FRP (Fiber Reinforce Plastic) grid cement paste composite lining for shield tunnel

Abstract

The utility model discloses an FRP gridding cement paste composite lining for a shield tunnel, which comprises an FRP inner pipe and a cement paste outer pipe arranged on the outer side of the FRP inner pipe, an FRP gridding layer integrally wound with the FRP inner pipe is arranged on the outer peripheral surface of the FRP inner pipe, the inner wall of the cement paste outer pipe is attached to the outer wall of the FRP inner pipe, and the FRP gridding layer is arranged on the outer peripheral surface of the FRP inner pipe. And the FRP grid layer is embedded in the cement paste outer pipe. The FRP inner pipe and the cement paste outer pipe are combined, and the FRP grid layer which is integrally formed in a winding mode is arranged on the periphery of the FRP inner pipe, so that the FRP grid layer is embedded into the cement paste outer pipe, and the bonding strength between the FRP inner pipe and the cement paste outer pipe is remarkably improved. By means of the structure, the overall compression resistance of the lining is enhanced, the thickness of the FRP inner pipe is reduced, the material cost is reduced, meanwhile, the durability and corrosion resistance of the lining are improved, and the lining is particularly suitable for shield tunnels in the marine environment.

Description

Technical Field

[0001] This utility model relates to the field of composite material applications, and in particular to an FRP grid cement grout composite lining for shield tunnels. Background Technology

[0002] As a crucial component of modern urban underground transportation, water conservancy projects, and cross-sea passage construction, the performance of the lining structure of shield tunnels directly affects the safety and service life of the tunnels. Traditional shield tunnel lining materials mainly use reinforced concrete structures, which, although possessing high compressive strength and a certain degree of durability, exhibit significant shortcomings in performance under complex geological conditions and harsh environments (such as high humidity, high salinity, and highly corrosive media).

[0003] First, when reinforced concrete structures are exposed to corrosive environments for extended periods, the reinforcing steel is prone to corrosion, leading to concrete cracking and spalling, which in turn weakens the overall load-bearing capacity of the lining. This is especially true in marine environments or areas with high groundwater levels, where salt and moisture erosion accelerates steel corrosion, increasing maintenance costs and shortening the tunnel's lifespan. Second, traditional lining materials are prone to deformation and cracking under complex geological conditions (such as soft soil, faults, and high water pressure), affecting the tunnel's stability and safety. Furthermore, the significant weight of reinforced concrete structures increases construction difficulty and transportation costs, a problem particularly pronounced in long-distance tunnel projects.

[0004] In recent years, fiber-reinforced polymer (FRP) composites have gradually become a research hotspot in tunnel lining materials due to their excellent properties such as high strength, lightweight, and corrosion resistance. However, existing FRP lining structures mostly use single materials or simple composite forms, making it difficult to simultaneously meet the multiple performance requirements of high strength, corrosion resistance, and impact resistance. Therefore, developing a shield tunnel lining structure that combines high strength, durability, and ease of construction has become a pressing technical challenge in the current engineering field. Utility Model Content

[0005] To address the aforementioned problems, this utility model provides an FRP grid cement grout composite lining for shield tunnels.

[0006] This utility model provides an FRP grid cement grout composite lining for shield tunnels and its preparation method, adopting the following technical solution:

[0007] An FRP grid cement grout composite lining for shield tunnels includes an FRP inner tube and a cement grout outer tube disposed outside the FRP inner tube. An FRP grid layer integrally wound with the FRP inner tube is disposed on the outer circumferential surface of the FRP inner tube. The inner wall of the cement grout outer tube is attached to the outer wall of the FRP inner tube, and the FRP grid layer is embedded in the cement grout outer tube.

[0008] The above technical solution combines the FRP inner tube with the cement grout outer tube, and incorporates an integrally wound FRP mesh layer around the outer periphery of the FRP inner tube. This allows the FRP mesh layer to embed within the cement grout outer tube, significantly improving the bond strength between the two. This structure not only enhances the overall compressive strength of the lining but also reduces the thickness of the FRP inner tube, lowering material costs. Simultaneously, it improves the lining's durability and corrosion resistance, making it particularly suitable for shield tunnels in marine environments.

[0009] As a preferred embodiment of this utility model, the FRP inner tube is composed of multiple segments spliced ​​together in the axial direction, and a spigot and a socket are respectively provided at the connection of two adjacent FRP inner tube segments, and the spigot can be inserted into the socket.

[0010] The above technical solution employs a multi-segment splicing structure in the axial direction of the FRP inner tube, and sets spigots and sockets at the joints of adjacent FRP inner tube segments, ensuring a tight connection and good sealing between the FRP inner tube segments. This design not only simplifies the construction process but also improves the overall stability and impermeability of the lining.

[0011] As a preferred embodiment of this utility model, a connecting protrusion formed by winding is provided on the outer circumferential surface of the connection between two adjacent FRP inner tubes, and a fixing hole is provided on the connecting protrusion. The two adjacent FRP inner tubes are also locked by installing locking bolts on the fixing holes.

[0012] By employing the aforementioned technical solution, a spirally wound connecting ring is installed at the joint of two adjacent FRP inner tube sections, and a locking bolt is installed through the fixing hole, further enhancing the structural strength of the joint. This design not only improves the tensile strength of the lining but also ensures the stability of the joint, preventing loosening due to external pressure or vibration, and extending the service life of the lining.

[0013] As a preferred embodiment of this invention, the locking bolt is a double-ended bolt.

[0014] The above technical solution, which uses a double-headed bolt design, allows more of the bolt to be embedded inside the cement grout outer pipe, thereby significantly improving the bonding strength between the cement grout outer pipe and the FRP inner pipe.

[0015] As a preferred embodiment of this utility model, a plurality of FRP protruding rings are further provided on the outer periphery of the FRP inner tube, each FRP protruding ring being distributed along the axial direction of the FRP inner tube, and a connecting rib is embedded in the FRP protruding ring, with both ends of the connecting rib extending out of the FRP protruding ring.

[0016] The above technical solution involves setting multiple FRP protruding rings on the outer periphery of the FRP inner tube, with connecting ribs embedded within these rings. The ends of these connecting ribs extend beyond the protruding rings and embed into the cement grout outer tube, further enhancing the bonding force between the FRP inner tube and the cement grout outer tube. This not only improves the overall shear resistance of the lining but also ensures its stability under complex stress conditions, extending its service life.

[0017] As a preferred embodiment of the present invention, the connecting rib includes a fixing part embedded in the FRP convex ring and a connecting part extending out of the FRP convex ring, wherein the connecting part extends in a direction away from the center of the FRP convex ring.

[0018] Through the above technical solution, the fixing part of the connecting bar is embedded in the FRP convex ring, and the connecting part extends away from the center of the convex ring and is embedded in the cement grout outer pipe, making the bond between the FRP inner pipe and the cement grout outer pipe tighter. This not only improves the tensile and shear strength of the lining, but also ensures the structural stability of the lining during long-term use, making it particularly suitable for shield tunnel projects that require high strength and durability.

[0019] In summary, this utility model has at least one of the following beneficial technical effects:

[0020] 1. This utility model combines an FRP inner tube with a cement slurry outer tube, and sets an integrally wound FRP mesh layer around the outer periphery of the FRP inner tube, allowing the FRP mesh layer to embed inside the cement slurry outer tube, significantly improving the bonding strength between the FRP inner tube and the cement slurry outer tube. This structure not only enhances the overall compressive and shear strength of the lining, but also reduces the thickness of the FRP inner tube, lowering material costs, while simultaneously improving the durability and corrosion resistance of the lining.

[0021] 2. This utility model features a spirally wound connecting ring at the joint of two adjacent FRP inner tube sections, and a double-ended bolt is installed through a fixing hole, further enhancing the structural strength of the joint. The double-ended bolt design allows more of the bolt to be embedded inside the cement grout outer tube, significantly improving the bonding strength between the cement grout outer tube and the FRP inner tube. This not only improves the tensile strength of the lining but also ensures the stability of the joint, preventing loosening due to external pressure or vibration and extending the service life of the lining.

[0022] 3. Multiple FRP raised rings are installed around the outer circumference of the FRP inner tube, with connecting ribs embedded within these rings. The ends of these connecting ribs extend beyond the raised rings and embed into the cement grout outer tube, further enhancing the bond between the FRP inner tube and the cement grout outer tube. This design not only improves the overall shear resistance of the lining but also ensures its stability under complex stress conditions, extending its service life. Through the cooperation of the FRP raised rings and connecting ribs, the lining can maintain higher structural integrity when subjected to external pressure or vibration. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the FRP grid cement grout composite lining structure for shield tunnels according to Embodiment 1 of this utility model.

[0024] Figure 2 yes Figure 1 Enlarged view of part A.

[0025] Figure 3 This is a schematic diagram of the FRP grid cement grout composite lining structure for shield tunnels according to Embodiment 2 of this utility model.

[0026] Figure 4 yes Figure 3 Enlarged view of part B.

[0027] Figure 5 This is a schematic diagram of the FRP grid cement grout composite lining structure for shield tunnels according to Embodiment 3 of this utility model.

[0028] Figure 6 yes Figure 5 Enlarged view of part C.

[0029] Explanation of reference numerals in the attached drawings: 1. FRP inner tube; 2. FRP mesh layer; 3. Cement grout outer tube; 4. Socket; 5. Spiral; 6. First connecting protrusion ring; 7. Second connecting protrusion ring; 8. Connecting bolt; 9. FRP protrusion ring; 10. Connecting rib. Detailed Implementation

[0030] The following is in conjunction with the appendix Figure 1-6 The present invention will be described in further detail below.

[0031] Example 1:

[0032] Reference Figures 1 to 2 This embodiment discloses an FRP grid cement grout composite lining for shield tunnels, including an FRP inner tube 1 and a cement grout outer tube 3 disposed outside the FRP inner tube 1. The FRP material has a low flow resistance coefficient, resulting in low energy consumption for subsequent water transport and making it less prone to marine organism adhesion. An FRP grid layer 2, integrally wound with the FRP inner tube 1, is disposed on the outer circumferential surface of the FRP inner tube 1. In this embodiment, the FRP grid layer 2 is formed by winding the FRP inner tube 1 into a grid structure on its outer wall after the inner tube 1 has been wound. The included angle of the grid is acute, making the preparation of the FRP grid layer 2 simple and highly mechanized.

[0033] The inner wall of the cement grout outer tube 3 is fitted to the outer wall of the FRP inner tube 1, and the FRP mesh layer 2 is embedded within the cement grout outer tube 3. The FRP mesh layer 2 ensures a tight bond between the FRP inner tube 1 and the cement grout outer tube 3, improving the adhesion strength between them. The cement grout outer tube 3 enhances the overall strength of the lining, thereby reducing the thickness of the FRP inner tube 1 and lowering the overall material cost. Depending on the actual strength requirements, the cement grout outer tube 3 may or may not include a reinforcing mesh cage.

[0034] The FRP inner tube 1 is composed of multiple segments spliced ​​together in the axial direction. At the connection between two adjacent FRP inner tube segments 1, a spigot 5 and a socket 4 are respectively provided. The spigot 5 can be inserted into the socket 4, thus ensuring that the two adjacent FRP inner tube segments 1 are tightly connected and have good sealing performance. If necessary, an O-ring can be set between the spigot 5 and the socket 4 to further improve the overall sealing performance.

[0035] Example 2:

[0036] Reference Figure 3 and Figure 4 In this embodiment, all other aspects are the same as in embodiment 1. The difference is that, in order to improve the strength of the connection between two adjacent FRP inner tubes 1, a spirally wound connecting protrusion is provided on the outer circumferential surface of the connection between the two adjacent FRP inner tubes 1, namely a first connecting protrusion 6 and a second connecting protrusion 7. Fixing holes are provided on both the first connecting protrusion 6 and the second connecting protrusion 7. The two adjacent FRP inner tubes 1 are also locked by installing locking bolts on the fixing holes. In this embodiment, the locking bolt is a double-ended bolt, and the double-ended bolt is relatively long, with a large part of it extending out of the fixing block.

[0037] By setting a first connecting protrusion 6 and a second connecting protrusion 7 at the connection between two adjacent FRP inner tubes 1, the strength of the connection is not only improved, but also the connection between the two adjacent FRP inner tubes 1 is more stable and less likely to fall off. In addition, the double-ended bolts extending out of the fixing holes can be embedded into the cement grout outer tube 3, making the FRP inner tube 1 and the cement grout outer tube 3 more tightly and reliably connected.

[0038] Example 3:

[0039] Reference Figure 5 and Figure 6In this embodiment, everything else is the same as in embodiment 2, except that: in this embodiment, multiple FRP protruding rings 9 are provided on the outer periphery of the FRP inner tube 1, and each FRP protruding ring 9 is distributed along the axial direction of the FRP inner tube 1. A connecting rib 10 is embedded in the FRP protruding ring, and both ends of the connecting rib 10 extend out of the FRP protruding ring 9. In this embodiment, the FRP protruding ring 9 is formed by winding it around the outer wall of the FRP inner tube 1. During the winding process, the connecting rib 10 is inserted, and continued winding allows the connecting rib 10 to be embedded in the FRP protruding ring 9, ensuring a tight connection between the connecting rib 10 and the FRP protruding ring 9, preventing the connecting rib 10 from falling out of the FRP protruding ring 9.

[0040] The connecting rib 10 includes a fixing part embedded in the FRP protruding ring 9 and a connecting part extending out of the FRP protruding ring 9. The connecting part extends away from the center of the FRP protruding ring 9. The connecting part of the connecting rib 10 can be embedded in the cement grout outer pipe 3, thereby making the FRP inner pipe 1 and the cement grout outer pipe 3 more tightly and reliably connected.

[0041] The above are all preferred embodiments of this utility model, and are not intended to limit the scope of protection of this utility model. Therefore, all equivalent changes made to the structure, shape and principle of this utility model should be covered within the scope of protection of this utility model.

Claims

1. A FRP mesh cement mortar composite lining for shield tunneling, characterized by: The FRP inner tube and the cement mortar outer tube are arranged outside the FRP inner tube, a FRP grid layer is integrally wound and formed on the outer circumferential surface of the FRP inner tube, the inner wall of the cement mortar outer tube is attached to the outer wall of the FRP inner tube, and the FRP grid layer is embedded in the cement mortar outer tube.

2. The FRP grid cement mortar composite lining for shield tunneling according to claim 1, characterized in that: The FRP inner tube is spliced in multiple sections in the axial direction, and a spigot and a socket are arranged at the connecting position of the two adjacent FRP inner tubes respectively, and the spigot can be inserted into the socket.

3. The FRP grid cement mortar composite lining for tunneling shield according to claim 2, characterized in that: A connecting convex ring is further arranged on the outer circumferential surface of the connecting position of the two adjacent FRP inner tubes, and a fixing hole is arranged on the connecting convex ring, and the two adjacent FRP inner tubes are further locked by installing a locking bolt on the fixing hole.

4. The FRP grid cement mortar composite lining for tunneling shield according to claim 3, characterized in that: The locking bolt is a double-headed bolt.

5. The FRP grid cement mortar composite lining for tunneling shield according to claim 1, characterized in that: A plurality of FRP convex rings are further arranged on the outer circumferential surface of the FRP inner tube, each FRP convex ring is distributed along the axial direction of the FRP inner tube, a connecting rib is embedded in the FRP convex ring, and both ends of the connecting rib extend out of the FRP convex ring.

6. The FRP grid cement mortar composite lining for tunneling shield according to claim 5, characterized in that: The connecting rib comprises a fixing part embedded in the FRP convex ring and a connecting part extending out of the FRP convex ring, and the connecting part is arranged to extend away from the center of the FRP convex ring.

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