Construction method for rapid recovery of existing tunnel lining

Abstract

The invention belongs to the technical field of tunnel construction, and particularly relates to a construction method for rapidly recovering an existing tunnel lining. In order to achieve rapid recovery of the existing tunnel, operation sections are partitioned, a tunnel inverted arch double-trestle opposite logistics method is adopted, synchronous construction of a secondary lining area, a double-inverted arch trestle area and an expanding excavation area is achieved, the logistics efficiency of all construction areas is improved, and the technical problem of transportation of materials in multiple working face holes of the tunnel is solved. A tunnel full-section waterproof plate paving and hanging structure and a lining buffer layer paving and hanging structure are combined, so that the construction speed of a waterproof plate and a buffer cushion layer is effectively increased; by combining a sliding groove window-by-window layered pouring construction technology, window-by-window rapid feeding of secondary lining arch wall concrete is achieved, the tunnel secondary lining concrete pouring speed is increased through mechanical window-by-window layered pouring, maintenance is conducted through a movable fog gun and a moisturizing film in the later period, and the overall quality of secondary lining concrete construction is ensured.

Description

Technical Field

[0001] The invention belongs to the technical field of tunnel construction, and in particular relates to a method for quickly restoring an existing tunnel lining. Background Art

[0002] At present, the operating mileage of domestic highway and railway tunnels continues to grow. During the construction or operation of some tunnels, due to reasons such as geology, construction quality, repeated loads from operating vehicles, etc., serious cracks in the lining, inward extrusion, and ballast uplift are found in many places of the tunnel, which do not meet the requirements for safe operation of the tunnel; or during the construction stage, due to high ground stress or the tectonic action of active faults, some of the completed inverts can no longer bear loads or are affected in use, and the diseased sections need to be completely replaced.

[0003] For the above-mentioned tunnel special geological disaster emergency rescue project, in order to realize the expansion of a single tunnel and a single line in a short period of time and resume operation, it is necessary to carry out construction on multiple working surfaces simultaneously. Faced with numerous lining restoration construction processes, there are problems such as mutual interference among the processes, extremely difficult organization of logistics in the tunnel, and difficult construction organization and management. Summary of the invention

[0004] The purpose of the present invention is to provide a method for quickly restoring the lining of an existing tunnel in view of the technical problems of difficulty in transporting materials in multiple working faces of a tunnel and slow construction progress in the prior art.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] A method for rapid restoration of existing tunnel lining, comprising the following steps:

[0007] Step 1: Divide the main tunnel operation section into sections and carry out tunnel invert construction;

[0008] The subdivision includes four sections: along the length direction of the main tunnel operation section, there are the second lining section, the first trestle section, the second trestle section and the expansion section, and the interval between adjacent sections is 20-50m; the tunnel invert construction is carried out simultaneously in the first trestle section and the second trestle section;

[0009] Step 2: Lay and hang waterproof panels on the entire tunnel section in the main tunnel operation section;

[0010] Step 3: After the waterproof board is laid, the lining reinforcement is constructed; first, the positioning reinforcement is constructed, and the annular reinforcement and the longitudinal distribution reinforcement are installed according to the positioning reinforcement, and finally the connection reinforcement between the two layers of reinforcement is installed;

[0011] Step 4: construct the longitudinal annular waterstop, including overlapping the longitudinal annular waterstop;

[0012] Step 5: Lining casting and curing. The lining is constructed using a hydraulic steel mold integral lining trolley. The secondary lining is constructed using a large arc-shaped steel mold lining trolley. The arch wall is molded in one step.

[0013] Step 6: Repeat steps 1 to 5 to complete the restoration of all tunnel linings.

[0014] In the technical solution of the present invention, in order to achieve rapid recovery of existing tunnels, the tunnel invert double trestles counter-logistics method is adopted to achieve simultaneous construction of the secondary lining area, double invert trestles area, and expansion area, thereby improving the logistics efficiency of each construction area and solving the technical problem of material transportation in multiple working faces of the tunnel. Combined with the tunnel full-section waterproof board paving and hanging structure and the lining buffer layer paving and hanging structure, the construction speed of the waterproof board and the buffer layer is effectively improved; combined with the chute window-by-window layered pouring construction method, the second lining arch wall concrete is quickly fed window by window, and the mechanical window-by-window layered pouring improves the pouring speed of the tunnel secondary lining concrete. In the later stage, mobile fog cannons and moisturizing films are used for maintenance to ensure the overall quality of the second lining concrete construction.

[0015] As a preferred solution of the present invention, in step 1, the front end of the main tunnel operation section is provided with a first transverse passage, and the rear end of the main tunnel operation section is provided with a second transverse passage. The logistics transportation of the first trestle area is carried out through the first transverse passage, and the logistics transportation of the second trestle area is carried out through the second transverse passage. The first transverse passage is connected to the second transverse passage through a horizontal guide parallel to the main tunnel.

[0016] The first transverse passage is close to the secondary lining construction area, and the second transverse passage is close to the expansion excavation area.

[0017] Preferably, the invert construction processes of the first trestle area and the second trestle area are carried out simultaneously, with opposite logistics directions, and the logistics conveying direction during the invert construction of the expansion area is the same as that of the first trestle area.

[0018] Preferably, the distance between the inverts corresponding to the first pier area and the second pier area is 20-24m.

[0019] As a preferred solution of the present invention, in step 1, the tunnel invert construction specifically includes:

[0020] Initial support and pouring of the invert are performed in the first trestle area and the second trestle area respectively.

[0021] As a preferred embodiment of the present invention, in step 2, the waterproof board laying and hanging step is:

[0022] a. First, install anchor steel bars on the side walls on both sides of the tunnel, with an anchor depth of 40 cm;

[0023] b. Then set a clamp point every 60cm along the longitudinal length of the waterproof board. The length of the waterproof board clamp is 3m, and a total of 4 clamp points are set. Then lay it from one side to the other.

[0024] c. Similarly, use the waterproof board clamp to clamp the other end of the waterproof board on the other side.

[0025] d. After the waterproof board fixture is adjusted into place, use a ladder to ultrasonically weld the waterproof board.

[0026] As a preferred solution of the present invention, after the waterproof board is installed, the inverted arch formwork is installed, and the inverted arch concrete is poured and maintained. After the inverted arch construction is completed, the trestle is dismantled.

[0027] Preferably, in step 4, the longitudinal annular waterstop overlap construction process is specifically as follows:

[0028] S1. First, cut off the rubber of the lapped raised part of the steel edge rubber water stop;

[0029] S2. Then put the steel plate waterstop and the steel edge rubber waterstop together, and anchor them with at least two rivets on each side;

[0030] S3. After the rivets are anchored, the gap between the steel-edge rubber waterstop and the steel plate waterstop is tightly bonded with adhesive material.

[0031] Preferably, in step 5, the lining pouring construction process is specifically as follows: firstly roughening the concrete surface, then constructing the buffer cushion layer, and finally pouring the lining windows.

[0032] Preferably, before constructing the buffer layer, the center line of the bottom edge of the buffer layer, the center line of the annular hose and the center line of the drainage strip are marked on the initial support surface. The bottom edge of the buffer layer is the rail top elevation. The annular hose and the annular drainage strip are arranged alternately. The buffer layer is laid between adjacent annular hoses. In the longitudinal and annular directions, multiple dovetail clamps are arranged between two adjacent buffer layers.

[0033] Preferably, the buffer layer is made of polyethylene.

[0034] Preferably, the lining is cast layer by layer by chute, and a lining trolley is used for the lining casting. A grading and diversion device is provided on the lining trolley. The grading and diversion device includes multi-stage diversion components from top to bottom, and each multi-stage diversion component includes a main hopper, a main trough, a three-way diversion trough, a diversion string tube and a window inlet trough.

[0035] Preferably, the lining is poured in layers symmetrically from bottom to top with layered vibration, and a low-frequency vibrator and a high-frequency vibrator are used in combination during the concrete consolidation process.

[0036] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0037] 1. In the technical solution of the present invention, by proposing a tunnel invert double-trestle counter-logistics mode and an invert double-channel construction method, the synchronous construction of the secondary lining area, the double invert trestle area, and the expansion area is achieved, which greatly improves the logistics efficiency of each construction section and overcomes the problem of material transportation in multiple working faces of small-section and short-interval tunnels.

[0038] 2. The technical solution of the present invention is combined with the construction of waterproof board hanging structure for the whole section of the tunnel on the basis of the synchronous construction of multiple sections. The lining buffer layer hanging construction effectively improves the waterproof effect of the overlapping position of the waterproof board. In the process of pouring the second lining, the second lining trolley is combined with the graded diversion device to realize the rapid feeding of the whole section of the tunnel window by window, and improve the rapid recovery of the second lining. After the pouring of the second lining is completed, it is further combined with the maintenance methods of high and low frequency vibration, mobile fog cannon and moisturizing film to ensure the final construction quality of the second lining. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a construction flow chart of the present invention;

[0040] Figure 2 It is a zoning schematic diagram of the main tunnel operation section of the present invention;

[0041] Figure 3 It is a logistics transportation route map during the tunnel invert construction process of the present invention;

[0042] Figure 4 It is a schematic diagram of the waterproof board laying and hanging structure of the present invention;

[0043] Figure 5 It is a schematic diagram of the hanging structure of the present invention;

[0044] Figure 6 It is a schematic diagram of the clamp structure of the waterproof board laying and hanging structure of the present invention;

[0045] Figure 7 It is a schematic diagram of the overlap of the longitudinal annular waterstop of the present invention;

[0046] Figure 8 It is a schematic diagram of the structure of the cushion layer of the present invention;

[0047] Fig. 9 It is a schematic diagram of the structure of the dovetail clamp of the present invention;

[0048] Fig.10 It is a schematic diagram of the grading and diversion device of the present invention;

[0049] Icons: 1-first transverse channel; 2-second transverse channel; 3-second lining area; 4-first trestle area; 5-second trestle area; 6-expansion area; 7-steel pipe; 8-clamp; 9-waterproof board; 10-adjusting bolt; 11-anchor bolt; 12-steel plate waterstop; 13-steel edge rubber waterstop; 14-longitudinal construction joint; 15-drainage board belt; 16-circumferential hose; 17-buffer cushion; 18-dovetail clamp;

[0050] 19-main hopper; 20-main flow channel; 21-three-way diversion channel; 22 diversion string tube; 23-window flow channel. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0052] Example 1

[0053] This embodiment is explained in conjunction with a specific case, and the method of this embodiment is successfully applied to a special geological disaster emergency rescue project in a certain mountain and a certain tunnel;

[0054] Project Overview

[0055] The entrance of a tunnel on the Wanji Line Railway is located in Pu County, and the exit is located at the junction of Yaodu District, Linfen City and Hongdong County. It is designed as a double-hole single-track tunnel with a total length of 23,468.5 meters for the upline and 23,441 meters for the downline. After the tunnel was opened for operation, geological disasters such as severe cracking of the lining, inward extrusion, and ballast uplift were found in the tunnel many times. After monitoring and observation, the disease continued to develop and the sections continued to increase. After demonstration by the expert meeting, it was clarified that the disaster in a certain tunnel was mainly caused by special geological disaster factors such as complex geological structure, groundwater changes, and gypsum-salt rock. It was necessary to fully dismantle and replace the diseased sections, and dynamically adjust the special sections and measures according to the monitoring situation during the construction process.

[0056] A method for rapid restoration of existing tunnel linings, combining the overall construction process Figure 1 It is understood that the initial support section is inspected and reviewed before construction, and the tunnel centerline, level, section size and clearance size meet the design requirements to ensure that the lining does not intrude into the tunnel construction limits.

[0057] The specific steps include:

[0058] Step 1, divide the main tunnel operation section into zones to carry out tunnel invert construction; the main tunnel operation section is located between two transverse passages, and the zones include four sections: along the length direction of the main tunnel operation section, there are the second lining section 3, the first trestle section 4, the second trestle section 5 and the expansion section 6, wherein the first transverse passage 1 is arranged near the second lining section 3, and the second transverse passage 2 is arranged near the expansion section 6. Figure 2 It is a zoning diagram of the main tunnel working section, in which the first transverse channel 1 and the second transverse channel 2 are connected by a horizontal guide parallel to the main tunnel.

[0059] The interval between adjacent sections is 20-50m; the invert support is 14m (support 3m / cycle), casting is 12m, and the distance between two inverts is 24m.

[0060] In this embodiment, by taking the flat guide as the main transport channel, adding a cross channel to connect the flat guide and the expansion line, priority is given to constructing a parallel auxiliary guide pit through the main tunnel, and after completion, the main tunnel is constructed through the parallel auxiliary guide pit. By setting up multiple short construction work sections, and constructing the work sections in both directions, the construction work surface is increased, and the construction progress is accelerated through clustered short-distance work surface rapid construction.

[0061] like Figure 3 The figure shows a logistics transportation route map during the tunnel invert construction process. During the tunnel invert construction process, the first trestle area 4 and the second trestle area 5 are carried out simultaneously, and the logistics transportation directions are opposite. Among them, the logistics organization direction of the expansion area 6 is the same as that of the first trestle area 4. Concrete and steel frame transportation are transported from the first transverse channel 1 to each construction operation section.

[0062] The invert reinforcement arrangement and mucking of the first trestle area 4 are carried out through the first transverse passage 1 after passing through the second lining area 3;

[0063] The second trestle area 5 inverted arch reinforcement setting and mucking are carried out through the second cross channel 2 after passing through the expansion area 6;

[0064] The excavation area 6 is excavated through the second trestle area 5, the first trestle area 4, the second lining construction area, and then transported through the first transverse passage 1; the excavation of the invert is preceded by drilling and blasting and leveling the site, and the excavation drilling and blasting are carried out simultaneously without considering the time consumption of the excavation drilling and blasting. Figure 3 shown.

[0065] The expansion area 6 is used for rapid removal of the existing tunnel lining concrete.

[0066] In this embodiment, the tunnel primary branch adopts anti-seepage sulfate shotcrete and wet shotcrete.

[0067] In the process of organizing the logistics of the double-trestled invert bridge, we need to pay attention to the following:

[0068] a. Excavation and ballast removal of the secondary lining must start after the invert trestle is returned to its position;

[0069] b. When the invert is being excavated and slag is being removed, mucking and anchor spraying operations cannot be carried out in the excavation area 6.

[0070] c. The excavator is parked in the close-range cross passage area;

[0071] d. The steel frames, steel meshes, anchor rods, locking anchor pipes and other materials for expanding the excavation surface should arrive near the working area before the invert is mucking out.

[0072] Step 2: Lay and hang waterproof panels 9 on the entire tunnel section of the main tunnel operation section; specifically, the waterproof panels 9 are laid and hung with reference to Figure 4 As shown, the waterproof board 9 laying process is specifically as follows:

[0073] ①First, install Φ22 anchor steel bars on the side wall, anchoring 40cm. The specific hanging structure is as follows: Figure 5 As shown,

[0074] ② Then set a clamp 8 point every 60cm along the waterproof board 9. The length of the clamp 8 of the waterproof board 9 is 3m, and a total of 4 clamp points are set. Then lay it from one side to the other. The form of the clamp 8 of the waterproof board 9 is as follows Figure 6 As shown;

[0075] ③ Similarly, use the waterproof board 9 clamp 8 to clamp the other end of the waterproof board 9 on the other side;

[0076] ④ After the waterproof board 9 fixture 8 is adjusted into place, the waterproof board 9 is welded by ultrasonic welding using a ladder.

[0077] Step 3: After the waterproof board 9 is laid, lining steel bars are constructed;

[0078] After the waterproof board 9 is laid, the steel bars are tied. The steel bars used in this project are all processed and formed in the processing plant and then transported to the site for use. First, the positioning steel bars are constructed, and the annular steel bars and longitudinal distribution steel bars are installed according to the positioning steel bars. Finally, the connecting bars between the two layers of steel bars are installed.

[0079] After waterproof board 9 is laid, also comprise the installation of inverted arch formwork, and carry out inverted arch concrete pouring, maintenance.After inverted arch construction is completed, remove the trestle.

[0080] Step 4: construct the longitudinal annular waterstop;

[0081] Since the rubber part of the steel edge rubber water stop 13 is raised, and the groove of the steel plate water stop 12 faces the primary support surface, the longitudinal construction joint 14 steel plate water stop 12 and the annular steel edge rubber water stop 13 cannot be tightly attached when they are overlapped, and there is a large gap in the middle, which is a weak link in waterproofing. It is necessary to strengthen the overlapping construction of the annular longitudinal water stop. For specific settings, see Figure 7As shown, the lap joint construction sequence is as follows:

[0082] ① First, cut off the rubber of the overlapping raised part of the steel edge rubber water stop 13;

[0083] ② Then put the steel plate water stop 12 and the steel edge rubber water stop 13 together, and anchor them with 3 rivets on each side.

[0084] ③ After the rivets are anchored, the gap between the steel edge rubber water stop 13 and the steel plate water stop 12 is bonded tightly with adhesive material.

[0085] Step 5: Casting and curing of secondary lining; the lining adopts hydraulic steel mold integral lining trolley, the secondary lining adopts large arc-shaped steel mold lining gantry, and the arch wall is molded in one step;

[0086] Before constructing the buffer layer 17, mark the center line of the bottom edge of the buffer layer 17, the center line of the annular hose 16 and the center line of the drainage strip 15 on the initial support surface. The bottom edge of the buffer layer 17 is the rail top elevation. The annular hose 16 and the annular drainage strip 15 are arranged alternately. The buffer layer is laid between adjacent annular hoses 16. In the longitudinal and annular directions, multiple dovetail clamps are arranged between two adjacent buffer layers 17.

[0087] Specifically, the steps include:

[0088] 1. Roughening the concrete surface: Specific construction process: pouring concrete → spraying retarder (slurry raising is completed) → roughening (washing with high-pressure water gun) → cleaning the interface (removing accumulated water and waste residue);

[0089] Concrete pouring is carried out according to the concrete construction process. Spray retarder, treat the interface between the second lining end and the invert end, and spray retarder on the end formwork before closing the formwork. Spray retarder on the top surface of the small side wall immediately after the concrete slurry is completed (retarder spraying is completed within 20 minutes). Rinse, use a high-pressure water gun to high-pressure wash the concrete interface 6 to 8 hours after the initial setting of the concrete or pouring. Clean the interface and remove the accumulated water and waste residue on the construction interface.

[0090] 2. Construction of polyethylene cushion layer 17 (5 cm thick);

[0091] The buffer layer is made of polyethylene foam board with a thickness of 50mm. It is set on the side wall and the arch. The polyethylene buffer layer is processed in blocks with a processing size of 1.5m*1.5m and a thickness of 50mm. It is fixed with dovetail clamps.

[0092] like Figure 8-9 As shown;

[0093] ① Alignment: Use red paint to spray the bottom edge of the buffer layer 17 and the center line of the annular hose 16 and the drainage strip 15 on the primary support surface. The bottom edge of the buffer layer is the rail top elevation, and the annular hose 16 and the annular drainage strip 15 are arranged alternately, with a center line spacing of 1.6m;

[0094] ②Install the bottom dovetail clamps: the size of the buffer layer material is 0.75m*1.5m, and the dovetail clamp spacing is 81cm*78cm (longitudinal direction of the ring).

[0095] A buffer layer is laid between adjacent annular hoses 16 at a clear distance of 3m. The size of the buffer layer 17 is 0.75m high×(1.5+1.5)m wide, with 39-40cm reserved at both ends. The spacing between dovetail clips 18 is 77cm, with four each on the top and bottom.

[0096] ③Install the polyethylene buffer layer. Install one dovetail clip and one buffer layer from bottom to top.

[0097] ④ The bottom two layers of the buffer layer are laid using a ladder before the inverted arch waterproofing board 9 is laid, and the upper part is constructed using a scaffold after the inverted arch and the inverted arch filling are poured.

[0098] 3. Casting of lining windows; the lining is cast in layers by window using a chute, and a lining trolley is used for casting the lining. A graded and diverted device is provided on the lining trolley. The graded and diverted device includes multi-stage diverted components from top to bottom, and each multi-stage diverted component includes a main hopper, a main trough, a three-way diverted trough, a diverted string tube and a window inlet trough.

[0099] Lining casting adopts chute to cast layer by layer:

[0100] The lining casting adopts a chute to cast the lining layer by layer, and a lining trolley is used for the lining casting. A grading and diversion device is provided on the lining trolley. The grading and diversion device includes a multi-stage diversion component from top to bottom. Each multi-stage diversion component includes a main hopper 19, a main trough 20, a three-way diversion trough 21, a diversion string tube 22 and a window inlet trough 23.

[0101] By combining the hopper, main chute, "three-way" diverter trough, diverter string tube and window chute, and setting valves on the plug plates at each level, the concrete can flow to each working window, so as to realize the window-by-window feeding of the secondary lining arch wall concrete. Two main diverter hoppers are set at the center line of the top platform of the 12m trolley, and two first-level diverter troughs are set on the left and right sides of each main diverter funnel. The first and second-level diverter troughs are composed of arc chutes and first-level funnels. Eight diverter chutes are set on the left and right sides of the first-level funnel to lead to the corresponding working windows of the first and second-level platforms. The third-level diverter trough is composed of a string tube, a second-level funnel and an arc chute. The first-level funnel and the second-level funnel are connected by a string tube. Four diverter chutes are set on the left and right sides of the second-level funnel to the corresponding working windows of the third-level platform.

[0102] Specifically, the lining window casting setting method is:

[0103] When the concrete mixer truck delivers the concrete to the site, the concrete is pumped into the main hopper of the top platform by the concrete delivery pump. The concrete is poured in horizontal layers and symmetrically, and the pouring speed and the pouring height on one side are controlled. The pouring height on both sides should not exceed 0.5m. The vertical distance from the delivery hose outlet to the pouring surface should not exceed 2m, and the distance from the front and back of the trolley should not exceed 1m to prevent concrete segregation. The concrete is poured continuously, and the time interval between the pouring of two adjacent layers is controlled within 2h.

[0104] 4. Vibration with high and low frequency attached vibrators;

[0105] The vibration time of traditional attached vibrators is difficult to control, which can easily cause over-vibration and external defects such as "sand overflow". Traditional inserted vibrators are due to the large spacing between the concrete windows of the lining trolley, and the vibrator cannot fully cover them, which can easily cause missed vibrations. The side walls are prone to honeycombed surfaces, missing reinforcement and other quality defects, the vault is prone to hollowing out, and the concrete strength is difficult to meet the design requirements.

[0106] In order to overcome the above defects, in this embodiment, a vibrating rod is used in combination with high and low frequency attached vibrators to compact concrete. One trolley is equipped with 8 low-frequency vibrators (arranged on the side mold template, 8 high-frequency vibrators (arranged on the top mold template), totaling 16 units.

[0107] ① During the actual pouring process, the slump of concrete is controlled at 180mm, and symmetrical pouring and layered vibration are adopted.

[0108] ② The windows on the first, second and third floors are poured with chutes. When the concrete is poured to a position about 1m above the vibrator, the vibrator on that floor is started for 10 seconds at the same time. The attached vibrators on the second, third and arched floors are vibrated for 10 seconds at the same time. After demoulding for 12 hours, the surface flatness and finish of the entire concrete warehouse are good, and the 28-day strength is greater than the design value.

[0109] 5. Secondary lining maintenance

[0110] After demoulding, a movable fog cannon is used to spray and cure the lining concrete. The fog cannon device can be fixed on a sprinkler truck to achieve spray curing of concrete in each section of the tunnel or dust removal in the tunnel. During the curing period, the concrete surface must be kept moist, and the temperature of the curing water is basically the same as the ambient temperature. Spraying and curing is not allowed when the temperature is below 5℃.

[0111] When curing concrete with moisturizing film, if the concrete temperature is high before demolding, use water spraying at a temperature not lower than 20°C to cool the formwork. After demolding, a moisturizing film should be hung to cure the concrete surface.

[0112] Use the secondary lining trolley to lay and hang the moisturizing film. The curing is carried out in sections from top to bottom to prevent leakage of the moisturizing film. When the concrete is covered with plastic sheeting for curing, all exposed surfaces should be covered tightly.

[0113] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for rapid restoration of existing tunnel lining, characterized in that: The steps include: Step 1, the main tunnel operation section is divided into four sections: along the length direction of the main tunnel operation section, there are two sections: the second lining construction section, the first trestle section, the second trestle section and the expansion section, and the interval between adjacent sections is 20-50m; the tunnel invert construction process is carried out simultaneously in the first trestle section and the second trestle section; Step 2: Lay and hang waterproof panels on the entire tunnel section in the main tunnel operation section; Step 3: After the waterproof board is laid, the secondary lining reinforcement is constructed; first, the positioning reinforcement is constructed, the annular reinforcement and the longitudinal distribution reinforcement are installed according to the positioning reinforcement, and finally the connection reinforcement between the two layers of reinforcement is installed; Step 4: construct the longitudinal annular waterstop: including overlapping the longitudinal annular waterstop; Step 5: Casting and curing of secondary lining; the lining adopts hydraulic steel mold integral lining trolley, the secondary lining adopts large arc-shaped steel mold lining gantry, and the arch wall is molded in one step; Step 6: Repeat steps 1 to 5 to complete the restoration of all tunnel linings.

2. The method for rapid restoration of existing tunnel lining according to claim 1 is characterized in that: In step 1, a first transverse channel is provided at the front end of the main tunnel operation section, and a second transverse channel is provided at the rear end of the main tunnel operation section. The logistics transportation of the first pier area is carried out through the first transverse channel, and the logistics transportation of the second pier area is carried out through the second transverse channel.

3. The method for rapid restoration of existing tunnel lining according to claim 2 is characterized in that: The invert construction process of the first trestle area and the second trestle area is carried out simultaneously, and the logistics direction is opposite. The logistics conveying direction during the invert construction process of the expansion area is the same as that of the first trestle area.

4. The method for rapid restoration of existing tunnel lining according to claim 1 is characterized in that: After the waterproof board is installed, the arch formwork is installed, and the arch concrete is poured and maintained. After the arch construction is completed, the trestle is dismantled.

5. The method for rapid restoration of existing tunnel lining according to claim 1 is characterized in that: In step 4, the specific construction process of overlapping the longitudinal annular waterstop is as follows: S1. First, cut off the rubber of the lapped raised part of the steel edge rubber water stop; S2. Then put the steel plate waterstop and the steel edge rubber waterstop together, and anchor them with at least two rivets on each side; S3. After the rivets are anchored, the gap between the steel-edge rubber waterstop and the steel plate waterstop is tightly bonded with adhesive material.

6. The method for rapid restoration of existing tunnel lining according to claim 1 is characterized in that: In step 5, the lining pouring construction process is specifically as follows: firstly, the concrete surface is roughened, then the buffer cushion layer is constructed, and finally, the lining window is poured.

7. The method for rapid restoration of existing tunnel lining according to claim 6 is characterized in that: Before constructing the buffer layer, mark the center line of the bottom edge of the buffer layer, the center line of the annular hose and the center line of the drainage strip on the initial support surface. The bottom edge of the buffer layer is the rail top elevation. The annular hose and the annular drainage strip are arranged alternately. The buffer layer is laid between adjacent annular hoses. In the longitudinal and annular directions, multiple dovetail clamps are arranged between two adjacent buffer layers.

8. The method for rapid restoration of existing tunnel lining according to claim 7 is characterized in that: It is characterized in that The buffer layer is made of polyethylene.

9. The method for rapid restoration of existing tunnel lining according to claim 6 is characterized in that: The lining casting adopts a chute to cast the lining layer by layer, and a lining trolley is used for the lining casting. A grading and diversion device is provided on the lining trolley. The grading and diversion device includes multi-stage diversion components from top to bottom, and each multi-stage diversion component includes a main hopper, a main trough, a three-way diversion trough, a diversion string tube and a window inlet trough.

10. The method for rapid restoration of existing tunnel lining according to claim 9, characterized in that: The secondary lining casting is performed by symmetrically casting in layers from bottom to top in combination with layered vibration, and a low-frequency vibrator and a high-frequency vibrator are used in combination during the concrete consolidation process.

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