A prefabricated lining construction method for large-section tunnels

Abstract

This invention discloses a construction method for prefabricated lining of large-section tunnels, comprising the following steps: S101, prefabricating prefabricated RPC lining segments, each segment including a reinforcing convex edge and a lining arc surface, with a pre-reserved connection and sealing structure, and grouting pre-reserved holes on the lining arc surface; S201, transporting the prefabricated RPC lining segments to the tunnel construction site; S301, assembling the prefabricated RPC lining segments using a trolley device to form a tunnel lining structure; S401, sealing the joints between the prefabricated RPC lining segments in the tunnel lining structure; S501, grouting the back of the tunnel lining structure through the grouting pre-reserved holes. This invention optimizes the design of prefabricated RPC lining segment materials, structure, and supporting construction equipment and processes. Compared with existing lining construction methods, it has advantages in terms of material consumption, construction period, ease of construction, quality, and safety performance, and has significant engineering application value, especially suitable for the application of large-section tunnel lining structures.

Description

Technical Field

[0001] This invention relates to the field of tunnel construction technology, and in particular to a prefabricated lining construction method for large-section tunnels. Background Technology

[0002] As my country's transportation infrastructure extends into the complex mountainous regions of western China, mountain tunnels face challenges such as deep burial, high ground stress, and fractured surrounding rock. Traditional cast-in-place concrete secondary lining suffers from low construction efficiency, difficulty in quality control, and poor working conditions, necessitating technological upgrades. Traditional secondary lining relies on on-site formwork, pouring, and curing, limiting tunneling efficiency; human factors also affect concrete homogeneity and structural density. Prefabricated secondary lining, through a factory prefabrication and on-site assembly industrialized model, offers advantages such as standardized production, rapid construction, and environmental friendliness, representing a crucial direction for the industrial transformation of tunnel engineering. As tunnel engineering in transportation, water conservancy, and other fields develops towards larger spans, deeper burial, and more complex geological conditions (such as cross-river and cross-sea tunnels, and plateau tunnels), the requirements for the load-bearing capacity, impermeability, and erosion resistance of large-section tunnel lining structures are higher. Existing prefabricated linings are insufficient, necessitating the design and process improvement of new lining structures combining high-performance materials and prefabricated technology. Summary of the Invention

[0003] To address the above-mentioned problems, this invention provides a method for constructing prefabricated lining for large-section tunnels, comprising the following steps:

[0004] S101, prefabricated assembled RPC lining sheet, wherein the assembled RPC lining sheet is an arc-shaped lining sheet, including a reinforcing convex edge and a lining arc surface, wherein a connection sealing reserved structure is provided on the reinforcing convex edge, and a grouting reserved hole is provided on the lining arc surface;

[0005] S201, transport the prefabricated RPC lining sheet to the tunnel construction site;

[0006] S301, the prefabricated RPC lining pieces are assembled using a trolley device. Several prefabricated RPC lining pieces are attached to the tunnel initial lining surface and fixedly connected to each other to form a lining arch. Several lining arches are fixedly connected to each other along the tunnel longitudinal direction to form a tunnel lining structure.

[0007] S401, the joints between the prefabricated RPC lining pieces of the tunnel lining structure are sealed using a sealing process.

[0008] S501, Grouting is performed behind the tunnel lining structure through the grouting pre-reserved holes to fill the gap between the tunnel lining structure and the tunnel initial lining surface, thus completing the prefabricated lining construction of the large-section tunnel.

[0009] As a further explanation of the present invention, the connection sealing reserved structure includes a first sealing ring groove provided along the reinforcing convex edge and bolt holes penetrating the corresponding reinforcing convex edge in the corresponding direction. During the assembly construction of S301, the assembled RPC lining pieces are connected to each other by longitudinal bolts and circumferential bolts, and the assembled RPC lining pieces are sealed to each other by waterproof sealing gaskets.

[0010] Furthermore, the connection sealing reserved structure includes a second sealing ring groove provided along the reinforcing convex edge. The second sealing ring groove is provided with a plurality of reserved grease injection holes communicating to the inner side of the assembled RPC lining plate. The sealing process in step S401 includes roughening the second sealing ring groove and resin casting.

[0011] Furthermore, in step S101, when prefabricating the assembled RPC lining sheet, a pre-embedded bolt hole assembly is provided on the steel reinforcement skeleton of the assembled RPC lining sheet. The pre-embedded bolt hole assembly includes a pre-embedded bolt sleeve and a spiral reinforcement, which is wound and welded to the middle of the outer side of the pre-embedded bolt sleeve.

[0012] Furthermore, in step S101, when prefabricating the assembled RPC lining sheet, a pre-embedded lifting ring assembly is provided on the reinforcing steel skeleton of the assembled RPC lining sheet. The pre-embedded lifting ring assembly includes a lifting ring weld bar and a lifting ring threaded sleeve. The lifting ring weld bar is welded to the reinforcing steel skeleton, and the lifting ring threaded sleeve extends to the surface of the assembled RPC lining sheet. The pre-embedded lifting ring assembly is evenly and symmetrically distributed on the reinforcing steel skeleton of the assembled RPC lining sheet.

[0013] Furthermore, during the hoisting and transportation of the prefabricated RPC lining sheet, the lifting ring is installed on the threaded sleeve of the lifting ring, and the lifting ring is removed before the prefabricated RPC lining sheet is assembled.

[0014] Furthermore, during the assembly of the prefabricated RPC lining sheet, the assembly sleeve is installed on the threaded sleeve of the lifting eye; the trolley device includes an arc track and a track trolley, the track trolley being slidably mounted on the arc track; the track trolley is equipped with a lining sheet telescopic gripping mechanism, the telescopic gripping mechanism including a gripping lever that matches the assembly sleeve.

[0015] Furthermore, the lining sheet telescopic gripping mechanism also includes an arc-shaped plate, and the arc-shaped plate has a through hole corresponding to the gripping lever.

[0016] Furthermore, the assembly sleeve is provided with a T-shaped slot, and the top of the slot is provided with arc-shaped guide parts on both sides. The front end of the gripping lever is provided with a T-shaped clamp corresponding to the slot, and the T-shaped clamp is driven to rotate by the clamp motor at the rear end.

[0017] Furthermore, the prefabricated RPC lining sheet is cast from cement, mineral powder, silica fume, fly ash, manufactured sand, water, water-reducing agent, and steel fiber, with the following mass ratio: 680-700 parts cement, 140-160 parts mineral powder, 170-190 parts silica fume, 95-105 parts fly ash, 950-1050 parts manufactured sand, 165-185 parts water, 26-34 parts water-reducing agent, and 110-125 parts steel fiber. The casting method of the prefabricated RPC lining sheet is as follows: cement, silica fume, fly ash, mineral powder, and manufactured sand are placed in the mixer and dry-mixed until all dry components are evenly mixed; water and water-reducing agent are thoroughly mixed and added to the mixer, and stirred until it becomes a colloidal mixture; steel fiber is added through a vibrating screen feeder and mixed until the steel fiber is evenly dispersed in the slurry, then poured into a hopper and cast through a mold.

[0018] The beneficial effects of this invention are:

[0019] The prefabricated lining construction method for large-section tunnels of the present invention optimizes the design of prefabricated RPC lining segment materials, structure, and supporting construction equipment and processes, resulting in superior structural performance. The compressive strength, flexural strength, and waterproof sealing performance of the lining structure are all improved. Moreover, the structural and process design facilitates assembly and construction. Compared with existing lining construction methods, it has advantages in terms of comprehensive material consumption, construction period, ease of construction, quality, and safety performance, and has great engineering construction application value, especially suitable for the application of large-section tunnel lining structures. Attached Figure Description

[0020] Figure 1 This is a planar structural diagram of the prefabricated RPC lining sheet according to an embodiment of the present invention;

[0021] Figure 2 This is a schematic diagram of the connection and sealing between assembled RPC lining plates according to an embodiment of the present invention;

[0022] Figure 3 This is a schematic diagram of the connection and sealing between assembled RPC lining plates according to another embodiment of the present invention;

[0023] Figure 4 This is a structural diagram of the pre-embedded bolt hole assembly for prefabricated RPC lining sheets according to an embodiment of the present invention;

[0024] Figure 5 This is a structural diagram of the prefabricated RPC lining sheet embedded lifting ring assembly according to an embodiment of the present invention;

[0025] Figure 6 This is a schematic diagram of the hoisting of the prefabricated RPC lining sheet according to an embodiment of the present invention;

[0026] Figure 7 This is a schematic diagram of the overall structure of the trolley device according to an embodiment of the present invention;

[0027] Figure 8 This is a schematic diagram of the track trolley structure according to an embodiment of the present invention;

[0028] Figure 9 This is a schematic diagram of the engagement of the gripping lever and the assembly sleeve in an embodiment of the present invention;

[0029] Figure 10 This is a structural diagram of the lining sheet erection and transportation mechanism according to an embodiment of the present invention.

[0030] Reference numerals: 1. Prefabricated RPC lining plate; 101. Reinforcing protrusion; 102. Lining arc surface; 103. Grouting reserved hole; 104. Bolt hole; 105. Reserved grease injection hole; 2. Waterproof sealing gasket; 3. High-performance epoxy resin material; 4. Embedded bolt sleeve; 5. Wound reinforcing bar; 6. Arc-shaped high-strength bolt; 7. Lifting eye weld bar; 8. Lifting eye threaded sleeve; 9. Lifting eye; 10. Arc track; 11. Track trolley; 12. Lining plate hydraulic clamping mechanism; 13. Tilting bracket; 14. Tilting motor; 15. Transfer chamber; 16. Arc surface plate; 17. Plate through hole; 18. Assembly sleeve; 18. Slot; 181. Arc surface guide part; 19. T-type clamp; 20. Clamp motor; 21. First lead screw; 22. Second lead screw; 23. Detailed Implementation

[0031] Example:

[0032] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0033] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "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 invention 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 invention.

[0034] This embodiment of a prefabricated lining construction method for large-section tunnels includes the following steps:

[0035] S101, prefabricated assembled RPC lining sheet 1, the assembled RPC lining sheet 1 is an arc-shaped lining sheet, including a reinforcing protrusion 101 and a lining arc surface 102, the reinforcing protrusion 101 is provided with a connection sealing reserved structure, and the lining arc surface 102 is provided with a grouting reserved hole 103.

[0036] S201, transport the prefabricated RPC lining sheet 1 to the tunnel construction site;

[0037] S301, the prefabricated RPC lining pieces 1 are assembled using a trolley device. Several prefabricated RPC lining pieces 1 are attached to the tunnel initial lining surface and fixedly connected to each other to form a lining arch. Several lining arches are fixedly connected to each other along the tunnel longitudinal direction to form a tunnel lining structure.

[0038] S401, the joints between the prefabricated RPC lining pieces 1 of the tunnel lining structure are sealed using a sealing process.

[0039] S501, Grouting is performed behind the tunnel lining structure through the grouting pre-reserved hole 103 to fill the gap between the tunnel lining structure and the tunnel initial lining surface, thus completing the prefabricated lining construction of the large-section tunnel.

[0040] The prefabricated lining construction method for large-section tunnels of the present invention optimizes the design of prefabricated RPC lining segment materials, structure, and supporting construction equipment and processes, resulting in superior structural performance. The compressive strength, flexural strength, and waterproof sealing performance of the lining structure are all improved. Moreover, the structural and process design facilitates assembly and construction. Compared with existing lining construction methods, it has advantages in terms of comprehensive material consumption, construction period, ease of construction, quality, and safety performance, and has great engineering construction application value, especially suitable for the application of large-section tunnel lining structures.

[0041] For details, please see the appendix. Figure 2 As shown, the connection sealing reserved structure includes a first sealing ring groove along the reinforcing protrusion 101 and bolt holes 104 penetrating the corresponding reinforcing protrusion 101 in the corresponding direction. During the assembly construction of S301, the prefabricated RPC lining pieces 1 are connected to each other by longitudinal bolts and circumferential bolts, and the prefabricated RPC lining pieces 1 are sealed to each other by waterproof sealing gaskets 2. In actual assembly, a certain gap is reserved between the prefabricated RPC lining pieces 1 to allow the waterproof sealing gaskets 2 to contact and compress, ensuring the waterproof sealing effect.

[0042] See appendix Figure 3In the illustrated embodiment, the pre-reserved sealing structure includes a second sealing ring groove along the reinforcing convex edge 101. The second sealing ring groove has a plurality of pre-reserved grease injection holes 105 communicating with the inner side of the assembled RPC liner 1. The sealing process in step S401 includes roughening the second sealing ring groove and resin casting. Before assembling the assembled RPC liner 1, the corresponding surface of the assembled RPC liner 1 is roughened, for example, by high-speed jet impact roughening of the surface using hard abrasives such as steel shot or corundum. After the assembled RPC liner 1 is assembled, high-performance epoxy resin material 3 is injected into the pre-reserved cavity between the connecting surfaces of adjacent segments. After curing, the segments are firmly bonded into a continuous and uniform integral structure. The high-performance epoxy resin material 3, after curing, has compressive strength, flexural strength, and elastic modulus that match the prefabricated RPC lining sheet 1, ensuring effective force transmission. This transforms the point contact between the prefabricated RPC lining sheets 1 into surface contact, resulting in a more uniform stress distribution and significantly improving the overall performance of the lining. It also significantly enhances the stiffness, bending resistance, and shear resistance of the lining ring, particularly improving joint opening and misalignment issues. Epoxy resin itself is a dense, impermeable material, and after curing, it forms a continuous, seamless connection at the joints, preventing water seepage and achieving a high-strength, leak-free tunnel lining structure.

[0043] In the preferred embodiment, as shown in the appendix Figure 4 As shown, in step S101, when prefabricating the assembled RPC lining sheet 1, a pre-embedded bolt hole assembly is provided on the reinforcing steel skeleton of the assembled RPC lining sheet 1. The pre-embedded bolt hole assembly includes a pre-embedded bolt sleeve 4 and a spiral reinforcing steel bar 5. The spiral reinforcing steel bar 5 is wound and welded to the middle of the outer side of the pre-embedded bolt sleeve 4. In this embodiment, the pre-embedded bolt sleeve 4 is an arc-shaped metal sleeve. The assembled RPC lining sheets 1 are connected by arc-shaped high-strength bolts 6. The pre-embedded bolt sleeve 4 is pre-embedded and connected to the embedded reinforcing steel bar of the assembled RPC lining sheet 1 through the spiral reinforcing steel bar 5, ensuring the strength of the connection structure.

[0044] Specifically, in this embodiment, during step S101 of prefabricating the assembled RPC lining sheet 1, a pre-embedded lifting ring assembly is provided on the reinforcing steel skeleton of the assembled RPC lining sheet 1. The pre-embedded lifting ring assembly includes a lifting ring weld bar 7 and a lifting ring threaded sleeve 8. The lifting ring weld bar 7 is welded to the reinforcing steel skeleton, and the lifting ring threaded sleeve 8 extends to the surface of the assembled RPC lining sheet 1. The pre-embedded lifting ring assembly is evenly and symmetrically distributed on the reinforcing steel skeleton of the assembled RPC lining sheet 1. (See attached figure) Figure 6As shown, after the prefabricated RPC lining sheet 1 is cast and reaches a certain strength, a lifting ring 9 is installed on the prefabricated RPC lining sheet 1 for hoisting and transportation. In this embodiment, the lifting ring threaded sleeve 8 is a metal sleeve pre-embedded inside the prefabricated RPC lining sheet 1. It is welded to the reinforcing steel frame via the lifting ring weld bar 7 to ensure structural strength and prevent easy damage to the prefabricated RPC lining sheet 1 during hoisting and transportation. The lifting ring threaded sleeve 8 vertically penetrates the prefabricated RPC lining sheet and has internal threads. A lifting ring 9 with a matching screw can be screwed and fixed inside the lifting ring threaded sleeve 8 as a lifting point. (See attached diagram.) Figure 6 The four evenly distributed lifting rings 9 shown ensure uniform force distribution during the hoisting of the prefabricated RPC lining sheet 1, thus ensuring stability during the hoisting and transportation process. The lifting rings 9 can be removed before assembling the prefabricated RPC lining sheet 1.

[0045] On the other hand, the pre-embedded lifting eye assembly can also assist in the assembly of the prefabricated RPC liner 1 by installing the assembly sleeve 18 on the lifting eye threaded sleeve 8. Similarly, the assembly sleeve 18 is an assembly sleeve 18 with a matching screw, which is tightened and fixed to the prefabricated RPC liner 1 as a fixing point. See Appendix Figure 7 As shown, the trolley device in this embodiment includes an arc track 10 and a track trolley 11, with the track trolley 11 slidably mounted on the arc track 10. The track trolley 11 is equipped with a lining sheet telescopic gripping mechanism, which includes a gripping lever that matches the assembly sleeve 18. In practical applications, the trolley device also includes a lining sheet erection and transport mechanism and a lining sheet hydraulic clamping mechanism 12. The lining sheet erection and transport mechanism is used for flipping and erecting the lining sheets and for transporting them, while the lining sheet hydraulic clamping mechanism 12 is used for clamping and positioning the lining sheets during assembly. During assembly, the prefabricated RPC lining piece 1 is placed on the flipping bracket 13 of the lining piece erection and transport mechanism. Under the traction of the flipping motor 14, the flipping bracket 13 drives the prefabricated RPC lining piece 1 to stand up and enter the transfer chamber 15. The transfer chamber 15 moves along the track to transport the prefabricated RPC lining piece 1 to the position of the corresponding arc track 10. The track trolley 11 then runs to the corresponding position, grabs the prefabricated RPC lining piece 1 by the action of the grabbing lever, and transports the prefabricated RPC lining piece 1 to the assembly position along the arc track 10.

[0046] Specifically, the lining sheet telescopic gripping mechanism also includes an arc-shaped plate 16, on which a through hole 17 is provided corresponding to the gripping lever. During transportation, the arc-shaped plate 16 fits against the inner surface of the assembled RPC lining sheet 1, serving a positioning and limiting function. After positioning, the gripping lever extends forward under the action of the first lead screw 22, allowing the gripping lever to pass through the through hole 17 and insert into the assembly sleeve 18 on the assembled RPC lining sheet 1 for clamping and fixing, so that the rail trolley 11 can smoothly transport the assembled RPC lining sheet 1 to the assembly position along the arc track 10.

[0047] For details, see attached. Figure 9 As shown, the assembly sleeve 18 of this embodiment is provided with a slot 181 with a T-shaped cross section. The top two sides of the slot 181 are provided with arc-shaped guide parts 19. The front end of the gripping lever is provided with a T-shaped clamp 20 corresponding to the slot 181. The T-shaped clamp 20 is driven to rotate by the clamp motor 21 at the rear end. During the specific operation, after the assembled RPC lining piece 1 is transported to its position by the transfer chamber 15, the first lead screw 22 first drives the T-shaped clamp 20 to extend forward and insert into the assembly sleeve 18. At this time, the T-shaped clamp 20 can rotate freely and automatically rotate to a suitable position under the guidance of the arc-shaped guide part 19 so that the T-shaped clamp 20 can be inserted into the bottom of the assembly sleeve 18. After the T-shaped clamp 20 is inserted into place, the clamp motor 21 drives it to rotate at a certain angle (e.g., 90 degrees). Then, the first lead screw 22 moves again to pull the T-shaped clamp 20 back to lock it in place. Under the opposite action of the T-shaped clamp 20 and the arc-shaped plate 16, the assembled RPC lining piece 1 is fastened. The trolley 11 moves along the arc track 10 to transport the prefabricated RPC lining piece 1 to the assembly position. The telescopic gripping mechanism extends forward under the action of the second lead screw 23, supporting the prefabricated RPC lining piece 1 at the assembly position. Subsequently, the hydraulic clamping mechanism 12 of the lining piece at the corresponding position of the trolley device actuates to support and fix the prefabricated RPC lining piece 1 for subsequent assembly construction. After the prefabricated RPC lining piece 1 is supported and fixed by the hydraulic clamping mechanism 12, the first lead screw 22 actuates to release the T-shaped clamp 20. Then, the clamp motor 21 rotates in the opposite direction according to the recorded rotation amount, allowing the T-shaped clamp 20 to disengage from the slot 181 of the assembly sleeve 18. The second lead screw 23 actuates to reset, and the trolley 11 then performs the gripping and transporting of the next prefabricated RPC lining piece 1.

[0048] The prefabricated RPC lining sheet 1 of the present invention is cast from cement, mineral powder, silica fume, fly ash, manufactured sand, water, water-reducing agent, and steel fiber. Specifically, in this embodiment, the prefabricated RPC lining sheet 1 is cast according to the following mass ratio: 700 parts cement, 150 parts mineral powder, 180 parts silica fume, 100 parts fly ash, 1004 parts manufactured sand, 179 parts water, 29.4 parts water-reducing agent, and 117 parts steel fiber. The casting method of the prefabricated RPC lining sheet 1 is as follows: cement, silica fume, fly ash, mineral powder, and manufactured sand are placed in the mixer and dry-mixed until the dry components are evenly mixed; water and water-reducing agent are thoroughly mixed and added to the mixer, and stirred until it becomes a colloidal mixture; steel fiber is added through a vibrating screen feeder and mixed until the steel fiber is evenly dispersed in the slurry, then poured into a hopper and cast through a mold.

[0049] Steel fibers are a key component for achieving high toughness in RPC (Reinforced Polymer Cement), but their slender shape makes them prone to clumping due to uneven stress during addition. When steel fibers are initially added simultaneously with cement and aggregates, or added too early, the material system contains a large amount of dry powder. The steel fibers are easily adsorbed by the powder and become entangled, forming difficult-to-disperse clumps. This clumping severely damages the uniformity of the RPC material: the clumped areas have dense steel fibers, while surrounding areas may lack reinforcement. This causes stress concentration at the clumped areas, preventing the bridging effect of the steel fibers from dispersing the load, thus resulting in substandard compressive strength, flexural strength, and other mechanical properties of the precast lining structure. To address this, this invention sets the steel fiber addition time after all dry materials and water have been thoroughly mixed. At this point, the material system has formed a slurry with a certain degree of fluidity, reducing the adsorption force between steel fibers and lowering the probability of clumping. A special mesh screen with a 3mm aperture is used as the steel fiber addition channel, and a small vibrator is equipped above the screen. During feeding, the steel fibers fall through the screen, and the high-frequency vibration generated by the vibrator causes the steel fibers to disperse and pass through the screen holes, effectively breaking up potential agglomerations. At the same time, the vibration can prevent the steel fibers from accumulating on the screen surface, ensuring a continuous and smooth feeding process and achieving uniform distribution of steel fibers in the RPC slurry.

[0050] This invention employs a stepped addition process: dry powder pre-mixing → water addition and mixing → admixture addition → steel fiber addition. First, dry materials such as silica fume, cement, mineral powder, manufactured sand, and fly ash are mixed for 1-2 minutes to achieve initial homogeneity. Then, mixing water and admixtures are slowly added in proportion, and the mixture is stirred for 2-5 minutes to improve slurry fluidity. Finally, steel fibers are added and stirred for 1-2 minutes to ensure overall uniformity. Based on the RPC material ratio, the optimal total mixing time of 8-12 minutes is determined through preliminary trial mixing to avoid abnormal fluidity caused by mixing too short or too long.

[0051] The above description only illustrates preferred embodiments of the present invention and should not be construed as limiting the scope of the claims. The present invention is not limited to the above embodiments, and variations in its specific structure are permitted. In short, all variations made within the scope of the independent claims of the present invention are within the scope of protection of the present invention.

Claims

1. A method for constructing prefabricated lining for large-section tunnels, characterized in that, Includes the following steps: S101, prefabricated assembled RPC lining sheet, wherein the assembled RPC lining sheet is an arc-shaped lining sheet, including a reinforcing convex edge and a lining arc surface, wherein a connection sealing reserved structure is provided on the reinforcing convex edge, and a grouting reserved hole is provided on the lining arc surface; S201, transport the prefabricated RPC lining sheet to the tunnel construction site; S301, the prefabricated RPC lining pieces are assembled using a trolley device. Several prefabricated RPC lining pieces are attached to the tunnel initial lining surface and fixedly connected to each other to form a lining arch. Several lining arches are fixedly connected to each other along the tunnel longitudinal direction to form a tunnel lining structure. S401, the joints between the prefabricated RPC lining pieces of the tunnel lining structure are sealed using a sealing process. S501, Grouting is performed behind the tunnel lining structure through the grouting pre-reserved holes to fill the gap between the tunnel lining structure and the tunnel initial lining surface, thus completing the prefabricated lining construction of the large-section tunnel. The connection sealing reserved structure includes a first sealing ring groove provided along the reinforcing convex edge and bolt holes penetrating the corresponding reinforcing convex edge in the corresponding direction. During the assembly construction of S301, the prefabricated RPC lining pieces are connected to each other by longitudinal bolts and circumferential bolts, and the prefabricated RPC lining pieces are sealed to each other by waterproof sealing gaskets. The connection sealing reserved structure includes a second sealing ring groove provided along the reinforcing convex edge. The second sealing ring groove is provided with a plurality of reserved grease injection holes communicating to the inner side of the assembled RPC lining plate. The sealing process in step S401 includes roughening the second sealing ring groove and resin casting. In step S101, when prefabricating the assembled RPC lining sheet, a pre-embedded lifting ring assembly is set on the steel reinforcement skeleton of the assembled RPC lining sheet. The pre-embedded lifting ring assembly includes a lifting ring weld bar and a lifting ring threaded sleeve. The lifting ring weld bar is welded to the steel reinforcement skeleton, and the lifting ring threaded sleeve extends to the surface of the assembled RPC lining sheet. The pre-embedded lifting ring assembly is evenly and symmetrically distributed on the steel reinforcement skeleton of the assembled RPC lining sheet. When assembling the prefabricated RPC lining sheet, the assembly sleeve is installed on the lifting eye threaded sleeve; the trolley device includes an arc track and a track trolley, the track trolley is slidably arranged on the arc track; the track trolley is provided with a lining sheet telescopic gripping mechanism, the telescopic gripping mechanism includes a gripping lever that matches the assembly sleeve; The assembly sleeve is provided with a T-shaped slot, and the top of the slot is provided with arc-shaped guide parts on both sides. The front end of the gripping lever is provided with a T-shaped clamp corresponding to the slot, and the T-shaped clamp is driven to rotate by the clamp motor at the rear end. The prefabricated RPC lining sheet is cast from cement, mineral powder, silica fume, fly ash, manufactured sand, water, water-reducing agent, and steel fiber, with the following mass ratio: 680-700 parts cement, 140-160 parts mineral powder, 170-190 parts silica fume, 95-105 parts fly ash, 950-1050 parts manufactured sand, 165-185 parts water, 26-34 parts water-reducing agent, and 110-125 parts steel fiber. The casting method for the prefabricated RPC lining sheet is as follows: Cement, silica fume, fly ash, mineral powder, and manufactured sand are dry-mixed in the mixer until all dry components are evenly mixed. Water and water-reducing agent are thoroughly mixed and added to the mixer, then stirred until it becomes a colloidal mixture. Steel fiber is added through a vibrating screen feeder and mixed until the steel fiber is evenly dispersed in the slurry. The mixture is then poured into a hopper and cast through a mold.

2. The prefabricated lining construction method for large-section tunnels according to claim 1, characterized in that: In step S101, when prefabricating the assembled RPC lining sheet, a pre-embedded bolt hole assembly is set on the steel reinforcement skeleton of the assembled RPC lining sheet. The pre-embedded bolt hole assembly includes a pre-embedded bolt sleeve and a spiral reinforcement. The spiral reinforcement is wound and welded to the middle of the outer side of the pre-embedded bolt sleeve.

3. The prefabricated lining construction method for large-section tunnels according to claim 1, characterized in that: During the hoisting and transportation of the prefabricated RPC lining sheet, the lifting ring is installed on the threaded sleeve of the lifting ring, and the lifting ring is removed before the prefabricated RPC lining sheet is assembled.

4. The prefabricated lining construction method for large-section tunnels according to claim 1, characterized in that: The lining sheet telescopic gripping mechanism also includes an arc-shaped plate, and the arc-shaped plate has a through hole corresponding to the gripping lever.

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