Carbonized prefabricated component and multi-layered tunnel lining anti-seepage structure

Abstract

The utility model discloses a carbonization prefabricated component and tunnel lining multilayer seepage prevention structure, including concrete main part, at least one end of concrete main part is equipped with concave and convex tooth groove structure, and the concave and convex tooth groove structure of adjacent concrete main part is set up adaptively, still be equipped with on concrete main part: hoisting element, connecting element, reinforcing element and positioning element etc., and lining multilayer seepage prevention structure includes the mat layer, bottom plate, midwall, side wall and top plate and its protective layer that set gradually from top to bottom. This carbonization prefabricated component simple structure, easy production and on -the -spot installation, through concave and convex tooth groove structure and connecting element and reinforcing element etc. Setting can promote the connection strength of whole and the seepage prevention performance of joint, and can adopt high accuracy steel mould and the maintenance production mode of standardization, be favorable to the further improvement of structural strength, seepage prevention, durability.

Description

Technical Field

[0001] This utility model relates to the field of building materials and tunnel waterproofing construction technology, specifically to a carbonized precast component and a multi-layer seepage prevention structure for tunnel lining. Background Technology

[0002] In urban tunnel construction, methods such as cut-and-cover and top-and-bottom methods are commonly used. Cut-and-cover methods, in particular, are widely used in shallow-buried or large-scale underground engineering projects due to their advantages of construction safety, ease of dewatering and drainage, and relatively simple equipment. However, tunnel lining structures constructed using the cut-and-cover method often involve the pouring and curing of large volumes of concrete. The stringent curing and quality requirements limit the progress of on-site operations, and the curing site is affected by temperature and weather, leading to long-term disruptions to surrounding traffic and the environment. Furthermore, if the quality of the large-volume concrete pouring is not well controlled, minor defects may develop into seepage channels due to long-term erosion by groundwater and the environment, resulting in leakage. Precast monolithic structures, based on prefabricated components, offer advantages such as shorter construction periods, easier quality control of prefabricated components, and high efficiency through large-scale production. After installation, precast monolithic structures directly bear the surrounding loads and possess strength and impermeability comparable to cast-in-place concrete structures. To further improve structural strength and seepage prevention performance, achieve efficient completion of open-cut tunnel construction, and minimize carbon emissions, this application provides a multi-layer seepage prevention structure based on carbonized precast components. Summary of the Invention

[0003] The purpose of this utility model is to address the problems existing in the prior art by providing a carbonized precast component and a multi-layer seepage prevention structure for tunnel lining.

[0004] To achieve the above objectives, the technical solution adopted by this utility model is as follows: A carbonized precast component includes a concrete body, at least one end of which is provided with a toothed or grooved structure, and adjacent toothed or grooved structures of the concrete body are adapted to each other; the concrete body is further provided with: Lifting components are used to lift the concrete structure. A connecting element is disposed in the concrete body at the grooved structure and is used to connect adjacent concrete bodies; Reinforcing elements are disposed between adjacent groove structures to increase the impermeability of the joints between adjacent concrete bodies. A positioning element is disposed at the mating surface outside the groove structure, and is used for positioning control of the concrete body of other adjacent surfaces that are not connected to the groove structure.

[0005] This carbonized precast component has a simple structure, is easy to manufacture and install on site. The concave-convex groove structure, as well as the setting of the connecting elements and the reinforcing elements, can improve the overall connection strength and the seepage prevention performance at the joints. Moreover, it can use high-precision steel molds and standardized curing and production methods, which is beneficial to further improving the structural strength, seepage prevention and durability.

[0006] Furthermore, the concrete main body is a carbonized impermeable concrete structural component.

[0007] Furthermore, the lifting element is a load-bearing component pre-installed inside and on the surface of the concrete main body according to the size and weight of the carbonized precast component and the on-site lifting requirements.

[0008] Furthermore, the connecting element includes reinforcing bars connecting adjacent concrete bodies and pre-embedded grouting sleeves. For horizontally butt-jointed concrete bodies, a steel plate waterstop is also connected, with folded edges at both ends facing the water-facing side.

[0009] Furthermore, the reinforcing element includes a waterproof rubber gasket and a water-swellable rubber waterstop. For horizontal and corner joints of the concrete body, the water-swellable rubber waterstop is arranged along the length of the groove of the toothed structure; for vertical joints of the concrete body, the waterproof rubber gasket is arranged along the bottom of the groove of the toothed structure.

[0010] Furthermore, the positioning element includes a pre-embedded positioning pin and a positioning hole disposed on the concrete body. The pre-embedded positioning pin and the positioning hole are adapted to each other, and the pre-embedded positioning pin is offset from the concave-convex groove structure and the arrangement of the connecting element.

[0011] Furthermore, the groove cross-section of the concave-convex toothed structure includes at least a trapezoidal groove cross-section and a rectangular groove cross-section.

[0012] A multi-layer seepage-proof structure for tunnel lining using carbonized precast components, comprising a bottom slab, side walls, middle walls, and a top slab assembled from several of the carbonized precast components. The bottom slab is placed on a cushion layer, and a sodium-based bentonite waterproof blanket is placed between the cushion layer and the bottom slab. The side walls and the middle walls are placed on the bottom slab, and the top slab is placed on the side walls and the middle walls. A self-adhesive polymer-modified bitumen waterproof membrane is also laid on the outer side of the side walls and the top slab. A cast-in-place protective layer is provided above the top slab, and an additional asphalt felt isolation layer is laid between the top slab and the cast-in-place protective layer.

[0013] Furthermore, the base plate, the side wall, the middle wall, and the top plate are all multi-layered assembly structures. The multi-layered assembly structures are positioned and connected by the positioning element, and the joints of the concave and convex groove structures of adjacent multi-layered assembly structures are staggered.

[0014] Compared with existing technologies, the beneficial effects of this utility model are: 1. The carbonized precast component has a simple structure, is easy to manufacture and install on-site. The concave-convex groove structure, connecting elements, and reinforcing elements enhance the overall connection strength and the impermeability of the joints. Furthermore, the use of high-precision steel molds and standardized curing methods further improves the overall structural strength, impermeability, and durability. 2. The slag powder, fly ash, and phosphogypsum used in the production of the carbonized precast component effectively realize the resource utilization of solid waste. Combined with carbonization curing technology, this reduces the carbon footprint of the lining project and further increases the density of the concrete structure, improving the strength and impermeability of the precast component. 3. Adjacent precast components use grouting sleeves, reinforcing bars, and steel plate waterstops, and are injected with early-strength expanding mortar, effectively ensuring the integrity of the prefabricated lining structure. The strength, stability, and impermeability are guaranteed, and the wet connection method allows for the existence of errors during the assembly process. 4. The use of a toothed groove structure between adjacent precast components, along with the additional water-swellable rubber waterstop strips and impermeable rubber gaskets, combined with the "T-shaped joint" used in the interlayer components, further improves the overall impermeability of the structure. 5. The sodium-based bentonite waterproof blanket used between the bottom slab and the cushion layer of the tunnel lining has self-healing properties, increasing the impermeability of the lining structure. Its good ductility also reduces the requirements for the flatness of the cushion layer to a certain extent, which helps to improve construction efficiency. Attached Figure Description

[0015] Figure 1 This is a geometric schematic diagram of a carbonized precast component according to the present invention; Figure 2 This is a schematic diagram (horizontal) showing the connection method between the carbonized precast component and adjacent components of this utility model. Figure 3 This is a schematic diagram (corner) showing the connection between the carbonized precast component and adjacent components of this utility model. Figure 4 This is a schematic diagram (vertical direction) showing the connection method between the carbonized precast component and adjacent components of this utility model. Figure 5 This is a schematic diagram showing the positioning and connection method between the carbonized precast component and its adjacent components. Figure 6 This is a schematic diagram of the multi-layer seepage prevention structure for tunnel lining of this utility model; In the diagram: 1. Concrete main body; 2. Lifting components; 3. Embedded grouting sleeve; 4. Corrugated toothed structure; 5. Water-swellable rubber waterstop strip; 6. Steel plate waterstop; 7. Impermeable rubber gasket; 8. Positioning components; 9. Subbase; 10. Sodium bentonite waterproof blanket; 11. Base plate; 12. Side walls; 13. Top plate; 14. Middle wall. Detailed Implementation

[0016] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0017] In the description of this utility model, it should be noted that the terms "middle", "upper", "lower", "left", "right", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0018] Example 1: As Figures 1-5 As shown, a carbonized precast component includes a concrete body 1, at least one end of the concrete body 1 is provided with a toothed structure 4, and the toothed structures 4 of adjacent concrete bodies 1 are adapted to each other; the concrete body 1 is also provided with a hoisting element 2 for hoisting the concrete body. A connecting element is disposed in the concrete body 1 at the groove structure 4, for connecting adjacent concrete bodies 1; Reinforcing elements are disposed between adjacent groove structures 4 to increase the impermeability of the joints between adjacent concrete bodies 1. Positioning element 8 is disposed at the mating surface outside the groove structure 4, and is used for positioning control of other adjacent concrete bodies 1 that are not connected to the groove structure.

[0019] This carbonized precast component has a simple structure, is easy to manufacture and install on site. The concave-convex groove structure 4, as well as the connecting elements and reinforcing elements, can improve the overall connection strength and the seepage prevention performance at the joints. Moreover, it can use high-precision steel molds and standardized curing and production methods, which is beneficial to further improving the structural strength, seepage prevention and durability.

[0020] Furthermore, the concrete main body 1 is a carbonized impermeable concrete structural component. The raw materials used include: cement, fly ash, slag powder, phosphogypsum, coarse aggregate crushed stone, fine aggregate river sand, waste rubber granules, modified composite fibers, activators, water-reducing agents, high-efficiency air-entraining agents, expanding agents, etc. Carbonation curing enhances the density of the concrete structure, improving its strength and impermeability. Impermeability is primarily achieved through the self-impermeability of the component structure, while special attention is paid to the joints of the components.

[0021] The concrete body of the carbonized precast component is a cuboid or other polyhedron of a specific shape. Its size and weight meet the requirements of mechanical hoisting. Its size and shape can be appropriately adjusted according to the tunnel structure. The end has a toothed structure that connects with adjacent components.

[0022] After the concrete body 1 is poured, formed and demolded, it is placed in an atmosphere with a temperature of 25℃, a relative humidity of 80% and a CO2 concentration of 20% for 72 hours. Then, carbon dioxide is discharged, water is sprayed to keep it moist, and it is cured under standard curing conditions for 28 days.

[0023] Furthermore, the lifting element 2 is a load-bearing component pre-installed inside and on the surface of the concrete main body 1 according to the size and weight of the carbonized precast component and the on-site lifting requirements.

[0024] Furthermore, the connecting element includes a steel bar connecting adjacent concrete bodies 1 and a pre-embedded grouting sleeve 3. For horizontally butt-jointed concrete bodies 1, a steel plate waterstop 6 is also connected. The two ends of the steel plate waterstop 6 are provided with folded edges facing the water-facing side.

[0025] These connecting elements provide tensile, shear, and seepage-proof properties, enabling the interconnection of adjacent precast components to form a continuous spatial structure. The pre-embedded grouting sleeves 3 allow for the injection of early-strength, micro-expansion mortar into the joints of adjacent concrete bodies 1, enhancing the overall structural integrity and joint seepage prevention. This effectively ensures the integrity, strength, stability, and seepage prevention of the prefabricated lining structure, while the wet connection method allows for errors during assembly.

[0026] In addition to injecting micro-expansion anti-seepage mortar into the gaps, hydrophilic epoxy reinforcing materials and sealants are used to further enhance the impermeability of the joints.

[0027] Furthermore, the reinforcing element includes a waterproof rubber gasket 7 and a water-swellable rubber waterstop strip 5. For the concrete body 1 that is horizontally or at a corner, the water-swellable rubber waterstop strip 5 is arranged along the length of the groove of the toothed structure 4. For the concrete body 1 that is vertically connected, the waterproof rubber gasket 7 is arranged along the bottom of the groove of the toothed structure 4.

[0028] The groove cross-section of the groove structure 4 includes at least a trapezoidal groove cross-section and a rectangular groove cross-section. The horizontal docking can adopt the groove structure with a trapezoidal groove cross-section, and the vertical docking can adopt the groove structure with a rectangular groove cross-section.

[0029] By setting the water-swellable rubber waterstop strip at the trapezoidal groove cross-section and the seepage-proof rubber gasket at the rectangular groove cross-section, the seepage resistance at the joint can be further improved, and the effect is more targeted.

[0030] Furthermore, the positioning element 8 includes a pre-embedded positioning pin and a positioning hole disposed on the concrete body 1. The pre-embedded positioning pin and the positioning hole are adapted to each other, and the pre-embedded positioning pin is offset from the concave-convex toothed structure and the arrangement of the connecting element.

[0031] The pre-embedded positioning pins and positioning holes facilitate the positioning of the upper and lower concrete main bodies, while the concave and convex groove structure of the concrete main body also helps with positioning control during the assembly process.

[0032] Example 2: This example provides a multi-layer seepage-proof tunnel lining structure using the carbonized precast components from Example 1, combined with... Figure 6 As shown, the multi-layered seepage-proof tunnel lining structure includes a bottom slab 11, side walls 12, middle walls 14, and a top slab 13 assembled from several carbonized precast components. The bottom slab 11 is placed on a cushion layer 9, and a sodium-based bentonite waterproof blanket 10 is placed between the cushion layer 9 and the bottom slab 11. The side walls 12 and the middle walls 14 are placed on the bottom slab 11, and the top slab 13 is placed on the side walls 12 and the middle walls 14. Self-adhesive polymer-modified bitumen waterproof membrane is also laid on the outer side of the side walls 12 and the top slab 13. A cast-in-place protective layer is provided above the top slab 13, and an additional asphalt felt isolation layer is laid between the top slab and the cast-in-place protective layer.

[0033] In this multi-layered seepage-proof tunnel lining structure based on carbonized precast components, in addition to the strong seepage-proof performance of the bottom slab 11, side walls 12, middle walls 14 and top slab 13 made of the carbonized precast components, a layer of sodium-based bentonite waterproof blanket 10 is used between the bottom slab 11 and the cushion layer 9, and a self-adhesive polymer-modified bitumen waterproof membrane is used on the outside of the side walls 12 and the top slab 13, which can further enhance the overall seepage-proof performance of the structure.

[0034] The sodium-based bentonite waterproof blanket 10 used has self-healing properties that increase the impermeability of the lining structure, and its good ductility reduces the requirements for the flatness of the subbase to a certain extent, which helps to improve construction efficiency.

[0035] Furthermore, the base slab 11, the side walls 12, the middle walls 14, and the top slab 13 are all multi-layered prefabricated structures. These multi-layered prefabricated structures are connected and positioned by the positioning elements 8, and the joints of the concave-convex groove structures 4 of adjacent multi-layered prefabricated structures are staggered. That is, for the base slab structure formed by stacking the required multi-layered prefabricated components, the upper and lower adjacent prefabricated components are assembled in a staggered manner, and the joints of the upper and lower layers form a "T-shaped joint". This method can further improve the impermeability of the joints.

[0036] Example 3: This example provides a production and assembly method for the multi-layer seepage-proof tunnel lining structure based on carbonized precast components described in Example 2, specifically including the following steps: Step 1: Design the cross-sectional form of the main concrete structure according to the site conditions, and design the component size and layout according to the stress analysis and hoisting conditions, and design the reinforcement configuration and embedded part setting scheme.

[0037] Step 2, Preparation and coordination of raw materials for carbonized precast components: The raw materials used in the concrete of the carbonized precast components are P•O42.5 cement, slag powder, fly ash, coarse aggregate, fine aggregate, fiber, water-reducing agent, air-entraining agent, and expanding agent. The slag powder used is S95 grade granulated blast furnace slag, and the fly ash used is Grade I fly ash, conforming to the standards GB / T 1596-2017 "Fly Ash for Cement and Concrete" and GB / T18046-2017 "Granulated Blast Furnace Slag Powder for Cement, Mortar and Concrete". The slag powder, fly ash, phosphogypsum, and cement are sieved through a 200-mesh sieve. The coarse aggregate used is sieved into a continuous particle size of 5-25 mm according to GB / T14685-2022. The fiber used is basalt fiber with a diameter of 17 μm and lengths of 6 mm, 9 mm, 12 mm, and 18 mm, mixed in equal mass quantities. The fine aggregate used is natural river sand with a fineness modulus of 2.50; the water-reducing agent used is polycarboxylate-based high-efficiency water-reducing agent PCE; the air-entraining agent used is dodecyl dimethylamine oxide (OA-12); and the expanding agent used is magnesium oxide expanding agent with an activity of 90s. The dosage of the water-reducing agent is 1%, the dosage of the air-entraining agent is 0.01%, and the dosage of the magnesium oxide expanding agent is 4%.

[0038] The cement, fly ash, slag powder, and phosphogypsum are mixed evenly in a mass ratio of 8:1:1:0.5 to form a mixed cementitious material. The proportions of each material are shown in the table below.

[0039] After thoroughly mixing the required coarse aggregate, fine aggregate, and fiber, add 50% of the mixing water and stir thoroughly to pre-wet the mixture. Then add the mixed cementitious material and stir thoroughly for 60 seconds. Finally, add the remaining water, water-reducing agent, air-entraining agent, and foam solution to the mixing system and stir thoroughly.

[0040] Step 3: Casting and curing of carbonized precast components: The precast component template is made of high-strength steel and pre-integrates embedded positioning threaded holes and positioning rods. The steel mold, reinforcing steel frame, and embedded parts are cleaned, and a release agent is applied. First, the bottom mold is fixed; the side molds are all set on the bottom mold and secured with bolts and positioning pins. Reinforcing steel is tied, and functional components (connecting elements, positioning elements, etc.) are embedded, with anti-clogging measures taken for the embedded components. The mixed grout is poured into the mold, avoiding easily clogged components. Mechanical vibration is used for molding, vibrating while pouring, avoiding the precast components and reinforcing steel frame, ensuring there are no large air pockets inside the grout or between the grout and the template. After pouring, it is cured under standard conditions for 48 hours before demolding. The curing environment is then adjusted to an atmosphere of 25℃, 80% relative humidity, and 20% carbon dioxide concentration for 72 hours, followed by another 28 days of curing in a standard curing environment. The grooves for the pre-reserved rubber waterstop strips are cleaned, and the rubber waterstop strips are adhered to the grooves using high-strength rubber adhesive.

[0041] Step 4: Construction of the outer seepage prevention structure of the lining structure: After leveling the support sidewalls and pouring and curing the base slab, lay a layer of sodium bentonite waterproofing mat on top of the base slab. The overlap width at the joints of adjacent waterproofing mats must be at least 100mm, and bentonite granules should be sprinkled at the overlaps. Rubber waterstops and sealant should be used to seal the pipe penetrations. A self-adhesive polymer-modified bitumen waterproofing membrane is laid on the outer side of the sidewalls. An additional 3mm thick single-sided self-adhesive polymer-modified bitumen waterproofing membrane is laid within 500mm of the corners. The joints of adjacent membranes are mechanically fixed. An additional layer of asphalt felt is laid as an isolation layer between the top slab and the outside of the waterproofing membrane.

[0042] Step 5, Assembly of carbonized precast component lining: Based on the pre-designed assembly positions and forms of the precast components, the precast components are assembled from bottom to top in the order of bottom slab-side wall-middle wall-top slab. Precast components between adjacent layers are positioned and locked using positioning pins, and are connected to each other using tongue-and-groove joints, reinforcing bars, and grouting sleeves. After each layer of components is connected, early-strength, micro-expansion mortar is injected into it through the grouting sleeves. After the grout has set, hydrophilic epoxy reinforcing material and sealant are used to further enhance the impermeability of the joints.

[0043] This method replaces a portion of cement with industrial solid waste and introduces basalt-polypropylene composite fiber reinforced concrete precast components to enhance crack resistance, seepage prevention, and durability. During the precast component preparation process, carbonation curing is employed to improve the structural density, strength, and seepage prevention of the precast components. This achieves the resource utilization of solid waste and the stable mineral sequestration of carbon dioxide by the tunnel lining material. Using precast components as secondary tunnel lining material offers advantages in construction convenience, and standardized production and curing processes contribute to improved structural construction quality. The method utilizes assembly and combination construction. Compared to cast-in-place concrete, precast lining blocks are easier to pour and facilitate temperature control. Multi-layered seepage prevention in the lining relies primarily on structural self-waterproofing, while also emphasizing multi-layered waterproofing structures at component joints, ensuring the reliability of the lining's seepage prevention.

[0044] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A carbonized precast component, comprising a concrete body, characterized in that, At least one end of the concrete body is provided with a toothed structure, and the toothed structures of adjacent concrete bodies are adapted to each other; the concrete body is also provided with: Lifting components are used to lift the concrete structure. A connecting element is disposed in the concrete body at the grooved structure and is used to connect adjacent concrete bodies; Reinforcing elements are disposed between adjacent groove structures to increase the impermeability of the joints between adjacent concrete bodies. A positioning element is disposed at the mating surface outside the groove structure, and is used for positioning control of the concrete body of other adjacent surfaces that are not connected to the groove structure.

2. The carbonized precast component according to claim 1, characterized in that, The concrete main body is a carbonized impermeable concrete structural component.

3. The carbonized precast component according to claim 1, characterized in that, The lifting element is a load-bearing component pre-installed inside and on the surface of the concrete main body according to the size and weight of the carbonized precast component and the on-site lifting requirements.

4. The carbonized precast component according to claim 1, characterized in that, The connecting element includes reinforcing bars connecting adjacent concrete bodies and pre-embedded grouting sleeves. For horizontally butt-jointed concrete bodies, a steel plate waterstop is also connected. The two ends of the steel plate waterstop are folded and face the water-facing side.

5. The carbonized precast component according to claim 1, characterized in that, The reinforcing element includes a waterproof rubber gasket and a water-swellable rubber waterstop. For horizontal and corner joints of the concrete body, the water-swellable rubber waterstop is arranged along the length of the groove of the toothed structure. For vertical joints of the concrete body, the waterproof rubber gasket is arranged along the bottom of the groove of the toothed structure.

6. The carbonized precast component according to claim 1, characterized in that, The positioning element includes a pre-embedded positioning pin and a positioning hole disposed on the concrete body. The pre-embedded positioning pin and the positioning hole are adapted to each other and the pre-embedded positioning pin is offset from the concave-convex toothed structure and the arrangement of the connecting element.

7. The carbonized precast component according to claim 1, characterized in that, The groove cross-section of the concave-convex toothed structure includes at least a trapezoidal groove cross-section and a rectangular groove cross-section.

8. A multi-layer seepage-proof tunnel lining structure using carbonized precast components as described in any one of claims 1 to 7, characterized in that, The multi-layered seepage-proof tunnel lining structure includes a bottom slab, side walls, middle walls, and a top slab assembled from several carbonized precast components. The bottom slab is placed on a cushion layer, and a sodium-based bentonite waterproof blanket is placed between the cushion layer and the bottom slab. The side walls and the middle walls are placed on the bottom slab, and the top slab is placed on the side walls and the middle walls. A self-adhesive polymer-modified bitumen waterproof membrane is also laid on the outer side of the side walls and the top slab. A cast-in-place protective layer is provided above the top slab, and an additional asphalt felt isolation layer is laid between the top slab and the cast-in-place protective layer.

9. The multi-layer seepage-proof structure for tunnel lining of carbonized precast components according to claim 8, characterized in that, The base plate, the side walls, the middle walls, and the top plate are all multi-layered assembly structures. The multi-layered assembly structures are positioned and connected by the positioning elements, and the joints of the concave and convex groove structures of adjacent multi-layered assembly structures are staggered.

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