prevention performance while withstanding the displacement and deformation of the expansion joint. Summary of the Invention

[0004] The purpose of this invention is to provide a seepage-proof structure and construction method for expansion joints in open-cut tunnels that can withstand multi-directional displacement, in order to solve the above-mentioned problems.

[0005] To achieve the above objectives, the present invention provides the following solution:

[0006] An anti-seepage structure for expansion joints in open-cut tunnels subjected to multi-directional displacement includes: a first lining concrete and a second lining concrete poured along the tunnel length direction on the inner sidewall of the tunnel, with an expansion joint between the first lining concrete and the second lining concrete, and an anti-seepage structure provided in the expansion joint.

[0007] The seepage prevention structure includes an external rubber waterstop strip circumferentially arranged on the inner wall of the tunnel. The external rubber waterstop strip is located on the water-facing side of the first lining concrete and the second lining concrete. The first lining concrete and the second lining concrete are both cast together with the external rubber waterstop strip.

[0008] The expansion joint is provided with a prefabricated embedded steel-edged rubber waterstop in the inner circumference. The prefabricated embedded steel-edged rubber waterstop is located on the side of the external rubber waterstop away from the backwater surface. The two ends of the prefabricated embedded steel-edged rubber waterstop are respectively fixed in the first lining concrete and the second lining concrete.

[0009] A water collection box is provided circumferentially inside the expansion joint, and the water collection box is close to the back water surface of the first lining concrete and the second lining concrete.

[0010] A waterstop is circumferentially fixed to the backwater surfaces of the first lining concrete and the second lining concrete, and the waterstop is circumferentially arranged and covers the deformation joint.

[0011] Preferably, the expansion joint is filled with asphalt mastic, which is located between the external rubber waterstop and the water collection box, and a resistance heating metal wire is embedded in the asphalt mastic.

[0012] Preferably, a PE foam rod and a high-density polyurethane sealant are circumferentially disposed between the water receiving box and the asphalt mastic, with the high-density polyurethane sealant close to the water receiving box.

[0013] Preferably, the prefabricated embedded steel-edged rubber waterstop includes two circumferentially arranged rubber strips. One end of each rubber strip is fixedly connected to a steel edge strip. One of the steel edge strips is fixedly connected to the first lining concrete by a first reinforcing bar, and the other end extends into the expansion joint and is fixedly connected to a rubber-coated stainless steel male buckle. The other steel edge strip is fixedly connected to the second lining concrete by a second reinforcing bar, and the other end extends into the expansion joint and is fixedly connected to a rubber-coated stainless steel female buckle. The rubber-coated stainless steel male buckle and the rubber-coated stainless steel female buckle are compatible, and a waterstop plug is provided between the rubber-coated stainless steel male buckle and the rubber-coated stainless steel female buckle.

[0014] Preferably, both the first lining concrete and the second lining concrete have circumferentially embedded steel pads on their back surfaces. Each of the two embedded steel pads has several screws inserted through it. One end of each screw extends into the first lining concrete / second lining concrete, and the other end of each screw passes through the embedded steel pad and the waterstop and is threadedly connected to a nut. The connection between the screw and the nut is coated with a quick-setting rubber asphalt waterproof coating.

[0015] Preferably, a polypropylene waterproof membrane is laid on the tunnel floor, and the side of the polypropylene waterproof membrane away from the tunnel floor is sprayed with a reverse-adhesive quick-setting rubber asphalt waterproof coating; a waterproof mortar is laid on the tunnel sidewall, and the side of the waterproof mortar away from the tunnel sidewall is sprayed with the reverse-adhesive quick-setting rubber asphalt waterproof coating; an SBS waterproof membrane is laid on the tunnel roof, and the side of the SBS waterproof membrane away from the tunnel roof is sprayed with a quick-setting rubber asphalt waterproof coating; the external rubber waterstop is laid on the reverse-adhesive quick-setting rubber asphalt waterproof coating and the quick-setting rubber asphalt waterproof coating at the position corresponding to the deformation joint.

[0016] The construction method for seepage prevention structures of expansion joints in open-cut tunnels subjected to multi-directional displacement includes the following steps:

[0017] Step 1: Determine the location of the expansion joint;

[0018] Step 2: Lay an external rubber waterstop at the expansion joint location;

[0019] Step 3: Erect formwork on both sides of the expansion joint, pour the first lining concrete and the second lining concrete, and embed both ends of the prefabricated embedded steel edge rubber waterstop into the first lining concrete and the second lining concrete respectively.

[0020] Step 4: Install a water collection box inside the expansion joint, and fix a waterstop around the back surface of the first lining concrete and the second lining concrete, with the waterstop covering the expansion joint.

[0021] Step 5: Installation complete.

[0022] Compared with the prior art, the present invention has the following advantages and technical effects:

[0023] In this invention, by setting a prefabricated embedded steel-edged rubber waterstop in the expansion joint, the misalignment between the internal structures of the prefabricated embedded steel-edged rubber waterstop can adapt to the planar or normal misalignment of the expansion joint without affecting the waterproof performance, thereby avoiding the situation where the seepage prevention effect of the seepage prevention structure is weakened or even fails due to the misalignment of the tunnels on both sides of the expansion joint. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the anti-seepage structure of the tunnel bottom wall deformation joint in this invention;

[0026] Figure 2 This is a schematic diagram of the anti-seepage structure of the expansion joint in the tunnel roof of the present invention;

[0027] Figure 3 This is a schematic diagram of the anti-seepage structure of the tunnel sidewall deformation joint in this invention;

[0028] Figure 4 This is a schematic diagram of the prefabricated embedded steel-edged rubber waterstop in this invention.

[0029] The components include: 1. Polypropylene waterproof membrane; 2. Reverse-adhesive quick-setting rubber asphalt waterproof spray coating; 3. External rubber waterstop; 4. Asphalt mastic; 5. Resistance heating metal wire; 6. Prefabricated embedded steel-edged rubber waterstop; 7. PE foam rod; 8. High-density polyurethane sealant; 9. Water collection box; 10. Waterstop; 11. Embedded steel pad; 12. Screw; 13. Nut; 14. Quick-setting rubber asphalt waterproof spray coating; 15. SBS waterproof membrane; 16. Waterproof mortar; 17. Rubber strip; 18. Rubber-wrapped stainless steel male buckle; 19. Rubber-wrapped stainless steel female buckle; 20. Waterstop plug; 21. Steel edge strip; 22. First lining concrete; 23. Second lining concrete; 24. First reinforcing bar; 25. Second reinforcing bar. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] Reference Figures 1 to 4 The present invention discloses a seepage-proof structure for expansion joints in open-cut tunnels that can withstand multi-directional displacement, comprising: a first lining concrete 22 and a second lining concrete 23 poured on the inner wall of the tunnel along the tunnel length direction, with an expansion joint between the first lining concrete 22 and the second lining concrete 23, and a seepage-proof structure provided in the expansion joint.

[0033] The seepage prevention structure includes an external rubber waterstop 3 circumferentially set on the inner wall of the tunnel. The external rubber waterstop 3 is located on the water-facing side of the first lining concrete 22 and the second lining concrete 23. The first lining concrete 22 and the second lining concrete 23 are both cast together with the external rubber waterstop 3.

[0034] An assembled steel-edged rubber waterstop 6 is installed in the inner circumference of the expansion joint. The assembled steel-edged rubber waterstop 6 is located on the side away from the back water surface of the outer rubber waterstop 3. The two ends of the assembled steel-edged rubber waterstop 6 are respectively fixed in the first lining concrete 22 and the second lining concrete 23.

[0035] A water collection box 9 is provided on the inner circumference of the expansion joint, and the water collection box 9 is close to the back water surface of the first lining concrete 22 and the second lining concrete 23.

[0036] A waterstop 10 is circumferentially fixed to the backwater surface of the first lining concrete 22 and the second lining concrete 23. The waterstop 10 is circumferentially arranged and covers the deformation joint.

[0037] The scheme was further optimized by filling the expansion joint with asphalt mastic 4. The asphalt mastic 4 was located between the external rubber waterstop 3 and the water receiving box 9. A resistance heating metal wire 5 was embedded in the asphalt mastic 4.

[0038] The design was further optimized by circumferentially installing PE foam rods 7 and high-density polyurethane sealant 8 between the water collection box 9 and the asphalt mastic 4, with the high-density polyurethane sealant 8 close to the water collection box 9.

[0039] Further optimizing the scheme, the prefabricated embedded steel-edged rubber waterstop 6 includes two circumferentially arranged rubber strips 17. One end of the rubber strip 17 is fixedly connected to a steel edge strip 21. One of the steel edge strips 21 is fixedly connected to the first lining concrete 22 by a first reinforcing bar 24, and the other end extends into the expansion joint and is fixedly connected to a rubber-coated stainless steel male buckle 18. The other steel edge strip 21 is fixedly connected to the second lining concrete 23 by a second reinforcing bar 25, and the other end extends into the expansion joint and is fixedly connected to a rubber-coated stainless steel female buckle 19. The rubber-coated stainless steel male buckle 18 and the rubber-coated stainless steel female buckle 19 are compatible, and a waterstop plug 20 is provided between the rubber-coated stainless steel male buckle 18 and the rubber-coated stainless steel female buckle 19.

[0040] The relative misalignment between the rubber-wrapped stainless steel male buckle 18 and the rubber-wrapped stainless steel female buckle 19 in the prefabricated embedded steel-edged rubber waterstop 6 can accommodate the normal or tangential misalignment of the waterstop in the plane, without affecting the waterproof performance of the prefabricated embedded steel-edged rubber waterstop 6.

[0041] The scheme is further optimized by circumferentially setting pre-embedded steel pads 11 on the back surface of both the first lining concrete 22 and the second lining concrete 23. Several screws 12 are threaded through both pre-embedded steel pads 11. One end of the screw 12 extends into the first lining concrete 22 / second lining concrete 23, and the other end of the screw 12 passes through the pre-embedded steel pad 11 and the waterstop 10 and is threadedly connected to a nut 13. The connection between the screw 12 and the nut 13 is coated with quick-setting rubber asphalt waterproof spray coating 14.

[0042] Further optimization of the scheme: a polypropylene waterproof membrane 1 is laid on the bottom wall of the tunnel, and a reverse-adhesive quick-setting rubber asphalt waterproof coating 2 is sprayed on the side of the polypropylene waterproof membrane 1 away from the bottom wall of the tunnel; a waterproof mortar 16 is laid on the side wall of the tunnel, and a reverse-adhesive quick-setting rubber asphalt waterproof coating 2 is sprayed on the side of the waterproof mortar 16 away from the side wall of the tunnel; an SBS waterproof membrane 15 is laid on the top wall of the tunnel, and a quick-setting rubber asphalt waterproof coating 14 is sprayed on the side of the SBS waterproof membrane 15 away from the top wall of the tunnel; and an external rubber waterstop 3 is laid on the reverse-adhesive quick-setting rubber asphalt waterproof coating 2 and the quick-setting rubber asphalt waterproof coating 14 at the position corresponding to the expansion joint.

[0043] Further optimization of the plan includes the following steps:

[0044] Step 1: Determine the location of the expansion joint;

[0045] Step 2: Lay an external rubber waterstop at the expansion joint location;

[0046] Step 3: Erect templates on both sides of the expansion joint, pour the first lining concrete 22 and the second lining concrete 23, and embed both ends of the prefabricated embedded steel edge rubber waterstop 6 into the first lining concrete 22 and the second lining concrete 23 respectively.

[0047] Step 4: Install water collection box 9 in the expansion joint, and fix waterstop 10 circumferentially on the back water surface of the first lining concrete 22 and the second lining concrete 23, with waterstop 10 covering the expansion joint.

[0048] Step 5: Installation complete. Detailed implementation method:

[0050] Step 1: After the excavation of the open-cut tunnel foundation pit, pour the foundation pad and leveling layer, spray waterproof mortar 16 on the tunnel sidewall and smooth it, the thickness of the waterproof mortar 16 is 25cm. After the base leveling layer dries, clean the base leveling layer and remove any debris that may affect construction. Apply an additional layer of cement adhesive slurry prepared with cement and polypropylene adhesive. Before bonding, test-lay polypropylene waterproof membrane 1 (specifications: 800g, thickness: 1.5mm, width: 1500mm). Then, fold both ends of polypropylene waterproof membrane 1 and roll it up. Pour the prepared cement adhesive slurry onto the base leveling layer and spread it evenly with a scraper. Push polypropylene waterproof membrane 1 forward and promptly remove any air trapped between the polypropylene waterproof membrane 1 and the cement adhesive slurry with a scraper. Remove any excess cement adhesive slurry. The overlap of the long and short sides of polypropylene waterproof membrane 1 should be no less than 80mm. The joints of adjacent short sides of polypropylene waterproof membrane 1 should be staggered by more than 100cm. When laying double layers of polypropylene waterproof membrane 1, the wide sides should be staggered by 50cm.

[0051] Step 2: Using a pre-spraying reverse adhesion process, a reverse adhesion quick-setting rubber asphalt waterproof coating 2 is sprayed onto the polypropylene waterproof membrane 1 and waterproof mortar 16. The thickness of the reverse adhesion quick-setting rubber asphalt waterproof coating 2 is 2.0mm. The reverse adhesion quick-setting rubber asphalt waterproof coating 2 is a continuous and dense water-based polymer coating formed by the reaction of a liquid rubber emulsion (component A) composed of anionic rubber emulsion and nano-level asphalt emulsion with salt-exudated water emulsifier (component B). The materials of components A and B are atomized by spraying them through two nozzles in an airless spraying system (the airless spraying system is existing technology and will not be described in detail here). After being fully mixed, they instantly reach the substrate and, under the action of electrolytes, instantly demulsify, release water, coagulate into a film, and solidify to form a dense, continuous, and complete coating layer. Its peel strength with the post-poured concrete structure reaches 3.0N / mm, and its elongation at break is 1000%.

[0052] Step 3: Determine the location of the expansion joint. At the expansion joints on the tunnel floor and sidewalls, heat-weld and fix the external rubber waterstop 3 onto the reverse-adhesive quick-setting rubber asphalt waterproof spray coating 2. The external rubber waterstop 3 has a specification of 400mm × 8mm. At the expansion joints on the tunnel roof, cold-adhere and fix the external rubber waterstop 3 onto the quick-setting rubber asphalt waterproof spray coating 14. Erect a formwork for the first lining concrete 22 on one side of the expansion joint and lay the first reinforcing steel 24. Weld the steel edge strip 21 at the end of the rubber strip 17, which is connected to the rubber-coated stainless steel male buckle 18, to the first reinforcing steel 24. The rubber-coated stainless steel male buckle 18 extends into the expansion joint. Weld one of the pre-embedded steel pads 11 onto the first reinforcing steel 24, and then pour the first lining concrete 22. The rubber strip 17 is 450mm wide and 20mm thick. The rubber-coated stainless steel male buckle 18 has a diameter of 25mm.

[0053] Step 4: Erect the formwork for the second lining concrete 23 on the other side of the expansion joint and lay the second reinforcing bar 25. Weld the steel edge strip 21 at the end of the rubber strip 17, which is connected to the rubber-coated stainless steel female buckle 19, to the second reinforcing bar 25. The rubber-coated stainless steel female buckle 19 extends into the expansion joint and is axially connected to the rubber-coated stainless steel male buckle 18. Another pre-embedded steel pad 11 is welded to the second reinforcing bar 25, and then the second lining concrete 23 is poured. The second reinforcing bar 25 and the first reinforcing bar 24 are both pre-embedded in the tunnel lining on both sides of the expansion joint.

[0054] Step 5: Between the prefabricated steel-edged rubber waterstop 6 and the externally applied rubber waterstop 3, pour heated, semi-fluid asphalt mastic 4 (asphalt mastic is made of asphalt and mineral powder; it is solid at room temperature, but becomes a easily flowing liquid when heated to 180℃, making it easy to inject; it has good ductility and good seepage prevention effect, and can well adapt to large displacement and misalignment deformation of expansion joints). Embed resistance heating wires 5 within the asphalt mastic 4. The function of the resistance heating wires 5 is to heat the asphalt mastic 4... Heating is used to fill the expansion joint with asphalt mastic 4. After the asphalt mastic 4 is poured, the resistance heating wire 5 is de-energized. PE foam rods 7 (30mm in diameter) are pressed into the inside of the joint opening on the back side of the expansion joint to serve as a temporary seal and buffer. The semi-fluid asphalt mastic 4 after heating is poured between the prefabricated steel-edged rubber waterstop 6 and the PE foam rod 7, and the resistance heating wire 5 is embedded in the asphalt mastic 4. Finally, high-density polyurethane sealant 8 is filled between the PE foam rod 7 and the inside of the tunnel.

[0055] Step Six: After the first lining concrete 22 and the second lining concrete 23 reach the demolding strength, remove the formwork; use an airless spraying system to spray quick-setting rubber asphalt waterproof coating 14 (2.0mm thick) on the water-facing surfaces of the first lining concrete 22 and the second lining concrete 23, and then lay national standard type II SBS waterproof membrane 15 (4mm thick, 1000mm wide) on top of the quick-setting rubber asphalt waterproof coating 14.

[0056] Step 7: Install the water collection box 9 on the back side of the expansion joint. Secure the waterstop 10 to the back side of the first lining concrete 22 and the second lining concrete 23 using bolts 12 and nuts 13. Spray a quick-setting rubber asphalt waterproof coating 14 (2.0mm thick) at the joint between the bolts 12 and nuts 13. The waterstop 10 is preferably an Ω-type waterstop.

[0057] Expansion joints are crucial for coordinating uneven deformation in tunnels and are also the weakest link in tunnel waterproofing. The seepage prevention structure of expansion joints needs to withstand slip deformation while maintaining its waterproofing performance. However, the layout of the seepage prevention structures on the tunnel roof, floor, and sidewalls is inconsistent, resulting in significant differences in their ability to withstand slip deformation. This invention proposes a prefabricated, embedded steel-edged rubber waterstop 6 that withstands multi-directional slip deformation. It consists of two rubber strips 17 axially connected by a rubber-coated stainless steel male buckle 18 and a rubber-coated stainless steel female buckle 19. The two rubber strips 17 are respectively fixed to the first lining concrete 22 and the second lining concrete 23. The axially connected rubber-coated stainless steel male buckle 18 and rubber-coated stainless steel female buckle 19 connect the rubber strips 17. The rotation of the rings and the relative axial slip of the rubber-coated stainless steel male buckle 18 and rubber-coated stainless steel female buckle 19 can accommodate the normal or tangential slip deformation of the waterstop. The reverse-adhesive, quick-setting rubber asphalt waterproof spray coating 2 has an elongation at break of 1000% and a peel strength of 3.0 N / mm, allowing the polypropylene waterproof membrane 1 and SBS waterproof membrane 15 to tightly wrap the first lining concrete 22 and the second lining concrete 23, withstanding the large deformation of the expansion joint. The outermost part of the tunnel roof is covered by SBS waterproof membrane 15, the outermost part of the tunnel floor is covered by polypropylene waterproof membrane 1, and the outermost part of the tunnel sidewalls is covered by waterproof mortar 16. This avoids the problems of flexible waterproof membranes being not wear-resistant, which would lead to settlement and wear if used for waterproofing the outer walls of the sidewalls, and rigid waterproof mortar being prone to breakage when used as the load-bearing outer wall waterproofing of the roof and floor slabs.

[0058] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0059] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A seepage-proof structure for expansion joints in open-cut tunnels subjected to multi-directional displacement, characterized in that, include: A first lining concrete (22) and a second lining concrete (23) are poured on the inner sidewall of the tunnel along the tunnel length direction. An expansion joint is left between the first lining concrete (22) and the second lining concrete (23), and an anti-seepage structure is provided in the expansion joint. The seepage prevention structure includes an external rubber waterstop (3) circumferentially set on the inner wall of the tunnel. The external rubber waterstop (3) is located on the water-facing side of the first lining concrete (22) and the second lining concrete (23). The first lining concrete (22) and the second lining concrete (23) are both cast together with the external rubber waterstop (3). The expansion joint is provided with a prefabricated embedded steel edge rubber waterstop (6) in the inner circumference. The prefabricated embedded steel edge rubber waterstop (6) is located on the side of the external rubber waterstop (3) away from the back water surface. The two ends of the prefabricated embedded steel edge rubber waterstop (6) are respectively fixed in the first lining concrete (22) and the second lining concrete (23). A water collection box (9) is provided in the inner circumference of the expansion joint, and the water collection box (9) is close to the back water surface of the first lining concrete (22) and the second lining concrete (23); A waterstop (10) is circumferentially fixed to the back surface of the first lining concrete (22) and the second lining concrete (23), and the waterstop (10) is circumferentially arranged and covers the deformation joint. The prefabricated embedded steel-edged rubber waterstop (6) includes two circumferentially arranged rubber strips (17), one end of each rubber strip (17) is fixedly connected to a steel edge strip (21); the steel edge strip (21) of one of the rubber strips (17) is fixedly connected to the first lining concrete (22) by a first reinforcing bar (24), and the other end of the rubber strip (17) extends into the deformation joint and is fixedly connected to a rubber-coated stainless steel male buckle (18); the steel edge strip (21) of the other rubber strip (17) is connected to the first lining concrete (22) by a first reinforcing bar (24). The second reinforcing bar (25) is fixed in the second lining concrete (23). The other end of the rubber strip (17) extends into the deformation joint and is fixed with a rubber-coated stainless steel female buckle (19). The rubber-coated stainless steel male buckle (18) is axially inserted into the rubber-coated stainless steel female buckle (19) to form an axial socket connection. The rubber-coated stainless steel male buckle (18) and the rubber-coated stainless steel female buckle (19) can rotate relative to each other and move relative to each other along the axial direction. A water stop plug (20) is provided between the two. Both the backwater surfaces of the first lining concrete (22) and the second lining concrete (23) are provided with embedded steel pads (11) in the circumferential direction. Several screws (12) are passed through both embedded steel pads (11). One end of the screw (12) on the side of the first lining concrete (22) extends into the first lining concrete (22), and one end of the screw (12) on the side of the second lining concrete (23) extends into the second lining concrete (23). The other end of each screw (12) passes through the corresponding embedded steel pad (11) and the waterstop (10) and is threadedly connected to a nut (13). The connection between the screw (12) and the nut (13) is coated with quick-setting rubber asphalt waterproof spray coating (14).

2. The seepage prevention structure for expansion joints in open-cut tunnels subjected to multi-directional displacement as described in claim 1, characterized in that: The expansion joint is filled with asphalt mastic (4), the asphalt mastic (4) is located between the external rubber waterstop (3) and the water receiving box (9), and a resistance heating metal wire (5) is embedded in the asphalt mastic (4).

3. The seepage prevention structure for expansion joints in open-cut tunnels subjected to multi-directional displacement as described in claim 2, characterized in that: A PE foam rod (7) and a high-density polyurethane sealant (8) are circumferentially arranged between the water receiving box (9) and the asphalt mastic (4), with the high-density polyurethane sealant (8) close to the water receiving box (9).

4. The seepage prevention structure for expansion joints in open-cut tunnels subjected to multi-directional displacement as described in claim 1, characterized in that: Polypropylene waterproof membrane (1) is laid on the bottom wall of the tunnel. The side of the polypropylene waterproof membrane (1) away from the bottom wall of the tunnel is sprayed with reverse-adhesive quick-setting rubber asphalt waterproof coating (2). Waterproof mortar (16) is laid on the side wall of the tunnel. The side of the waterproof mortar (16) away from the side wall of the tunnel is sprayed with the reverse-adhesive quick-setting rubber asphalt waterproof coating (2). SBS waterproof membrane (15) is laid on the top wall of the tunnel. The side of the SBS waterproof membrane (15) away from the top wall of the tunnel is sprayed with quick-setting rubber asphalt waterproof coating (14). The external rubber waterstop (3) is laid on the reverse-adhesive quick-setting rubber asphalt waterproof coating (2) and the quick-setting rubber asphalt waterproof coating (14) at the position corresponding to the deformation joint.

5. A construction method for a seepage-proof structure for expansion joints in open-cut tunnels subjected to multi-directional displacement as described in any one of claims 1-4, characterized in that, Includes the following steps: Step 1: Determine the location of the expansion joint; Step 2: Lay the external rubber waterstop at the location of the expansion joint (3); Step 3: Erect a template for the first lining concrete (22) on one side of the expansion joint and lay the first reinforcing bar (24). Fix the steel edge strip (21) at the end of the rubber strip (17) connected to the rubber-coated stainless steel male buckle (18) to the first reinforcing bar (24), so that the rubber-coated stainless steel male buckle (18) extends into the expansion joint, and fix a pre-embedded steel pad (11) to the first reinforcing bar (24). Then pour the first lining concrete (22). Step 4: Erect a template for the second lining concrete (23) on the other side of the expansion joint and lay the second reinforcing bar (25). Fix the steel edge strip (21) at the end of the rubber strip (17) connected to the rubber-coated stainless steel female buckle (19) to the second reinforcing bar (25). Make the rubber-coated stainless steel female buckle (19) extend into the expansion joint and be axially connected to the rubber-coated stainless steel male buckle (18). Set the water stop plug (20) between the two and fix another pre-embedded steel pad (11) to the second reinforcing bar (25). Then pour the second lining concrete (23). Step 5: Install the water collection box (9) in the expansion joint, and fix the waterstop (10) circumferentially to the back surface of the first lining concrete (22) and the second lining concrete (23) through the screw (12) and the nut (13), so that the waterstop (10) covers the expansion joint, and apply the quick-setting rubber asphalt waterproof spray coating (14) at the connection between the screw (12) and the nut (13).

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