Rapid construction method for secondary lining molded concrete lining of large longitudinal slope tunnel

Abstract

The invention discloses a large longitudinal slope tunnel secondary lining molded concrete lining rapid construction method, and relates to the technical field of tunnel construction, and the method comprises the following steps: S1, primary support back flatness detection machine processing, and primary support inward laying of a composite waterproof layer, the composite waterproof layer sequentially comprises non-woven geotechnical cloth and a single-sided self-adhesive waterproof plate from the primary support to the inside; s2, after the waterproof layer is accepted and accepted, vault formwork grouting pipelines are laid on the surface of the waterproof plate in a clinging mode, the vault formwork grouting pipelines are arranged to be U-shaped pipelines including an exhaust pipe and a grouting pipe, and in secondary lining formwork concrete lining construction, a trackless stepping type hydraulic lining trolley is adopted, so that the defects that a large longitudinal slope trolley is difficult to position, and the construction efficiency is high are overcome; and the construction quality of the secondary lining molded concrete is ensured, the construction progress is accelerated, and the construction risks such as car running and mold running of the rail hydraulic trolley in the large longitudinal slope construction are avoided.

Description

Technical Field

[0001] The invention relates to the technical field of tunnel construction, in particular to a rapid construction method for secondary lining cast concrete lining of a tunnel with a large longitudinal slope. Background Art

[0002] In the construction of tunnels with large longitudinal slopes, due to the gravity of the trolley itself and the downward and horizontal forces during the concrete pouring process, the trolley may "slip" or "lift up", posing safety hazards. The traditional cast-in-place formwork support method has many construction processes, requires a lot of manpower, has a long construction period, and is costly. Traditional construction methods often require a lot of manpower to move and position the trolley and monitor the concrete pouring process. The use of a trackless step-by-step hydraulic lining trolley can reduce manpower input and improve construction efficiency.

[0003] In the prior art, in tunnels with large longitudinal slopes, track-type hydraulic trolleys rely on tracks for positioning and movement. Due to the existence of the large longitudinal slope, track laying becomes more difficult, and it is very difficult to ensure that the flatness and slope of the track meet the requirements. When the slope is large, the fixation of the track requires more supporting structures, and any slight deviation will lead to inaccurate positioning of the trolley. Summary of the invention

[0004] The object of the present invention is to provide a rapid construction method for secondary lining of cast-in-place concrete lining in a tunnel with a large longitudinal slope, so as to solve the above-mentioned problem of easy inaccurate positioning.

[0005] The present invention is achieved through the following technical solutions: A rapid construction method for secondary lining of cast concrete lining in a tunnel with a large longitudinal slope comprises the following steps: S1, the flatness detection machine is used to process the back of the initial support, and the composite waterproof layer is laid in sequence from the initial support to the inside. The composite waterproof layer is a non-interference geotextile and a single-sided self-adhesive waterproof board in sequence from the initial support to the inside; S2, after the waterproof layer is accepted, the vault molded grouting pipeline is laid close to the surface of the waterproof board. The vault molded grouting pipeline is arranged as a U-shaped pipeline, which is an exhaust pipe and a grouting pipe respectively. Branch grouting pipes are vertically arranged on both sides of the grouting pipe. Overflow holes are arranged at intervals of plum blossom shape on one side of the surface of the grouting pipe and the branch grouting pipe. A plum blossom-shaped exhaust hole is arranged on one side of the surface of the exhaust pipe. The grouting pipe, branch grouting pipe and exhaust hole are all tightly wrapped with PE film; S3, layout and design the center line, the trackless step-by-step lining trolley moves and positions, and the secondary lining mold-cast concrete is poured. The trackless step-by-step lining trolley is composed of a hydraulic cylinder master control center, a steel beam, a transverse support screw, a main beam, a bracket, a jacking cylinder, a vertical support leg, a guide column, a stepping mechanism and a transverse support bolted together; S4, vault grouting construction with formwork, including: S4-1, select grouting materials, S4-2, vault grouting construction with mold, S4-3, vault grouting effect inspection; S5, trackless stepping hydraulic trolley for demoulding.

[0006] Furthermore, in step S2, the exhaust pipe and the grouting pipe extend beyond the end of the lining trolley by a working length of 200 mm to 500 mm and are made of PVC pipes. The branch grouting pipe covers the surface of the exhaust pipe and is laid on the surface of the waterproof board.

[0007] Furthermore, in step S2, when the grouting pipe, branch grouting pipe and exhaust pipe are installed, the overflow hole and the exhaust hole are set close to the waterproof board and are adhered to the surface of the waterproof board with transparent tape. The exhaust pipe is located at the highest point of the second lining arch when buried.

[0008] Furthermore, in step S3, the lateral supporting screws are provided in multiple groups and are evenly distributed on both sides of the trolley, one side is connected to the trolley panel, and the other side is connected to the trolley steel beam.

[0009] Furthermore, in step S3, the bull legs, lifting cylinders, vertical legs, guide columns and transverse supports are provided in four groups and are symmetrically arranged on the left and right sides of the trolley.

[0010] Furthermore, in step S3, the stepping mechanism includes four groups of supports, a longitudinal travel cylinder and a support connecting rod, and the four groups of supports are symmetrically arranged on the left and right sides of the trolley.

[0011] Furthermore, in step S3, two main beams are provided, and the two main beams are both provided at the bottom ends of both sides of the trolley, and slide grooves are provided on the two main beams, the top of the lifting cylinder is connected with the corbel bolts, the bottom of the lifting cylinder is connected with the top bolts of the guide column, the guide column passes through the top of the main beam and is connected with the bottom bolts of the lifting cylinder, and the bottom of the guide column is embedded in the slideway of the transverse support, and the two supports on the same side of the stepping mechanism are fixed to the main beam through the slideway, and the supports on the left and right sides are connected through the support connecting rods, one end of the longitudinal walking cylinder in the stepping mechanism is bolted to the main beam, and the other end is bolted to the support, and a transverse cylinder is provided on the transverse support, one end of the transverse cylinder is bolted to the guide column, and the other end is bolted to the transverse support.

[0012] Furthermore, step S3 also includes a trolley walking and positioning step, and the trolley walking and positioning step is: S31-1, synchronously retract the strokes of the four lifting cylinders, and the four guide columns drive the four lateral supports to lift and leave the ground, while the two main beams on both sides and the four supports at the bottom fall to the ground; S31-2, start the hydraulic cylinder master control center, the longitudinal travel cylinder extends, the trolley moves longitudinally along the slideway, and one stroke is completed; S31-3, the four lifting cylinders are extended synchronously, and the four guide columns drive the four lateral supports to descend and close to the ground. At the same time, the four supports at the bottom of the two main beams on both sides fall to the ground and leave the ground; S31-4, start the hydraulic cylinder master control center, shrink the longitudinal travel cylinder to zero, drive the two supports on both sides to move forward one stroke, and repeat the steps S31-1 to S31-4 to make the trolley step to the designed position; S31-5: Start the four transverse cylinders on the four transverse supports to realize the left and right movement of the trolley, so that the axis of the trolley coincides with the design axis. When adjusting to the left, the stroke of the left transverse cylinder shrinks and the stroke of the right transverse cylinder extends. When adjusting to the right, the stroke of the left transverse cylinder extends and the stroke of the right transverse cylinder shrinks.

[0013] Furthermore, in step S4-1, the grouting material includes cement-based, water glass-based and composite polymer-based materials; In step S4-2, the grouting time is after the secondary lining formwork concrete pouring is completed, and the grouting can be implemented. The grouting stop valve is connected to the exposed working length of the exhaust pipe, and a pressure needle is set on the grouting stop valve. Before the vault formwork grouting, it should be determined through tests to break through the PE film covering the overflow hole and the exhaust hole. During the grouting process, the grouting pipeline is connected, the grouting stop valve at the end of the exhaust hole is closed, and the grouting is continuously pressurized. When the initial test pressure is reached, the slurry breaks through the PE film through the overflow hole, allowing the slurry to enter the cavity. When the cavity is gradually filled with slurry, the air pressure in the pipeline increases, and breaks through the PE film covering the exhaust hole, the exhaust hole is exhausted, and the slurry fills the cavity; During the grouting process, continuously observe the changes in the pressure gauge. When the pressure is about to reach the initial pressure, open the stop valve and exhaust the gas in time. During the grouting process, increase the pressure by 0.1MPa every 2 hours. When the exhaust hole discharges the grouting slurry with the same ratio, close the stop valve and maintain the pressure stable for 2 hours. After the grouting of the arch form is completed, use high-strength mortar to seal the overflow hole and the exhaust hole.

[0014] Furthermore, in step S4-3, the effect of the grouting of the vault with the mold is detected by using geological radar; In step S5, the above steps S1 to S5 are repeated to complete the secondary lining cast-in-place concrete construction of the large longitudinal slope tunnel.

[0015] Compared with the prior art, the present invention has the following advantages and beneficial effects: 1. The present invention adopts a trackless step-by-step hydraulic lining trolley, and realizes longitudinal forward movement of the trolley through the jacking cylinder and the hydraulic stepping mechanism, and easily realizes left and right movement and positioning of the trolley through four transverse cylinders on four transverse supports. It has a high degree of mechanization and saves labor. It successfully overcomes the technical problems that the tracked hydraulic trolley is difficult to position on a large longitudinal slope, there are great safety risks in walking, and after the lining trolley is positioned, it is easy to run out of the mold and cause quality accidents during the pouring of concrete; 2. The present invention uses a vault grouting construction technology with a mold, which is simple to operate, reliable, and has low technical requirements for workers. Grouting pipes can be made locally and are inexpensive. It successfully solves the problem of loose vault pouring and vault cavities during the top-punching process of the second lining mold concrete on a large longitudinal slope, making the second lining mold concrete more closely connected with the initial support, thereby increasing the integrity of the entire tunnel structure; 3. In the present invention, a sensing device is installed at the bottom of each pouring window. An intelligent means is adopted to set the sensing device at the bottom of the pouring window, so that manual monitoring of the concrete pouring height during the concrete pouring process is avoided, and a large amount of labor is saved. A PVC grouting pipe is installed on the top of the waterproof board. When the secondary lining cast concrete is poured for about 3 hours, the grouting pipe is connected to implement the vault mold grouting, which effectively fills the loose vault parts that are prone to appear in the reverse slope concrete pouring during the secondary lining cast concrete construction, thereby improving the integrity of the tunnel lining structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings: Figure 1 is a flow chart of the method steps of the present invention; Figure 2 It is a front view of the overall structure of the present invention; Figure 3 for Figure 2 Middle AA section; Figure 4 for Figure 2 Middle A section detail drawing; Figure 5 This is a cross-sectional view of the slide.

[0017] The reference numerals represent: 1-hydraulic cylinder master control center, 2-steel beam, 3-lateral support screw, 4-main beam, 5-corbel, 6-lifting cylinder, 7-vertical support leg, 8-guide column, 9-support connecting rod, 10-longitudinal walking cylinder, 11-support, 12-lateral support, 13-lateral cylinder, 14-composite waterproof layer, 15-secondary lining cast concrete, 16-cavity, 17-exhaust pipe, 18-grouting pipe, 19-U-shaped pipe, 20-overflow hole, 21-exhaust hole, 22-stop valve, 23-grouting pipeline, 24-branch grouting pipe, 25-casting window, 26-sensing device, 27-slide. DETAILED DESCRIPTION

[0018] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0019] like Figures 1 to 5 As shown, the present invention comprises the following steps: S1, the flatness detection machine is used behind the initial support, and the composite waterproof layer 14 is laid in sequence from the initial support to the inside. The composite waterproof layer 14 is sequentially laid from the initial support to the inside, including non-interference geotextile and single-sided self-adhesive waterproof board.

[0020] S2, after the waterproof layer is accepted, the vault molded grouting pipeline 23 is laid close to the surface of the waterproof board. The vault molded grouting pipe 23 is arranged as a U-shaped pipeline, which are respectively an exhaust pipe 17 and a grouting pipe 18. The exhaust pipe 17 and the grouting pipe 18 extend beyond the end of the lining trolley by 200mm to 500mm of working length and are made of PVC pipes. The branch grouting pipe 24 covers the surface of the exhaust pipe 17 and is laid on the surface of the waterproof board. The exhaust pipe 17 and the grouting pipe 18 are both straight PVC pipes. The tails of the two pipes are connected into a U shape by a U-shaped pipe 19. Branch grouting pipes 24 are vertically arranged on both sides of the grouting pipe 18. Overflow holes 20 are arranged at intervals of plum blossom shape on one side of the surface of the grouting pipe 18 and the branch grouting pipe 24. A plum blossom-shaped exhaust hole 21 is arranged on one side of the surface of the exhaust pipe 17. The grouting pipe 18, the branch grouting pipe 24 and the exhaust hole 21 are all tightly wrapped with PE film. The PE film The starting and ending positions are firmly adhered with double-sided tape or transparent tape, and the tape must not be pasted to block the overflow hole 20 and the exhaust hole 21. The PE film winding standard is: during the pouring of the secondary lining formwork concrete 15, the PE film is not damaged to prevent the concrete slurry from entering the grouting pipe 18, the branch grouting pipe 24 and the exhaust hole 21 to block the pipeline. At the same time, it is ensured that the grouting pressure during the grouting process can break through the PE film to ensure that the cavity 16 is filled densely. When installing the grouting pipe 18, the branch grouting pipe 24 and the exhaust pipe 17, the overflow hole 20 and the exhaust hole 21 are set close to the waterproof board and are adhered to the surface of the waterproof board with transparent tape. The exhaust pipe 17 is located at the highest point of the second lining arch when buried. In order to prevent the pre-buried pipeline from being offset and ensure that its linear shape meets the requirements, a full-length positioning steel bar can be set during the construction process to fix the pipeline and fix it on the main reinforcement of the secondary lining.

[0021] S3, layout and design center line, trackless step-type lining trolley walking and positioning, and pouring of secondary lining molded concrete 15, the trackless step-type lining trolley is composed of a hydraulic cylinder master control center 1, a steel beam 2, a transverse support screw 3, a main beam 4, a bracket 5, a jacking cylinder 6, a vertical support leg 7, a guide column 8, a stepping mechanism and a transverse support 12 bolted together, and the above components are connected to each other as a whole by bolting, the number of cylinder master control centers matches the number of trolley hydraulic systems, and are connected by hydraulic pipelines; There are multiple groups of transverse support screws 3 evenly distributed on both sides of the trolley, one side is connected to the trolley panel, and the other side is connected to the trolley steel beam 2. When the trolley is moved longitudinally or transversely into place, the screws are retracted or extended and fixed so that the trolley panel is on the designed arc surface; Four groups of brackets 5, lifting cylinders 6, vertical legs 7, guide columns 8 and transverse supports 12 are arranged symmetrically on the left and right sides of the trolley. The four lifting cylinders 6 are raised and lowered at the same time to realize the lifting and lowering of the trolley. The four vertical legs 7 are located at the four ends of the main beam 4. They are adjusted up and down by rotation to be close to the ground during the pouring of concrete, which has the function of preventing overturning. The stepping mechanism includes four groups of supports 11, longitudinal travel cylinders 10 and support connecting rods 9. The four groups of supports 11 are symmetrically arranged on the left and right sides of the trolley. There are two main beams 4, both of which are arranged at the bottom ends of both sides of the trolley. Slideways are arranged on the two main beams 4. The top of the jacking cylinder 6 is bolted to the bull leg 5, and the bottom of the jacking cylinder 6 is bolted to the top of the guide column 8. The guide column 8 passes through the top of the main beam 4 and is bolted to the bottom of the jacking cylinder 6. The bottom of the guide column 8 is embedded in the slideway 27 of the transverse support 12. The two supports 11 on the same side of the stepping mechanism are fixed to the main beam 4 through the slideway 27. The supports on the left and right sides are fixed to the main beam 4 through the slideway 27. 11 are connected through the support connecting rod 9, one end of the longitudinal travel cylinder 10 in the stepping mechanism is bolted to the main beam 4, and the other end is bolted to the support 11, and a transverse cylinder 13 is provided on the transverse support 12, one end of the transverse cylinder 13 is bolted to the guide column 8, and the other end is bolted to the transverse support 12. Starting the transverse cylinder 13 can realize the left or right translation of the trolley, and the transverse cylinder 13 is extended and retracted, so that the guide column 8 moves left and right along the slide 27, realizing the left and right translation of the trolley; The steps for trolley travel positioning are: S31-1, the four lifting cylinders 6 are retracted synchronously, and the four guide columns 8 drive the four lateral supports 12 to lift and leave the ground, while the two main beams 4 on both sides and the four supports 11 at the bottom fall to the ground; S31-2, start the hydraulic cylinder master control center 1, the longitudinal travel cylinder 10 extends, the trolley moves longitudinally along the slideway 27, and one stroke is completed; S31-3, the four lifting cylinders 6 are extended synchronously, and the four guide columns 8 drive the four lateral supports 12 to descend and close to the ground, and at the same time, the four supports 11 at the bottom of the two main beams 4 on both sides fall to the ground and leave the ground; S31-4, start the hydraulic cylinder master control center 1, the longitudinal travel cylinder 10 shrinks to zero, drives the two supports 11 on both sides to move forward a stroke, and repeats the steps S31-1 to S31-4 to make the trolley step to the designed position; S31-5: Start the four transverse cylinders 13 on the four transverse supports 12 to realize the left and right movement of the trolley, so that the axis of the trolley coincides with the design axis. When adjusting to the left, the stroke of the left transverse cylinder 13 is contracted, and the stroke of the right transverse cylinder 13 is extended. When adjusting to the right, the stroke of the left transverse cylinder 13 is extended, and the stroke of the right transverse cylinder 13 is contracted; The pouring of the secondary lining cast concrete 15 comprises the following steps: Several opening and closing pouring windows 25 are evenly arranged at equal intervals on the panel of the trackless step-by-step hydraulic trolley. The arch is designed with a longitudinally movable distributor. During the concrete pouring process, the concrete can be poured into the mold window by window, eliminating the "herringbone slope" in the traditional concrete pouring process. Several sensing devices 26 are correspondingly arranged under the several pouring windows 25. When the concrete pouring is a certain distance away from the bottom of the pouring window 25, an alarm signal is issued to proceed to the next window pouring.

[0022] S4, vault grouting construction with formwork, including: S4-1, select grouting materials with micro-expansion to effectively ensure the density of grouting of cavity 16. Grouting materials include cement-based, water glass-based and composite polymer-based materials. Grouting materials are available for use at any time. S4-2, vault grouting construction with formwork: Grouting can be carried out after the secondary lining cast concrete 15 is poured. A stop valve 22 is connected to the exposed working length of the exhaust pipe 17, and a pressure needle is set on the stop valve 22. Before grouting the vault with the mold, it should be determined through tests to break through the PE film covering the overflow hole 20 and the exhaust hole 21. During the grouting process, the grouting pipeline 23 is connected, the stop valve 22 at the end of the exhaust hole 21 is closed, and the grouting is continuously pressurized. When the initial test pressure is reached, the slurry breaks through the PE film through the overflow hole 20, so that the slurry enters the cavity 16. When the cavity 16 is gradually filled with the slurry, the air pressure in the pipeline increases and breaks through the PE film covering the exhaust hole 21, the exhaust hole 21 is exhausted, and the slurry fills the cavity 16. During the grouting process, the pressure gauge changes are continuously observed. When the pressure is about to reach the initial pressure, the stop valve 22 is opened to exhaust in time. During the grouting process, the pressure is increased by 0.1 MPa every 2 hours. When the exhaust hole 21 discharges the grouting slurry with the same ratio, the stop valve 22 is closed and the pressure is maintained for 2 hours. After the vault grouting is completed, the overflow hole 20 and the exhaust hole 21 are sealed with high-strength mortar; S4-3, detection of the effect of grouting with mold on the vault, detection by geological radar.

[0023] S5, demoulding by trackless step-by-step hydraulic trolley, repeating the above steps S1 to S5 to complete the construction of secondary lining cast concrete 15 of the steep longitudinal slope tunnel.

[0024] In summary, in the construction of the secondary lining cast concrete lining, a trackless step-by-step hydraulic lining trolley is used to overcome technical difficulties such as the difficulty in positioning the trolley on a large longitudinal slope and the safety risks in walking, thereby ensuring the construction quality of the secondary lining cast concrete and speeding up the construction progress, and avoiding the construction risks of the tracked hydraulic trolley running away or running away during construction on a large longitudinal slope.

[0025] A PVC grouting pipe 18 is installed on the top of the waterproof board. About 3 hours after the secondary lining cast concrete is poured, the grouting pipe 23 is connected to implement the arch mold grouting, which effectively fills the loose parts of the arch that are prone to occur during the reverse slope concrete pouring during the secondary lining cast concrete construction, thereby improving the integrity of the tunnel lining structure.

[0026] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A rapid construction method for secondary lining of cast concrete lining in a tunnel with a large longitudinal slope, characterized in that The following steps are involved: S1, the flatness detection machine is used to process the back of the initial support, and a composite waterproof layer (14) is laid in sequence from the initial support to the inside, wherein the composite waterproof layer (14) is a non-interference geotextile and a single-sided self-adhesive waterproof board in sequence from the initial support to the inside; S2, after the waterproof layer is accepted, a vault molded grouting pipe (23) is laid close to the surface of the waterproof board, the vault molded grouting pipe (23) is arranged as a U-shaped pipe, which includes an exhaust pipe (17) and a grouting pipe (18), and branch grouting pipes (24) are vertically arranged on both sides of the grouting pipe (18), and overflow holes (20) are arranged in a plum blossom shape on one side of the surface of the grouting pipe (18) and the branch grouting pipe (24), and a plum blossom-shaped exhaust hole (21) is arranged on one side of the surface of the exhaust pipe (17), and the grouting pipe (18), the branch grouting pipe (24) and the exhaust hole (21) are all tightly wrapped with a PE film; S3, laying out the design center line, positioning the trackless step-by-step lining trolley, and pouring the secondary lining molded concrete (15), wherein the trackless step-by-step lining trolley is composed of a hydraulic cylinder master control center (1), a steel beam (2), a transverse support screw (3), a main beam (4), a bracket (5), a jacking cylinder (6), a vertical support leg (7), a guide column (8), a stepping mechanism and a transverse support (12) bolted together; S4, vault grouting construction with formwork, including: S4-1, select grouting materials, S4-2, vault grouting construction with mold, S4-3, vault grouting effect inspection; S5, trackless stepping hydraulic trolley for demoulding.

2. The rapid construction method for secondary cast concrete lining of a steep longitudinal slope tunnel according to claim 1 is characterized by: In step S2, the exhaust pipe (17) and the grouting pipe (18) extend beyond the end of the lining trolley by a working length of 200 mm to 500 mm and are made of PVC pipes. The branch grouting pipe (24) covers the surface of the exhaust pipe (17) and is laid on the surface of the waterproof board.

3. The rapid construction method for secondary cast concrete lining of a steep longitudinal slope tunnel according to claim 2 is characterized by: In step S2, when the grouting pipe (18), the branch grouting pipe (24) and the exhaust pipe (17) are installed, the overflow hole (20) and the exhaust hole (21) are arranged close to the waterproof board and are adhered to the surface of the waterproof board using transparent tape, and the exhaust pipe (17) is located at the highest point of the second lining arch when buried.

4. The rapid construction method for secondary cast concrete lining of a steep longitudinal slope tunnel according to claim 3 is characterized by: In step S3, the lateral support screws (3) are provided in multiple groups and are evenly distributed on both sides of the trolley, one side is connected to the trolley panel, and the other side is connected to the trolley steel beam (2).

5. The rapid construction method for secondary cast concrete lining of a steep longitudinal slope tunnel according to claim 4 is characterized by: In step S3, the brackets (5), the lifting cylinders (6), the vertical legs (7), the guide columns (8) and the transverse supports (12) are provided in four groups and are symmetrically arranged on the left and right sides of the trolley.

6. A rapid construction method for secondary cast concrete lining of a steep longitudinal slope tunnel according to claim 5, characterized in that: In step S3, the stepping mechanism comprises four groups of supports (11), a longitudinal travel cylinder (10) and a support connecting rod (9), and the four groups of supports (11) are symmetrically arranged on the left and right sides of the trolley.

7. A rapid construction method for secondary cast concrete lining of a steep longitudinal slope tunnel according to claim 6, characterized in that: In step S3, two main beams (4) are provided, and the two main beams (4) are both provided at the bottom ends of both sides of the trolley. Slide grooves are provided on the two main beams (4). The top of the lifting cylinder (6) is bolted to the bracket (5), and the bottom of the lifting cylinder (6) is bolted to the top of the guide column (8). The guide column (8) passes through the top of the main beam (4) and is bolted to the bottom of the lifting cylinder (6). The bottom of the guide column (8) is embedded in the slideway (27) of the transverse support (12). The two supports (11) on the same side of the stepping mechanism are fixed to the main beam (4) through a slideway (27), and the supports (11) on the left and right sides are connected through a support connecting rod (9). One end of the longitudinal travel cylinder (10) in the stepping mechanism is bolted to the main beam (4), and the other end is bolted to the support (11). A transverse cylinder (13) is arranged on the transverse support (12), and one end of the transverse cylinder (13) is bolted to the guide column (8), and the other end is bolted to the transverse support (12).

8. The rapid construction method for secondary cast concrete lining of a steep longitudinal slope tunnel according to claim 7 is characterized by: Step S3 also includes a trolley walking and positioning step, which is as follows: S31-1, synchronously retract the stroke of the four lifting cylinders (6), and the four guide columns (8) drive the four transverse supports (12) to be lifted and leave the ground, while the two main beams (4) on both sides and the four supports (11) at the bottom fall to the ground and contact the ground; S31-2, the hydraulic cylinder master control center (1) is started, the longitudinal travel cylinder (10) is extended, and the trolley moves longitudinally along the slideway (27), and one stroke is completed; S31-3, the four lifting cylinders (6) are extended synchronously, and the four guide columns (8) drive the four transverse supports (12) to descend and close to the ground, and at the same time, the four supports (11) at the bottom of the two main beams (4) on both sides fall to the ground and leave the ground; S31-4, start the hydraulic cylinder master control center (1), shrink the longitudinal travel cylinder (10) to zero, drive the two supports (11) on both sides to move forward a stroke, and repeat the steps S31-1 to S31-4 to make the trolley step to the designed position; S31-5: Start the four transverse cylinders (13) on the four transverse supports (12) to achieve left and right movement of the trolley so that the axis of the trolley coincides with the design axis. When adjusting to the left, the stroke of the left transverse cylinder (13) is contracted and the stroke of the right transverse cylinder (13) is extended. When adjusting to the right, the stroke of the left transverse cylinder (13) is extended and the stroke of the right transverse cylinder (13) is contracted.

9. A rapid construction method for secondary cast concrete lining of a steep longitudinal slope tunnel according to claim 8, characterized in that: In step S4-1, the grouting materials include cement-based, water glass-based and composite polymer-based materials; In step S4-2, the grouting time is after the pouring of the secondary lining cast concrete (15) is completed. The grouting can be carried out only after the exposed working length of the exhaust pipe (17) is connected. At the same time, a pressure needle is set on the grouting stop valve (22). Before the arch top is grouted with the mold, it should be determined through experiments that the PE film covering the overflow hole (20) and the exhaust hole (21) is broken. During the grouting process, the grouting pipeline (23) is connected, the grouting stop valve (22) at the end of the exhaust hole (21) is closed, and the grouting is continuously pressurized. When the initial test pressure is reached, the grout breaks through the PE film through the overflow hole (20), so that the grout enters the cavity (16). When the cavity (16) is gradually filled with the grout, the air pressure in the pipeline increases and breaks through the PE film covering the exhaust hole (21). The exhaust hole (21) is exhausted and the grout fills the cavity (16). During the grouting process, the pressure gauge is continuously monitored. When the pressure is about to reach the initial pressure, the stop valve (22) is opened to exhaust the gas in time. During the grouting process, the pressure is increased by 0.1 MPa every 2 hours. When the exhaust hole (21) discharges the grouting slurry with the same proportion, the stop valve (22) is closed and the pressure is maintained at a constant level for 2 hours. After the grouting of the vault with the mold is completed, the overflow hole (20) and the exhaust hole (21) are sealed with high-strength mortar.

10. A rapid construction method for secondary cast concrete lining of a steep longitudinal slope tunnel according to claim 9, characterized in that: In step S4-3, the effect of grouting with a mold on the vault is tested by geological radar; In step S5, the above steps S1 to S5 are repeated to complete the construction of the secondary lining cast concrete (15) of the steep longitudinal slope tunnel.

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