Three-dimensional continuous waterproof structure adaptive to assembly type subway station and construction technology of three-dimensional continuous waterproof structure

Abstract

The invention discloses a three-dimensional continuous waterproof structure adaptive to an assembly type subway station and a construction technology of the three-dimensional continuous waterproof structure, and belongs to the field of waterproofing between cast-in-place components and prefabricated components, and the three-dimensional continuous waterproof structure is arranged on a connecting end face of a prefabricated section and a cast-in-place section of the assembly type subway station and is arranged along the connecting end face in a whole ring mode to form a composite waterproof system; the composite waterproof system comprises an L-shaped rigid plate composite water stop belt, a grouting pipe, water stop glue and a sealing gasket which are sequentially arranged from the upstream face to the downstream face, and the short edge of the L-shaped rigid plate composite water stop belt is welded to the surface of a prefabricated section embedded steel plate in a waterproof mode. And the long edge of the L-shaped rigid plate composite waterstop extends into the cast-in-place section. By the adoption of the three-dimensional continuous waterproof structure adaptive to the fabricated subway station and the construction technology of the three-dimensional continuous waterproof structure, the aims of achieving multi-layer seepage prevention of the connecting end face, adapting to micro-deformation of the structure and improving the long-term durability are achieved, and the structural safety and the service life of the fabricated subway station are guaranteed.

Description

Technical Field

[0001] This invention relates to the field of waterproofing technology between cast-in-place and precast components, and particularly to a three-dimensional continuous waterproofing structure and its construction process adapted to prefabricated subway stations. Background Technology

[0002] Against the backdrop of the deepening policies on industrialized building and green construction of underground engineering, prefabricated underground structure technology has become a core promotion direction for underground engineering construction due to its ability to significantly improve project quality and construction efficiency. Among them, prefabricated subway stations, with their outstanding advantages such as short construction cycle, less on-site wet work, and precise and controllable component quality, have achieved large-scale application in subway construction and have become one of the mainstream forms of subway construction.

[0003] From a structural perspective, the main body of prefabricated subway stations adopts a hybrid structure of "prefabricated components + cast-in-place connecting sections": the prefabricated components include core components such as side walls, top slabs, bottom slabs, and central columns, with a single component weighing 30t-80t, requiring precise installation using specialized equipment; the cast-in-place connecting sections serve as the splicing and transition between prefabricated components, such as the corner connection between side walls and top slabs, and the filling of gaps between adjacent prefabricated bottom slabs, etc. Their width is usually 200mm-500mm, which is not only a key force transmission area for structural stress, but also a core weak link for waterproofing and seepage prevention.

[0004] With the widespread application of prefabricated subway stations, the waterproofing performance of the connection points between precast components and cast-in-place sections directly determines the seepage prevention safety of the entire station structure. Practical data shows that most leakage problems in current prefabricated subway stations are concentrated at these connection points: leakage not only leads to equipment damage such as short circuits in electrical cabinets and communication system failures, but corrosive media such as chloride ions and sulfates in groundwater also accelerate steel corrosion, severely weakening the structural load-bearing capacity and drastically shortening the originally designed 100-year structural lifespan to less than 50 years. Therefore, developing waterproofing technologies for connection points adapted to the characteristics of prefabricated subway stations has become a core requirement for ensuring project safety and improving structural durability, and a key bottleneck in promoting the further popularization of prefabricated underground structure technology.

[0005] Currently, the waterproofing solutions for the connection parts of prefabricated subway stations still rely on single waterstops and conventional grouting pipes as core components. These solutions are difficult to adapt to the complex actual working conditions of underground engineering, such as multi-directional stress, structural micro-deformation, and high water levels. As a result, the potential for leakage has not been effectively resolved for a long time.

[0006] Specifically, the following defects exist: First, the waterstop is easily affected by structural stress and environmental deformation, resulting in debonding or joint cracking at the concrete interface, and its water pressure resistance is weak; second, the grouting pipe can only be used for passive repair after leakage, and it is easily blocked by foreign objects during cast-in-place construction and loses its function; third, in key areas such as the sealing of tension holes, the sealing of steel bar anchorages, and the treatment of the interface of cast-in-place transition sections, the existing process often results in gaps due to incomplete treatment, leading to discontinuity in the waterproofing system; fourth, the existing scheme has poor adaptability to the installation deviation of precast components, further exacerbating the risk of waterproofing failure.

[0007] In summary, existing waterproofing technologies can no longer meet the core requirements of long-term impermeability, deformation adaptability, controllable construction, and durability at joints. Summary of the Invention

[0008] The purpose of this invention is to provide a three-dimensional continuous waterproof structure and its construction process suitable for prefabricated subway stations, thereby solving the above-mentioned technical problems.

[0009] To achieve the above objectives, the present invention provides a three-dimensional continuous waterproof structure adapted to prefabricated subway stations. The three-dimensional continuous waterproof structure is set at the connection end face of the prefabricated section and the cast-in-place section of the prefabricated subway station, and is arranged in a whole ring along the connection end face to form a composite waterproof system. The composite waterproofing system includes an L-shaped rigid plate composite waterstop, a grouting pipe, a waterstop adhesive, and a sealing gasket, arranged sequentially from the water-facing side to the back side. The short side of the L-shaped rigid plate composite waterstop is welded to the surface of a precast section via a waterproof weld, ensuring a tight fit with the end face of the precast section to block the seepage path on the water-facing side. The long side of the L-shaped rigid plate composite waterstop extends into the cast-in-place section, is tied and fixed to the reinforcing steel bars, and is then encased in cast-in-place concrete to form a physical seepage barrier. This, combined with the elastic sealing of the waterstop adhesive and the active leak repair of the grouting pipe, forms a dual anti-seepage structure that combines active blocking with passive remediation.

[0010] Preferably, the L-shaped rigid plate composite waterstop has a width of 240mm, a thickness of 3mm, a short side length of 40mm, and a long side length of 200mm. The joints of the L-shaped rigid plate composite waterstop are fully welded, and the outside of the weld is wrapped with water-swellable rubber tape. The rigid plate in the L-shaped rigid plate composite waterstop is a galvanized steel plate. L-shaped rigid plate composite waterstop is adapted to the corner of precast components through bending treatment to tolerate a flatness deviation of 3mm-5mm on the end face of the precast section.

[0011] Preferably, the tension holes on both sides of the precast section are sealed with micro-expansion concrete, the threaded steel is sealed with water-swellable rubber, the anchor head is sealed with water-swellable rubber, and the short side of the pre-embedded steel plate and L-shaped rigid plate composite waterstop on the end face of the precast section is welded with impermeable material. Water-swellable rubber rings are fitted at the anchorage of the precast steel bars, and the coverage of the water-swellable rubber rings overlaps with that of the L-shaped rigid plate composite waterstop. Water-swellable rubber blocks are laid on the outside of the anchor head at the anchorage of the steel bars and covered with stainless steel cover plates. The gaps at the edges of the stainless steel cover plates are filled with sealant, and the edges of the stainless steel cover plates wrap around the long side of the L-shaped rigid plate composite waterstop.

[0012] Preferably, the grouting pipes are laid out in a complete ring along the connection end face for later injection of waterproof grout to fill potential gaps.

[0013] Preferably, the short side of the L-shaped rigid plate composite waterstop is welded to the embedded steel plate through impermeable welding. The embedded steel plate is a galvanized steel plate with a width of 50mm and a thickness of 3mm.

[0014] Preferably, the precast concrete is made of the same grade of micro-expansion concrete as the cast-in-place concrete to ensure the integrity of the structure, the continuity of stress transmission and durability, and to avoid stress concentration cracking due to strength differences. Ultimately, after casting, it tightly wraps with the long side of the L-shaped rigid plate composite waterstop to form a rigid bond.

[0015] Preferably, a water-stop adhesive is continuously laid on the connection end face of the precast section and the cast-in-place section to form a continuous gel-like sealing layer. A sealing gasket is laid on the back side of the gel-like sealing layer to fill the gap.

[0016] The construction method for a three-dimensional continuous waterproof structure suitable for prefabricated subway stations includes the following steps: S1. Pre-treatment of the end face of the prefabricated section; S11. Remove laitance, rust, debris and oil stains from the connection end face between the precast section and the cast-in-place section to ensure that there are no contaminants attached to the connection end face; S12. Check the flatness of the precast section end face, grind the protruding parts, and control the flatness deviation of the end face within the range of 3mm-5mm to meet the bonding requirements of the L-shaped rigid plate composite waterstop. S13. Clean the residual debris inside the tensioning holes on both sides of the precast section to ensure that the inner wall of the hole is dry in preparation for subsequent sealing. S2 and L-shaped rigid plate composite waterstop strip installation and fixing; S21. Based on the dimensions of the corner of the precast component, the L-shaped rigid plate composite waterstop is bent to fit the corner curvature. S22. The short side of the L-shaped rigid plate composite waterstop is attached to the embedded steel plate on the end face of the precast section after treatment. The short side is fixed to the surface of the embedded steel plate of the precast section by waterproof welding to ensure that the short side is tightly attached to the end face of the precast section without gaps. S23. Tie the long side of the L-shaped rigid plate composite waterstop to the pre-set steel bars of the cast-in-place section to prevent the waterstop from shifting during concrete pouring. S24. Full welding is performed on the joints of the L-shaped rigid plate composite waterstop arranged in a ring. After the weld is completed, water-swellable rubber tape is wrapped around the outside to ensure that the joint is sealed without any leakage or breakpoints. S3. Layout of waterproof auxiliary components; S31 is laid out in a ring along the end face connecting the precast section and the cast-in-place section. It is fixed with L-shaped rigid plate composite waterstop by tie straps or brackets to avoid displacement and blockage during pouring. S32. Apply waterproof adhesive evenly to the entire ring of the connecting end face to form a continuous adhesive sealing layer. S33 lays a sealing gasket in a full ring on the back side of the water-stop adhesive to ensure that the sealing gasket is tightly attached to the water-stop adhesive without wrinkles or gaps, thus achieving flexible sealing and supplementation. S4. Cast-in-place section with micro-expansion concrete pouring; S41. Prepare micro-expansion concrete that is compatible with the strength grade of precast concrete components, and control the concrete mix proportion to meet the shrinkage requirements. S42. Micro-expansion concrete is poured into the cast-in-place section in layers. During the pouring process, the area around the L-shaped rigid plate composite waterstop is vibrated to ensure that the micro-expansion concrete tightly wraps the long side of the L-shaped rigid plate composite waterstop without air bubbles or gaps, forming a rigid bond. S5. Curing of cast-in-place concrete: After the cast-in-place concrete is poured, cover and keep it moist for curing, and continue curing until the concrete reaches the design strength grade. S6. Grouting pipe repair; S61. After the concrete curing is completed, check the unobstructedness of each grouting pipe, remove any blocked grouting pipes and replace or unclog them. S62. Prepare a waterproof grout suitable for micro-expansion concrete used for sealing tension holes; S63. Inject waterproof grout into the connection between the precast section and the cast-in-place section through the grouting pipe. When there is uniform grout overflow at the outlet end of the grouting pipe and the pressure is stable, stop grouting through the grouting pipe. Complete the grouting operation of all grouting pipes in the whole ring in sequence to form an active seepage prevention and replenishment.

[0017] Therefore, the present invention, employing the above-mentioned three-dimensional continuous waterproof structure and construction process adapted to prefabricated subway stations, has the following beneficial effects: 1. More Reliable Seepage Resistance: Breaking through the limitations of existing technologies that rely on single waterstops or passive grouting pipes, this system constructs a multi-component collaborative system consisting of galvanized steel composite waterstops, waterstop adhesive, sealing gaskets, and grouting pipes. This forms a multi-layered seepage prevention defense line combining rigid blocking, flexible adaptation, and active remediation. The galvanized steel composite waterstop, with its high rigidity, can directly resist groundwater pressure and structural stress, blocking major seepage channels. The waterstop adhesive and sealing gasket adapt to tiny gaps at their interface, preventing the rigid components from detaching from the concrete. The grouting pipes can fill potential voids later. Compared to existing single-defense systems, this system offers more comprehensive seepage resistance, effectively addressing complex underground conditions and significantly reducing the risk of leakage at connection points. 2. Enhanced Continuity of the Waterproofing System: Through the complete ring arrangement of galvanized steel plate composite waterstops and the full welding treatment of the joints, with additional water-swellable rubber tape wrapped around the welds, leakage due to joint cracking is prevented. At the same time, thanks to the series effect of the steel plate waterstops, key parts such as tension holes, anchor heads, and cast-in-place transition sections are seamlessly connected to the overall waterproofing system. After the tension holes are sealed, they are connected to the steel plate waterstops with sealant. The anchorage of the reinforcing bars overlaps with the coverage area of ​​the steel plate waterstops through water-swellable rubber rings. The cast-in-place concrete tightly wraps the long side of the steel plate waterstops, completely eliminating the sealing defects and protection breaks in key parts in existing technologies, and achieving continuous protection from the water-facing side to the back side. 3. Superior Durability: The waterstop is made of galvanized steel plate, whose galvanized layer can effectively isolate corrosive media such as chloride ions and sulfates in groundwater, preventing the steel plate from rusting. Moreover, the anti-aging performance of the steel plate material is far superior to that of traditional rubber waterstops. At the same time, it is combined with durable materials such as micro-expansion concrete and water-swellable rubber, so that the design life of the waterproof system matches the 100-year structural life of the subway station. This solves the problems of easy aging of rubber waterstops and easy corrosion of ordinary steel plates, which lead to short life of waterproof system and frequent maintenance and replacement, significantly extending the service life of the waterproof system. 4. More flexible construction adaptability: The galvanized steel composite waterstop adopts an L-shaped structure design (40mm short side, 200mm long side), which can be bent to adapt to the corner of the precast component and can tolerate a flatness deviation of 3mm-5mm on the end face of the precast section, and can be attached without forced compression; during installation, the short side is welded to the precast section through waterproof welding, and the long side is tied and fixed to the reinforcing steel of the cast-in-place section, which can resist the lateral pressure of concrete pouring and the impact of vibrator, avoiding the problems of easy displacement and damage of existing waterstops; the overall process is simplified, the compatibility with construction deviations is high, the difficulty of operation and the impact of on-site construction errors on the waterproof effect are reduced, and the construction efficiency and quality stability are improved at the same time. 5. More convenient and economical maintenance: The grouting pipes are laid out in the entire ring in the composite waterproofing system, forming a "protection-remediation" linkage mechanism with the galvanized steel composite waterstop. If minor leakage occurs later, there is no need to chisel open the surface of the structure (avoiding the risk of secondary leakage). The gaps can be filled simply by injecting waterproof grout through the grouting pipes, achieving rapid repair, greatly reducing maintenance costs and repair difficulty, and solving the problems of difficult and costly repair of traditional waterproof components.

[0018] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0019] Figure 1 This is a structural diagram of the three-dimensional continuous waterproof structure adapted to prefabricated subway stations according to the present invention; Figure 2 This is a diagram illustrating the sealing and waterproofing of tension holes in a three-dimensional continuous waterproof structure adapted to prefabricated subway stations according to the present invention. Figure 3 This is a waterproof diagram of the end anchor head of the three-dimensional continuous waterproof structure adapted to prefabricated subway stations according to the present invention; Figure 4 This is a structural diagram as described in Embodiment 1 of the present invention; Figure 5 This is a structural diagram as described in Embodiment 2 of the present invention; Figure 6 This is a structural diagram as described in Embodiment 3 of the present invention; Figure 7 This is a structural diagram as described in Embodiment 4 of the present invention. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the embodiments of the present invention and are not intended to limit the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of this application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout.

[0021] It should be noted that the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, such as a process, method, system, product, or server that includes a series of steps or units, not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such process, method, product, or device.

[0022] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0023] like Figures 1-3 As shown, a three-dimensional continuous waterproof structure adapted to prefabricated subway stations is installed at the connection end face between the prefabricated and cast-in-place sections of the prefabricated subway station, forming a composite waterproof system along the entire ring of the connection end face. The composite waterproof system includes an L-shaped rigid plate composite waterstop, a grouting pipe, a waterstop adhesive, and a sealing gasket, arranged sequentially from the water-facing side to the back side. The short side of the L-shaped rigid plate composite waterstop is welded to the surface of the prefabricated section's embedded steel plate through impermeable welding, and is tightly fitted to the end face of the prefabricated section without gaps to block the seepage path on the water-facing side. The long side of the L-shaped rigid plate composite waterstop extends into the interior of the cast-in-place section, is tied and fixed with the reinforcing steel of the cast-in-place section, and is then wrapped by the cast-in-place concrete to form a physical seepage barrier. At the same time, it works in conjunction with the elastic sealing of the waterstop adhesive and the active leak repair of the grouting pipe to form a dual seepage-proof structure that combines active blocking with passive remediation. This prevents the waterstop from shifting or deforming, compensates for the shortcomings of existing single waterstops such as easy detachment and weak water pressure resistance, and improves the overall seepage-proof performance of the connection.

[0024] The L-shaped rigid plate composite waterstop has a width of 240mm, a thickness of 3mm, a short side length of 40mm, and a long side length of 200mm. The joints of the L-shaped rigid plate composite waterstop are fully welded, and the outside of the weld is wrapped with water-swellable rubber tape to eliminate the cracking of existing waterstop joints and the protective breaks caused by the intermittent layout of grouting pipes. The rigid plate in the L-shaped rigid plate composite waterstop is made of galvanized steel plate. The L-shaped rigid plate composite waterstop is adapted to the corner of the precast component through bending treatment to tolerate a flatness deviation of 3mm-5mm on the end face of the precast section.

[0025] The tension holes on both sides of the precast section are sealed with micro-expansion concrete, the threaded steel is sealed with water-swellable rubber, the anchor head is sealed with water-swellable rubber, and the short side of the pre-embedded steel plate and L-shaped rigid plate composite waterstop on the end face of the precast section is welded with impermeable weld. A water-swellable rubber ring is fitted at the anchorage of the precast steel reinforcement, overlapping the coverage area of ​​the water-swellable rubber ring with that of the L-shaped rigid plate composite waterstop. A water-swellable rubber block is laid on the outside of the anchor head at the steel reinforcement anchorage and covered with a stainless steel cover plate. Sealant is injected into the gaps at the edges of the stainless steel cover plate, and the edges of the stainless steel cover plate wrap around the long side of the L-shaped rigid plate composite waterstop. At the steel reinforcement anchorage, the L-shaped rigid plate composite waterstop and the water-swellable rubber block work together, utilizing the rigid support of the L-shaped rigid plate composite waterstop to ensure a tight fit between the rubber, the steel reinforcement, and the precast section, solving the problem of uneven joints left by manual wrapping. In the cast-in-place transition section, the L-shaped rigid plate composite waterstop connects the precast end face to the cast-in-place concrete, strengthening the interface adhesion and reducing debonding and leakage caused by incomplete roughening.

[0026] Grouting pipes are laid out in a ring along the connection end face for later injection of waterproof grout to fill potential gaps.

[0027] The short side of the L-shaped rigid plate composite waterstop is welded to the embedded steel plate through impermeable welding. The embedded steel plate is a galvanized steel plate with a width of 50mm and a thickness of 3mm.

[0028] The precast section uses the same grade of micro-expansion concrete as the cast-in-place section, so that after pouring, it can be tightly wrapped with the long side of the L-shaped rigid plate composite waterstop to form a rigid bond.

[0029] Water-stop adhesive is continuously laid on the connection end face of the precast section and the cast-in-place section to form a continuous ring of gel-like sealing layer. A sealing gasket is laid on the back side of the gel-like sealing layer to fill the gap.

[0030] The construction method for a three-dimensional continuous waterproof structure suitable for prefabricated subway stations includes the following steps: S1. Pre-treatment of the end face of the prefabricated section; S11. Remove laitance, rust, debris and oil stains from the connection end face between the precast section and the cast-in-place section to ensure that there are no contaminants attached to the connection end face; S12. Check the flatness of the precast section end face, grind the protruding parts, and control the flatness deviation of the end face within the range of 3mm-5mm to meet the bonding requirements of the L-shaped rigid plate composite waterstop. S13. Clean the residual debris inside the tensioning holes on both sides of the precast section to ensure that the inner wall of the hole is dry in preparation for subsequent sealing. S2 and L-shaped rigid plate composite waterstop strip installation and fixing; S21. Based on the dimensions of the corner of the precast component, the L-shaped rigid plate composite waterstop is bent to fit the corner curvature. S22. The short side of the L-shaped rigid plate composite waterstop is attached to the embedded steel plate on the rear end face of the precast section. The short side is fixed to the surface of the embedded steel plate of the precast section by impermeable welding to ensure that the short side is tightly attached to the end face of the precast section without gaps. S23. Tie the long side of the L-shaped rigid plate composite waterstop to the pre-set steel bars of the cast-in-place section to prevent the waterstop from shifting during concrete pouring. S24. Full welding is performed on the joints of the L-shaped rigid plate composite waterstop arranged in a ring. After the weld is completed, water-swellable rubber tape is wrapped around the outside to ensure that the joint is sealed without any leakage or breakpoints. S3. Layout of waterproof auxiliary components; S31 is laid out in a ring along the end face connecting the precast section and the cast-in-place section. It is fixed with L-shaped rigid plate composite waterstop by tie straps or brackets to avoid displacement and blockage during pouring. S32. Apply waterproof adhesive evenly to the entire ring of the connecting end face to form a continuous adhesive sealing layer. S33 lays a sealing gasket in a full ring on the back side of the water-stop adhesive to ensure that the sealing gasket is tightly attached to the water-stop adhesive without wrinkles or gaps, thus achieving flexible sealing and supplementation. S4. Cast-in-place section with micro-expansion concrete pouring; S41. Prepare micro-expansion concrete that is compatible with the strength grade of precast concrete components, and control the concrete mix proportion to meet the shrinkage requirements. S42. Micro-expansion concrete is poured into the cast-in-place section in layers. During the pouring process, the area around the L-shaped rigid plate composite waterstop is vibrated to ensure that the micro-expansion concrete tightly wraps the long side of the L-shaped rigid plate composite waterstop without air bubbles or gaps, forming a rigid bond. S5. Curing of cast-in-place concrete: After the cast-in-place concrete is poured, cover and keep it moist for curing, and continue curing until the concrete reaches the design strength grade. S6. Grouting pipe repair; S61. After the concrete curing is completed, check the unobstructedness of each grouting pipe, remove any blocked grouting pipes and replace or unclog them. S62. Prepare a waterproof grout suitable for micro-expansion concrete used for sealing tension holes; S63. Inject waterproof grout into the connection between the precast section and the cast-in-place section through the grouting pipe. When there is uniform grout overflow at the outlet end of the grouting pipe and the pressure is stable, stop grouting through the grouting pipe. Complete the grouting operation of all grouting pipes in the whole ring in sequence to form an active seepage prevention and replenishment.

[0031] To further illustrate the present invention, the following embodiments are provided.

[0032] Example 1: Waterproofing implementation at the top of the interface between the cast-in-place section and the precast section (e.g.) Figure 4 (as shown) The specific implementation steps are as follows: Pre-treatment of the top end face of the precast and cast-in-place sections: Remove laitance, rust, and debris from the top end face of the precast section and the reserved area of ​​the top slab of the cast-in-place section, and grind the end face until the flatness deviation is ≤5mm; seal the tensioning hole at the top of the precast section with micro-expansion concrete according to the requirements of this invention, use water-swellable rubber to seal the threaded steel, use water-swellable rubber to seal the anchor head, and use impermeable welding for the short side of the composite waterstop strip of the pre-embedded steel plate and L-shaped galvanized steel plate on the end face to ensure no gaps.

[0033] Installation of L-shaped galvanized steel composite waterstop: Select a 240mm wide and 3mm thick L-shaped galvanized steel composite waterstop (40mm short side, 200mm long side), and adapt it to the top corner curvature by bending. The short side is welded to the pre-embedded steel plate (50mm wide and 3mm thick) on the top end face of the precast section using a waterproof weld. The long side is tied and fixed to the reinforcing steel of the cast-in-place section top slab, and the joint is fully welded. The outside of the weld is wrapped with water-swellable rubber tape.

[0034] Layout of composite waterproof components: Layout in the following order: steel plate waterstop → grouting pipe → waterstop adhesive → sealing gasket: The grouting pipe is laid out in a complete ring along the top interface and is fixed with the steel plate waterstop to ensure that it does not shift during pouring; Water-swellable waterstop adhesive is applied to the inside of the sealing gasket in a complete ring to fill the small gaps between the sealing gasket and the end face; Waterproof elastic sealing gasket is laid, which is tightly attached to the waterstop adhesive without wrinkles.

[0035] Coordinated construction of top waterproofing layer: Before the construction of the cast-in-place section top slab, extend the self-adhesive roll waterproofing layer and coating waterproofing layer to the surface of the precast section, with an extension length of not less than 1m; fix the end at the joint between the waterproofing layer and the sealing gasket, and seal it with sealant; set an 80×50mm water collection box below the rebar connector to drain a small amount of leaked water.

[0036] Cast-in-place section pouring and curing: The top slab of the cast-in-place section is poured in layers using micro-expansion concrete with strength compatible with the precast components. The area around the steel plate waterstop is vibrated to ensure that the concrete tightly wraps the long side of the waterstop. After pouring, the concrete is kept moist and cured according to the specifications until it reaches the design strength.

[0037] Grouting and replenishment: After curing, check the patency of the grouting pipe, inject waterproof grout that is compatible with micro-expansion concrete until the grout overflows evenly and the pressure is stable, thus completing the active seepage prevention and replenishment.

[0038] A three-dimensional composite waterproofing system: Currently, most subway stations are located in water-rich environments with high groundwater levels. A composite waterproofing system with galvanized steel plate waterstops as the core and supporting construction techniques can overcome the shortcomings of existing technologies that rely on single waterstops or passive grouting pipes, such as insufficient impermeability, poor sealing continuity, low durability, and weak construction adaptability. The galvanized steel plate waterstop, with its high rigidity, can directly resist groundwater pressure and structural stress, blocking the main seepage channels. At the same time, it can further fill potential gaps through grouting pipes. Compared with a single defense system, it has more comprehensive impermeability and more effectively meets the requirements of long-term impermeability, reliability, and durability of the structure.

[0039] Service life prediction: The structural design and construction meet the relevant specifications and requirements. The waterproofing system adopts the comprehensive protection principle of "prevention first, combined with drainage". During the operation period, convenient post-repair can be achieved through pre-installed grouting pipes. It works in conjunction with the main structure of the subway and provides mutual protection. It is expected that its service life will meet the design service life of 100 years of the main structure.

[0040] Improved construction efficiency and reduced maintenance costs: This structure incorporates pre-installed grouting pipes within the waterproofing system, forming a "protection-remediation" linkage with the galvanized steel plate waterstop. The rigid support of the steel plate waterstop helps position components such as the grouting pipes and waterstop sealant, preventing displacement and damage of auxiliary components during construction, reducing construction difficulty, and improving construction efficiency and quality stability. If minor leaks occur later, there is no need to damage the structure; simply injecting waterproof grout through the grouting pipes can fill the gaps. Combined with the long-lasting protection of the steel plate waterstop, compared to the need to chisel open the surface of the structure for positioning and repair after leakage, the repair cost is lower and the efficiency is higher, overcoming the problems of difficult and costly repair of general waterproofing components.

[0041] Example 2: Waterproofing implementation at the bottom and sidewalls of the interface between the precast and cast-in-place sections (e.g.) Figure 5 (as shown) The specific implementation steps are as follows: Bottom foundation pretreatment: Clean the bottom end face of the precast section and the surface of the concrete of the bottom slab of the cast-in-place section to ensure that the slab is flat and clean; lay a non-pre-laid waterproof membrane on the concrete of the slab, extending to the edge of the bottom end face of the precast section, and fix the end with a pressure strip and inject sealant.

[0042] Side wall enclosure treatment: Roughen the surface of the enclosure structure corresponding to the side wall, apply cement-based penetrating crystalline waterproof coating, and cover the area where the steel plate waterstop is installed to ensure the connection between the enclosure structure and the waterproof system.

[0043] Installation of L-shaped galvanized steel composite waterstop: Bottom: Use L-shaped galvanized steel composite waterstop. The short side (40mm) is welded to a 50mm wide embedded steel plate on the bottom face of the precast section through impermeable welding. The long side (200mm) extends into the cast-in-place bottom slab concrete and is tied and fixed to the bottom slab reinforcement. Side wall: The waterstop is bent to match the corner curvature of the side wall and the bottom. The short side is fixed to the side wall face of the precast section, and the long side is tied to the side wall reinforcement. The joint is fully welded and wrapped with water-swellable rubber tape. The bottom and side wall waterstops are continuously connected without any breaks in the entire ring.

[0044] Composite waterproofing component installation: Grouting pipes are installed in a complete ring along the bottom and side walls. The bottom grouting pipes are fixed above the waterproofing layer of the foundation, and the side wall grouting pipes are bound to the steel plate waterstop. Water-swellable sealing adhesive is applied to the bottom and side wall end faces, and the sealing adhesive in the side wall area is connected to the waterproof coating of the enclosure structure. A 1.5mm thick double-sided self-adhesive butyl rubber roll is laid at the bottom as a reinforcing layer, overlapping and adhering to the sealing gasket. Waterproof elastic sealing gaskets are laid on the side walls, and the termination is... Figure 6 It must be fixed and sealed.

[0045] Special treatment for steel bar anchorage: At the steel bar anchorages on the side walls and bottom, water-swellable rubber rings are fitted (overlapping with the coverage area of ​​the steel plate waterstop), water-swellable rubber blocks are laid on the anchor heads and covered with stainless steel cover plates, and sealant is injected around the cover plates, with the edges adhering to the long side of the steel plate waterstop.

[0046] Cast-in-place section pouring and curing: The bottom and side walls are poured in layers using micro-expansion concrete. When pouring the bottom, avoid disturbing the waterproof layer of the foundation. When pouring the side walls, focus on vibrating the area between the steel plate waterstop and the retaining structure to ensure compaction. After pouring, keep the concrete moist and cure until the design strength.

[0047] Grouting: Waterproof grout is injected through grouting pipes to fill potential gaps between the bottom bedding layer and concrete, and between the side walls and the enclosure structure, thus completing the seepage prevention and repair.

[0048] A three-dimensional composite waterproofing system: Currently, most subway stations are located in water-rich environments with high groundwater levels. A composite waterproofing system with galvanized steel plate waterstops as the core and supporting construction techniques can overcome the shortcomings of existing technologies that rely on single waterstops or passive grouting pipes, such as insufficient impermeability, poor sealing continuity, low durability, and weak construction adaptability. The galvanized steel plate waterstop, with its high rigidity, can directly resist groundwater pressure and structural stress, blocking the main seepage channels. At the same time, it can further fill potential gaps through grouting pipes. Compared with a single defense system, it has more comprehensive impermeability and more effectively meets the requirements of long-term impermeability, reliability, and durability of the structure.

[0049] Service life prediction: The structural design and construction meet the relevant specifications and requirements. The waterproofing system adopts the comprehensive protection principle of "prevention first, combined with drainage". During the operation period, convenient post-repair can be achieved through pre-installed grouting pipes. It works in conjunction with the main structure of the subway and provides mutual protection. It is expected that its service life will meet the design service life of 100 years of the main structure.

[0050] Improved construction efficiency and reduced maintenance costs: This structure incorporates pre-installed grouting pipes within the waterproofing system, forming a "protection-remediation" linkage with the galvanized steel plate waterstop. The rigid support of the steel plate waterstop helps position components such as the grouting pipes and waterstop sealant, preventing displacement and damage of auxiliary components during construction, reducing construction difficulty, and improving construction efficiency and quality stability. If minor leaks occur later, there is no need to damage the structure; simply injecting waterproof grout through the grouting pipes can fill the gaps. Combined with the long-lasting protection of the steel plate waterstop, compared to the need to chisel open the surface of the structure for positioning and repair after leakage, the repair cost is lower and the efficiency is higher, overcoming the problems of difficult and costly repair of general waterproofing components.

[0051] Example 3: Waterproofing implementation at the top of the entrance / exit interface of the prefabricated section of the auxiliary structure (e.g.) Figure 6 (as shown) The specific implementation steps are as follows: Top pretreatment of the interface: Clean the dust and debris from the top end face of the precast section entrance and exit and the contact surface of the retaining structure, and apply sealant chamfer treatment (30×30mm) to the joint between the retaining structure and the interface; the tensioning hole at the top of the precast section entrance and exit is sealed with micro-expansion concrete according to the requirements of this invention, the threaded steel is sealed with water-swellable rubber, and the anchor head is sealed with water-swellable rubber.

[0052] Customized installation of L-shaped galvanized steel composite waterstop: Based on the angle between the top of the entrance / exit and the enclosure structure, the 240mm wide and 3mm thick L-shaped galvanized steel composite waterstop is bent to ensure the fit between the short side and the end face of the precast section, and the long side and the cast-in-place concrete section. The short side is welded to the pre-embedded steel plate (50mm wide and 3mm thick) on the top end face of the precast section with impermeable welding. The long side is tied to the top reinforcement of the cast-in-place section. The joint is fully welded and wrapped with water-swellable rubber tape. The entire ring covers the entire cross-section of the top of the entrance / exit.

[0053] Waterproof reinforcement layer and composite component layout: A waterproof reinforcement layer is laid on the top end face of the prefabricated section entrance (connected with the self-adhesive roll waterproof layer and coating waterproof layer). The installation sequence is as follows: steel plate waterstop → grouting pipe → waterstop adhesive → sealing gasket. The grouting pipe is laid out in a complete ring along the top (5m-6m spacing), staggered from the water collection box (set on the top of the side wall, specification 80×50mm). Water-swellable waterstop adhesive is applied to the inside of the sealing gasket, and seamlessly connected with the sealant of the enclosure structure by bevel. After the sealing gasket is laid, it is pressed firmly and there is no looseness.

[0054] Waterproofing layer termination treatment: The self-adhesive waterproofing membrane is returned to the surface of the precast component and sealed. The termination is fixed with a pressure strip and sealant is injected to ensure a continuous seal with the sealing gasket and water-stopping adhesive.

[0055] Cast-in-place section pouring and curing: Micro-expansion concrete is used to pour the top of the entrance and exit section. The key area for vibration is the area where the steel plate waterstop connects with the retaining structure and the waterproof reinforcement layer to avoid air bubbles or gaps. After pouring, curing is carried out in accordance with the specifications to ensure that the concrete is tightly bonded to the waterstop and the retaining structure.

[0056] Grouting and filling: After curing, check the patency of the grouting pipe, inject waterproof grout, and focus on filling the tiny gaps between the waterproof reinforcement layer and the concrete to achieve active seepage prevention.

[0057] Service life prediction: The structural design and construction meet the relevant specifications and requirements. The waterproofing system adopts the comprehensive protection principle of "prevention first, combined with drainage". During the operation period, convenient post-repair can be achieved through pre-installed grouting pipes. It works in conjunction with the main structure of the subway and provides mutual protection. It is expected that its service life will meet the design service life of 100 years of the main structure.

[0058] Improved construction efficiency and reduced maintenance costs: This structure incorporates pre-installed grouting pipes within the waterproofing system, forming a "protection-remediation" linkage with the galvanized steel plate waterstop. The rigid support of the steel plate waterstop helps position components such as the grouting pipes and waterstop sealant, preventing displacement and damage of auxiliary components during construction, reducing construction difficulty, and improving construction efficiency and quality stability. If minor leaks occur later, there is no need to damage the structure; simply injecting waterproof grout through the grouting pipes can fill the gaps. Combined with the long-lasting protection of the steel plate waterstop, compared to the need to chisel open the surface of the structure for positioning and repair after leakage, the repair cost is lower and the efficiency is higher, overcoming the problems of difficult and costly repair of general waterproofing components.

[0059] Example 4: Waterproofing implementation at the bottom of the entrance / exit interface of the prefabricated section of the auxiliary structure (e.g.) Figure 7 (as shown) The specific implementation steps are as follows: Bottom foundation and interface pretreatment: Pour the foundation concrete and level it to ensure that the surface flatness deviation is ≤5mm; lay a non-pre-laid waterproof membrane on the foundation, extending to the bottom edge of the precast section entrance and exit, and seal the end with sealant (fix the end firmly); clean the laitance and debris from the bottom edge of the precast section and grind it to meet the requirements for waterstop bonding.

[0060] Installation of L-shaped galvanized steel composite waterstop: Select a 240mm wide and 3mm thick L-shaped galvanized steel composite waterstop (40mm short side, 200mm long side). The short side is welded to the pre-embedded steel plate (50mm wide, 3mm thick) at the bottom end of the precast section entrance and exit through a watertight weld. The long side extends into the bottom concrete of the cast-in-place section and is tied and fixed to the bottom reinforcement. The waterstop joint is fully welded and wrapped with water-swellable rubber tape, covering the bottom interface of the entrance and exit in a complete ring.

[0061] Connection between composite waterproof components and roll material: Grouting pipes are laid out along the bottom ring at intervals of 5m-6m, fixed above the non-pre-laid roll waterproof layer, and auxiliaryly bound to the steel plate waterstop; water-swellable sealing adhesive is applied along the bottom end face in a ring, connecting with the sealant at the roll end to form a continuous gel-like sealing layer; a waterproof elastic sealing gasket is laid, which is tightly attached to the sealing adhesive.

[0062] Coordinated treatment of retaining structure and interface: The retaining pile surfaces on both sides of the bottom of the entrance and exit are roughened and coated with cement-based penetrating crystalline waterproof coating, with the coating height extending to the long side coverage of the steel plate waterstop; the waterproof coating is seamlessly connected with the waterstop adhesive and sealing gasket to form a side sealing barrier.

[0063] Cast-in-place section pouring and curing: The bottom of the entrance and exit section is poured in layers using micro-expansion concrete. During pouring, avoid the vibrator hitting the grouting pipe, waterstop and waterproof membrane. Focus on vibrating the area around the steel plate waterstop to ensure that the concrete is tightly wrapped with the waterstop and waterproof membrane. After pouring, keep it moist and cure until the design strength.

[0064] Grouting: After the concrete has cured, waterproof grout is injected through the grouting pipe to fill the potential gaps between the waterproof membrane and the concrete, and between the waterstop and the end face, thus completing the closed loop of the bottom seepage prevention system.

[0065] Service life prediction: The structural design and construction meet the relevant specifications and requirements. The waterproofing system adopts the comprehensive protection principle of "prevention first, combined with drainage". During the operation period, convenient post-repair can be achieved through pre-installed grouting pipes. It works in conjunction with the main structure of the subway and provides mutual protection. It is expected that its service life will meet the design service life of 100 years of the main structure.

[0066] Improved construction efficiency and reduced maintenance costs: This structure incorporates pre-installed grouting pipes within the waterproofing system, forming a "protection-remediation" linkage with the galvanized steel plate waterstop. The rigid support of the steel plate waterstop helps position components such as the grouting pipes and waterstop sealant, preventing displacement and damage of auxiliary components during construction, reducing construction difficulty, and improving construction efficiency and quality stability. If minor leaks occur later, there is no need to damage the structure; simply injecting waterproof grout through the grouting pipes can fill the gaps. Combined with the long-lasting protection of the steel plate waterstop, compared to the need to chisel open the surface of the structure for positioning and repair after leakage, the repair cost is lower and the efficiency is higher, overcoming the problems of difficult and costly repair of general waterproofing components.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A three-dimensional continuous waterproof structure suitable for prefabricated subway stations, characterized in that: A three-dimensional continuous waterproof structure is set at the connection end face between the prefabricated section and the cast-in-place section of the prefabricated subway station, and is arranged in a whole ring along the connection end face to form a composite waterproof system; The composite waterproofing system includes an L-shaped rigid plate composite waterstop, a grouting pipe, a waterstop adhesive, and a sealing gasket, arranged sequentially from the water-facing side to the water-repellent side. The short side of the L-shaped rigid plate composite waterstop is welded to the surface of the precast steel plate embedded in the precast section through impermeable welding, and is tightly fitted with the end face of the precast section without gaps to block the seepage path on the water-facing side. The long side of the L-shaped rigid plate composite waterstop extends into the interior of the cast-in-place section, is tied and fixed with the reinforcing steel of the cast-in-place section, and is then wrapped by the cast-in-place concrete to form a physical seepage barrier. At the same time, it works in conjunction with the elastic sealing of the waterstop adhesive and the active leak repair of the grouting pipe to form a dual seepage-proof structure that combines active blocking with passive remediation.

2. The three-dimensional continuous waterproof structure adapted to prefabricated subway stations according to claim 1, characterized in that: The L-shaped rigid plate composite waterstop has a width of 240mm, a thickness of 3mm, a short side length of 40mm, and a long side length of 200mm. The joints of the L-shaped rigid plate composite waterstop are fully welded, and the outside of the weld is wrapped with water-swellable rubber tape. The rigid plate in the L-shaped rigid plate composite waterstop is a galvanized steel plate. L-shaped rigid plate composite waterstop is adapted to the corner of precast components through bending treatment to tolerate a flatness deviation of 3mm-5mm on the end face of the precast section.

3. The three-dimensional continuous waterproof structure adapted to prefabricated subway stations according to claim 1, characterized in that: The tension holes on both sides of the precast section are sealed with micro-expansion concrete, the threaded steel is sealed with water-swellable rubber, the anchor head is sealed with water-swellable rubber, and the short side of the pre-embedded steel plate and L-shaped rigid plate composite waterstop on the end face of the precast section is welded with impermeable weld. Water-swellable rubber rings are fitted at the anchorage of the precast steel bars, and the coverage of the water-swellable rubber rings overlaps with that of the L-shaped rigid plate composite waterstop. Water-swellable rubber blocks are laid on the outside of the anchor head at the anchorage of the steel bars and covered with stainless steel cover plates. The gaps at the edges of the stainless steel cover plates are filled with sealant, and the edges of the stainless steel cover plates wrap around the long side of the L-shaped rigid plate composite waterstop.

4. The three-dimensional continuous waterproof structure adapted to prefabricated subway stations according to claim 1, characterized in that: Grouting pipes are laid out in a ring along the connection end face for later injection of waterproof grout to fill potential gaps.

5. The three-dimensional continuous waterproof structure adapted to prefabricated subway stations according to claim 1, characterized in that: The short side of the L-shaped rigid plate composite waterstop is welded to the embedded steel plate through impermeable welding. The embedded steel plate is a galvanized steel plate with a width of 50mm and a thickness of 3mm.

6. The three-dimensional continuous waterproof structure adapted to prefabricated subway stations according to claim 1, characterized in that: The precast section uses the same grade of micro-expansion concrete as the cast-in-place section, so that after pouring, it can be tightly wrapped with the long side of the L-shaped rigid plate composite waterstop to form a rigid bond.

7. The three-dimensional continuous waterproof structure adapted to prefabricated subway stations according to claim 1, characterized in that: Water-stop adhesive is continuously laid on the connection end face of the precast section and the cast-in-place section to form a continuous ring of gel-like sealing layer. A sealing gasket is laid on the back side of the gel-like sealing layer to fill the gap.

8. The construction method for a three-dimensional continuous waterproof structure adapted to prefabricated subway stations as described in any one of claims 1-7, characterized in that: Includes the following steps: S1. Pre-treatment of the end face of the prefabricated section; S11. Remove laitance, rust, debris and oil stains from the connection end face between the precast section and the cast-in-place section to ensure that there are no contaminants attached to the connection end face; S12. Check the flatness of the precast section end face, grind the protruding parts, and control the flatness deviation of the end face within the range of 3mm-5mm to meet the bonding requirements of the L-shaped rigid plate composite waterstop. S13. Clean the residual debris inside the tensioning holes on both sides of the precast section to ensure that the inner wall of the hole is dry in preparation for subsequent sealing. S2 and L-shaped rigid plate composite waterstop strip installation and fixing; S21. Based on the dimensions of the corner of the precast component, the L-shaped rigid plate composite waterstop is bent to fit the corner curvature. S22. The short side of the L-shaped rigid plate composite waterstop is attached to the embedded steel plate on the end face of the precast section after treatment. The short side is fixed to the surface of the embedded steel plate of the precast section by waterproof welding to ensure that the short side is tightly attached to the end face of the precast section without gaps. S23. Tie the long side of the L-shaped rigid plate composite waterstop to the pre-set steel bars of the cast-in-place section to prevent the waterstop from shifting during concrete pouring. S24. Full welding is performed on the joints of the L-shaped rigid plate composite waterstop arranged in a ring. After the weld is completed, water-swellable rubber tape is wrapped around the outside to ensure that the joint is sealed without any leakage or breakpoints. S3. Layout of waterproof auxiliary components; S31 is laid out in a ring along the end face connecting the precast section and the cast-in-place section. It is fixed with L-shaped rigid plate composite waterstop by tie straps or brackets to avoid displacement and blockage during pouring. S32. Apply waterproof adhesive evenly to the entire ring of the connecting end face to form a continuous adhesive sealing layer. S33 lays a sealing gasket in a full ring on the back side of the water-stop adhesive to ensure that the sealing gasket is tightly attached to the water-stop adhesive without wrinkles or gaps, thus achieving flexible sealing and supplementation. S4. Cast-in-place section with micro-expansion concrete pouring; S41. Prepare micro-expansion concrete that is compatible with the strength grade of precast concrete components, and control the concrete mix proportion to meet the shrinkage requirements. S42. Micro-expansion concrete is poured into the cast-in-place section in layers. During the pouring process, the area around the L-shaped rigid plate composite waterstop is vibrated to ensure that the micro-expansion concrete tightly wraps the long side of the L-shaped rigid plate composite waterstop without air bubbles or gaps, forming a rigid bond. S5. Curing of cast-in-place concrete: After the cast-in-place concrete is poured, cover and keep it moist for curing, and continue curing until the concrete reaches the design strength grade. S6. Grouting pipe repair; S61. After the concrete curing is completed, check the unobstructedness of each grouting pipe, remove any blocked grouting pipes and replace or unclog them. S62. Prepare a waterproof grout suitable for micro-expansion concrete used for sealing tension holes; S63. Inject waterproof grout into the connection between the precast section and the cast-in-place section through the grouting pipe. When there is uniform grout overflow at the outlet end of the grouting pipe and the pressure is stable, stop grouting through the grouting pipe. Complete the grouting operation of all grouting pipes in the whole ring in sequence to form an active seepage prevention and replenishment.

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