Weak surrounding rock tunnel advance support and construction method thereof

Abstract

The invention discloses a weak surrounding rock tunnel advance support and a construction method thereof, the weak surrounding rock tunnel advance support comprises a pipe shed support and a tunnel portal template support, and a tunnel template comprises a built-in corrugated plate, an assembly inverted arch bottom plate and a lower corner template; the built-in corrugated plate consists of a corrugated plate with built-in reinforcing ribs and a steel grid; the corrugated plate with the built-in reinforcing ribs is firstly prefabricated, and the corrugated plate with the built-in reinforcing ribs and the steel grids are spliced and connected on site to form the built-in corrugated plate; the assembled inverted arch bottom plate is a prefabricated laminated bottom plate and is of a prefabricated reinforced concrete structure. The method is high in adaptability, construction procedures are reduced, engineering measure cost is reduced, and installation efficiency and precision are ensured.

Description

Technical Field

[0001] The invention relates to the technical field of formwork, and in particular to an advance support for a soft surrounding rock tunnel and a construction method thereof. Background Art

[0002] The technology of assembled integral concrete pipe gallery is in line with the development of building industrialization and is constantly developing and improving. The technology of assembled integral concrete pipe gallery realizes the construction method of "factory processing of components and on-site assembly of structures". By splitting into prefabricated components such as prefabricated bottom plates, prefabricated top plates, and prefabricated wall panels, it avoids the problems of heavy prefabricated pipe gallery components and inconvenient assembly. At the same time, it solves the problem of node waterproofing, greatly improves the construction quality and efficiency, and realizes green and energy-saving construction. With the above characteristics, the technology of assembled integral concrete pipe gallery solves the problems of construction quality and efficiency of comprehensive pipe gallery, and helps the construction of national comprehensive pipe gallery.

[0003] At present, during the construction and installation of the prefabricated concrete pipe gallery, a large number of vertical supports need to be arranged when installing the prefabricated top plate of the pipe gallery, and inclined supports are used when installing the prefabricated wall panels of the pipe gallery. The vertical supports and inclined supports are intertwined, which makes the space for construction workers to work in the pipe gallery relatively narrow, affecting the construction progress and not conducive to timely escape in emergencies, posing a more prominent safety hazard. When the existing trolley is used to construct the lining, it is necessary to wait for the final setting of the previous lining before proceeding to the next working condition, or only prefabricated construction can be used. However, the prefabricated type has high requirements for industrialization and is difficult to implement in places with unfavorable traffic such as mountainous areas. Therefore, it is necessary to solve the problems of continuity and efficiency of construction conditions. Summary of the invention

[0004] The present invention provides a construction method of an assembled corrugated plate tunnel formwork, which is implemented by the following technical solutions:

[0005] A kind of advance support for a soft surrounding rock tunnel, including pipe-roof support and tunnel mouth template support, wherein the pipe-roof support includes a steel arch and a grouting pipe, the curvature of the steel arch is the same as that of the tunnel mouth, the steel arch is arranged at the tunnel mouth, a fixed ring is arranged on the steel arch, the grouting pipe is penetrated on the fixed ring and penetrated into the soil at the upper part of the tunnel mouth, the penetration of the grouting pipe is arranged to be inclined upward, wherein the tunnel mouth template support is arranged at a pre-excavated tunnel, the tunnel mouth template support includes an internal corrugated plate, an externally detachable corrugated plate, and an assembled inverted arch bottom plate; it is characterized in that: the internal corrugated plate is composed of an internal corrugated plate and reinforcing ribs, wherein the reinforcing ribs are penetrated in holes arranged between the crests and troughs of the internal corrugated plate, and the internal corrugated plate is close to and fully distributed on the inner wall of the tunnel; the bottom of the internal corrugated plate and the assembled inverted arch bottom plate The assembled inverted arch bottom plate is a prefabricated composite bottom plate and a prefabricated reinforced concrete structure. The side surfaces of the two ends of the assembled inverted arch bottom plate are fitted with the arc surface of the tunnel bottom, and the cross-section of the assembled inverted arch bottom plate is a shape of larger upper part and smaller lower part; the upper surfaces of the two ends of the assembled inverted arch bottom plate are both provided with a first mounting groove and a second mounting groove, the first mounting groove and the second mounting groove are extended and arranged in parallel along the length direction of the assembled inverted arch bottom plate, and the spacing is set equal to the thickness of the secondary lining, and the built-in corrugated plate is installed in the first mounting groove; the gap between the built-in corrugated plate and the inner wall of the tunnel is filled with high-strength concrete as the initial support of the tunnel, and the externally dismantled corrugated plate is installed after the concrete solidifies; the externally dismantled corrugated plate is installed in the second mounting groove, and cast-in-place reinforced concrete is filled between the externally dismantled corrugated plate and the built-in corrugated plate as the secondary lining.

[0006] An end template is set at the end face of the externally dismantled corrugated plate, a secondary lining steel cage structure is arranged between the externally dismantled corrugated plate and the internally dismantled corrugated plate, and the steel cage structure and the externally dismantled corrugated plate are installed by a secondary lining trolley.

[0007] The first installation groove is a U-shaped groove with the groove facing upward. The first installation groove is installed on the assembly arch bottom plate through bolt embedded parts. An internal corrugated plate is installed in the first installation groove, and a waterproof sealing material is filled in the gap between the side wall of the first installation groove and the internal corrugated plate.

[0008] The first installation groove and the second installation groove are both arranged continuously throughout the length. The reinforcing ribs passing through the built-in corrugated plate are post-tensioned prestressed ribs. Anchor seats are arranged in the two rows of first installation grooves at both ends of the assembled arch bottom plate for anchoring the post-tensioned prestressed ribs. When the strength of the high-strength concrete filled between the built-in corrugated plate and the inner wall of the tunnel reaches 75%, the prestressed ribs are tensioned.

[0009] During construction, pipe shed support is constructed according to the setting requirements. The tunnel entrance is excavated first to form the construction face. A steel arch is installed at the corresponding tunnel entrance. The steel arch is close to the inside of the tunnel entrance. Then, holes are drilled on the working surface to be excavated. A fixed ring is installed on the steel arch at the corresponding drilling position. The grouting pipe is inserted on the fixed ring and penetrated into the soil above the tunnel entrance. The grouting pipe is inserted in an inclined upward direction. After the grouting pipe is installed, grouting construction is carried out after passing the inspection.

[0010] After that, the tunnel mouth formwork support formwork construction is carried out. First, the internal corrugated plate and the externally dismantled corrugated plate are made. The internal corrugated plate is provided with a reinforcement hole. According to the support order of the tunnel, the prefabricated components are placed and connected, and the first installation groove and the second installation groove are installed. The lining trolley enters the tunnel for preliminary support construction, and the internal corrugated plate is fixedly installed and filled with high-strength concrete. The prestressed reinforcement bars are subsequently tensioned. After the final setting, the lining trolley performs the secondary lining construction, and the secondary lining reinforced concrete steel cage is installed and the externally dismantled corrugated plate is installed, and concrete is poured. When the lining trolley performs the secondary lining construction, the secondary lining construction is segmented. After the secondary lining is poured, it immediately moves forward to the next lining condition without waiting for the final setting of the secondary lining. The removable corrugated plate can be removed and reused after the final setting of the previous lining structure. The construction steps of the tunnel mouth formwork support are as follows:

[0011] S1: Make internal corrugated panels and external corrugated panels;

[0012] Using engineering drawings, calculate tunnel section parameters and determine the shape and size of the support; based on the shape and size, use hydraulic forming machinery to prefabricate corrugated plates, with holes reserved on the built-in corrugated plates to fix the reinforcing ribs; remove dirt from the surface of the corrugated plates; make them on a brushing machine and a rubbing machine, using the axial movement of the upper group of grinding rollers to brush on the metal surface to obtain wavy patterns, with grouting holes reserved on both the built-in corrugated plates and the external corrugated plates;

[0013] S2: placement and connection of prefabricated components;

[0014] The assembly inverted arch bottom plate is installed and placed at the bottom of the tunnel, the assembly inverted arch bottom plates are connected by force transmission rods, and the gaps therebetween are sealed with waterproof materials; the first installation groove and the second installation groove are installed on the assembly inverted arch bottom plate;

[0015] The laying and assembly of the inverted arch bottom plate is carried out in sections of 50m each. The internal corrugated plates are laid along the tunnel section. Two adjacent corrugated plates along the tunnel depth direction are connected by bolts. After the installation and connection of the components are completed, concrete is filled into the grouting holes of the corrugated plate wall. When the strength of the high-strength concrete filled between the internal corrugated plate and the inner wall of the tunnel reaches 75%, the prestressed tendons are tensioned. Subsequently, the gap between the first installation groove and the internal corrugated plate is sealed with waterproof sealing materials.

[0016] S3: Secondary lining pouring;

[0017] A steel cage is constructed outside the built-in corrugated plate by a lining trolley, which is arranged on one side of the steel cage and welded to the surface of the built-in corrugated plate by spot welding. The externally dismantled corrugated plate is installed in the second installation groove, and the externally dismantled corrugated plate is close to the outside of the steel cage. The two bottom lower ends of the externally dismantled corrugated plate are connected to the side plate of the second installation groove by bolts. The end formwork is then constructed for closed pouring, and then concrete is poured as a secondary lining;

[0018] S4: Continuous construction of lining trolley

[0019] After the secondary lining is poured, it will immediately move forward to the next lining condition without waiting for the final setting of the secondary lining. After the secondary lining construction of the previous condition is completed, the lining trolley will immediately move to the next condition for continuous construction. After the secondary lining of the previous condition is finally set, the external formwork and end formwork will be removed for the next condition construction, thereby realizing the continuous construction of the tunnel lining.

[0020] A waterproof structure is arranged between the two built-in corrugated plates, and the waterproof structure is composed of waterproof coiled material, filling material, embedded water stop strip and sealant.

[0021] In step S2, the assembled arch bottom plate is laid on the fine mortar layer, and waterproof materials are arranged at the joints of the assembled arch bottom plate. The waterproof structure is composed of waterproof membrane, filling materials, waterstop and sealant; wherein the waterstop is horizontally symmetrically buried in the upper part of the assembled arch bottom plate at both ends, the deformation joint is filled with filling materials, and the upper part of the deformation joint is sealed.

[0022] The beneficial effects of the present invention are as follows:

[0023] The tunnel opening formwork support of the present application not only realizes the pre-stressing requirements before excavation, but also the formwork structure therein can constitute an integrated support structure for the main tunnel excavation;

[0024] In view of the limitations of existing tunnel formwork construction, the present invention has strong adaptability, reduces construction procedures, reduces engineering measures costs, and ensures installation efficiency and accuracy.

[0025] The tunnel support structure is constructed as a whole, combining the primary lining with the secondary lining. There is no need to wait for the final setting of the previous working condition. The trolley can be moved immediately after the external corrugated plate is installed and the concrete is poured, so continuous construction can be carried out.

[0026] The first preliminary support structure is formed by combining the shape characteristics of the built-in corrugated plate with the post-tensioned reinforcement ribs. The secondary lining is constructed by using the formwork of the externally dismantled corrugated plate. The externally dismantled corrugated plate is made of aluminum alloy, which can play a waterproof role. The prefabricated components are easy to transport and can be mass-produced and applied. In environments with harsh hydrogeological conditions, the corrugated plate can effectively protect the steel bars and concrete and extend their service life. The construction process is mainly based on assembly, which speeds up the construction process and reduces the construction period. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0028] Figure 1 It is a schematic cross-sectional diagram of the pipe shed support of the present invention;

[0029] Figure 2 It is a schematic cross-sectional diagram of the pipe shed support of the present invention;

[0030] Figure 3 It is a schematic diagram of the tensioning of the reinforcing ribs of the present invention;

[0031] Figure 4 This is a schematic diagram of the connection of the reinforcing ribs of the present invention;

[0032] Figure 5 This is a schematic diagram of the tunnel mouth formwork support sequence of the present invention;

[0033] In the figure: 1. Internal corrugated plate; 2. Externally disassembled corrugated plate; 3. Assembled arch bottom plate; 4. First mounting groove; 5. Second mounting groove; 6. Anchor seat; 7. Reinforcement ribs; 11. Steel arch; 12. Grouting pipe; 13. Fixed ring. DETAILED DESCRIPTION

[0034] The following description of the embodiments will help the public better understand the present invention, but the specific embodiments given by the applicant cannot and should not be regarded as limitations on the technical solutions of the present invention. Any changes to the definitions of components or technical features and / or formal but not substantial changes to the overall structure should be regarded as the scope of protection defined by the technical solutions of the present invention.

[0035] Embodiment 1:

[0036] A soft surrounding rock tunnel advance support, including pipe-roof support and tunnel mouth template support, wherein the pipe-roof support includes a steel arch 11 and a grouting pipe 12, the curvature of the steel arch is the same as the curvature of the tunnel mouth, the steel arch is arranged at the tunnel mouth, a fixed ring 13 is arranged on the steel arch, the grouting pipe is penetrated on the fixed ring and penetrated into the soil at the upper part of the tunnel mouth, the penetration of the grouting pipe is arranged to be inclined upward, wherein the tunnel mouth template support is arranged at a pre-excavated tunnel;

[0037] The tunnel mouth formwork support includes an internal corrugated plate 1, an externally detachable corrugated plate 2, and an assembled inverted arch bottom plate 3; the characteristic is that the internal corrugated plate is composed of an internal corrugated plate and reinforcing ribs 7, wherein the reinforcing ribs are inserted into holes arranged between the crests and troughs of the internal corrugated plate, and the internal corrugated plate is abutted against and fully distributed on the inner wall of the tunnel; the bottom of the internal corrugated plate is connected to the assembled inverted arch bottom plate, the assembled inverted arch bottom plate is a prefabricated composite bottom plate, and is a prefabricated reinforced concrete structure, the side surfaces of the two ends of the assembled inverted arch bottom plate are in contact with the arc surface of the tunnel bottom, and the cross-section of the assembled inverted arch bottom plate is a shape of large at the top and small at the bottom. The upper surfaces of both ends of the assembled inverted arch bottom plate are provided with a first mounting groove 4 and a second mounting groove 5, the first mounting groove and the second mounting groove are extended and arranged in parallel along the length direction of the assembled inverted arch bottom plate, and the spacing is set equal to the thickness of the secondary lining, and the built-in corrugated plate is installed in the first mounting groove; the gap between the built-in corrugated plate and the inner wall of the tunnel is filled with high-strength concrete as the initial support of the tunnel, and the externally removable corrugated plate is installed after the concrete solidifies; the externally removable corrugated plate is installed in the second mounting groove, and the space between the externally removable corrugated plate and the built-in corrugated plate is filled with cast-in-place reinforced concrete as the secondary lining.

[0038] An end template is set at the end face of the externally dismantled corrugated plate, a secondary lining steel cage structure is arranged between the externally dismantled corrugated plate and the internally dismantled corrugated plate, and the steel cage structure and the externally dismantled corrugated plate are installed by a secondary lining trolley.

[0039] The first installation groove is a U-shaped groove with the groove facing upward. The first installation groove is installed on the assembly arch bottom plate through bolt embedded parts. An internal corrugated plate is installed in the first installation groove, and a waterproof sealing material is filled in the gap between the side wall of the first installation groove and the internal corrugated plate.

[0040] The first installation groove and the second installation groove are both continuously arranged throughout the length. The reinforcing ribs passing through the built-in corrugated plate are post-tensioned prestressed ribs. Anchor seats 6 are arranged in the two rows of first installation grooves at both ends of the assembled arch bottom plate for anchoring the post-tensioned prestressed ribs. When the strength of the high-strength concrete filled between the built-in corrugated plate and the inner wall of the tunnel reaches 75%, the prestressed ribs are tensioned.

[0041] Embodiment 2:

[0042] Since advance support requires pre-support when excavating the tunnel, a tunnel entrance will generally be constructed first to facilitate the subsequent entry of machinery and further excavation of the tunnel. The advance support of the tunnel entrance needs to be set up according to the support requirements of the tunnel.

[0043] During construction, pipe shed support is constructed according to the setting requirements. The tunnel entrance is excavated first to form the construction face. A steel arch is installed at the corresponding tunnel entrance. The steel arch is close to the inside of the tunnel entrance. Then, holes are drilled on the working surface to be excavated. A fixed ring is installed on the steel arch at the corresponding drilling position. The grouting pipe is inserted on the fixed ring and penetrated into the soil above the tunnel entrance. The grouting pipe is inserted in an inclined upward direction. After the grouting pipe is installed, grouting construction is carried out after passing the inspection.

[0044] After that, the tunnel mouth formwork support formwork construction is carried out. First, the internal corrugated plate and the externally dismantled corrugated plate are made. The internal corrugated plate is provided with a reinforcement hole. According to the support order of the tunnel, the prefabricated components are placed and connected, and the first installation groove and the second installation groove are installed. The lining trolley enters the tunnel for preliminary support construction, and the internal corrugated plate is fixedly installed and filled with high-strength concrete. The prestressed reinforcement bars are subsequently tensioned. After the final setting, the lining trolley performs the secondary lining construction, and the secondary lining reinforced concrete steel cage is installed and the externally dismantled corrugated plate is installed, and concrete is poured. When the lining trolley performs the secondary lining construction, the secondary lining construction is segmented. After the secondary lining is poured, it immediately moves forward to the next lining condition without waiting for the final setting of the secondary lining. The removable corrugated plate can be removed and reused after the final setting of the previous lining structure. The construction steps of the tunnel mouth formwork support are as follows:

[0045] S1: Make internal corrugated panels and external corrugated panels;

[0046] Using engineering drawings, calculate tunnel section parameters and determine the shape and size of the support; based on the shape and size, use hydraulic forming machinery to prefabricate corrugated plates, with holes reserved on the built-in corrugated plates to fix the reinforcing ribs; remove dirt from the surface of the corrugated plates; make them on a brushing machine and a rubbing machine, using the axial movement of the upper group of grinding rollers to brush on the metal surface to obtain wavy patterns, with grouting holes reserved on both the built-in corrugated plates and the external corrugated plates;

[0047] S2: placement and connection of prefabricated components;

[0048] The assembly inverted arch bottom plate is installed and placed at the bottom of the tunnel, the assembly inverted arch bottom plates are connected by force transmission rods, and the gaps therebetween are sealed with waterproof materials; the first installation groove and the second installation groove are installed on the assembly inverted arch bottom plate;

[0049] The laying and assembly of the inverted arch bottom plate is carried out in sections of 50m each. The internal corrugated plates are laid along the tunnel section. Two adjacent corrugated plates along the tunnel depth direction are connected by bolts. After the installation and connection of the components are completed, concrete is filled into the grouting holes of the corrugated plate wall. When the strength of the high-strength concrete filled between the internal corrugated plate and the inner wall of the tunnel reaches 75%, the prestressed tendons are tensioned. Subsequently, the gap between the first installation groove and the internal corrugated plate is sealed with waterproof sealing materials.

[0050] S3: Secondary lining pouring;

[0051] A steel cage is constructed outside the built-in corrugated plate by a lining trolley, which is arranged on one side of the steel cage and welded to the surface of the built-in corrugated plate by spot welding. The externally dismantled corrugated plate is installed in the second installation groove, and the externally dismantled corrugated plate is close to the outside of the steel cage. The two bottom lower ends of the externally dismantled corrugated plate are connected to the side plate of the second installation groove by bolts. The end formwork is then constructed for closed pouring, and then concrete is poured as a secondary lining;

[0052] S4: Continuous construction of lining trolley

[0053] After the secondary lining is poured, it will immediately move forward to the next lining condition without waiting for the final setting of the secondary lining. After the secondary lining construction of the previous condition is completed, the lining trolley will immediately move to the next condition for continuous construction. After the secondary lining of the previous condition is finally set, the external formwork and end formwork will be removed for the next condition construction, thereby realizing the continuous construction of the tunnel lining.

[0054] A waterproof structure is arranged between the two built-in corrugated plates, and the waterproof structure is composed of waterproof coiled material, filling material, embedded water stop strip and sealant.

[0055] In step S2, the assembled arch bottom plate is laid on the fine mortar layer, and waterproof materials are arranged at the joints of the assembled arch bottom plate. The waterproof structure is composed of waterproof membrane, filling materials, waterstop and sealant; wherein the waterstop is horizontally symmetrically buried in the upper part of the assembled arch bottom plate at both ends, the deformation joint is filled with filling materials, and the upper part of the deformation joint is sealed.

[0056] The tensioning equipment includes an anchor seat, an anchor head and a positioning plate. The anchor seat is installed on a side plate of the first installation groove away from the tunnel side wall. The anchor head is in the form of two clips for fixing the reinforcement ribs, which are connected to the anchor seat through the positioning plate. The reinforcement ribs in the first installation groove arranged at both ends of the bottom plate of the assembled invert are tensioned at the same time. During tensioning, the reinforcement ribs will not touch or interfere with the bottom of the built-in corrugated plate.

[0057] The above is only a preferred embodiment of the present invention, and does not limit the structure of the present invention in any form. Any simple modification, equivalent change or modification made to the above embodiment according to the technical essence of the present invention still falls within the scope of the technical solution of the present invention.

Claims

1. A soft surrounding rock tunnel advance support, comprising a pipe-roof support and a tunnel mouth template support, wherein the pipe-roof support comprises a steel arch and a grouting pipe, the curvature of the steel arch is the same as that of the tunnel mouth, the steel arch is arranged at the tunnel mouth, a fixed ring is arranged on the steel arch, the grouting pipe is penetrated on the fixed ring and penetrated into the soil at the upper part of the tunnel mouth, the penetration of the grouting pipe is arranged to be inclined upward, wherein the tunnel mouth template support is arranged at a pre-excavated tunnel, and the tunnel mouth template support comprises an internal corrugated plate, an externally detachable corrugated plate, and an assembled inverted arch bottom plate; characterized in that: The built-in corrugated plate is composed of a built-in corrugated plate and reinforcing ribs, wherein the reinforcing ribs are inserted into holes set between the crests and troughs of the built-in corrugated plate, and the built-in corrugated plate is close to and fully distributed on the inner wall of the tunnel; the bottom of the built-in corrugated plate is connected to the assembled arch bottom plate, the assembled arch bottom plate is a prefabricated composite bottom plate, and is a prefabricated reinforced concrete structure, the side surfaces of the two ends of the assembled arch bottom plate are in contact with the curved surface of the tunnel bottom, and the cross-section of the assembled arch bottom plate is a shape of large at the top and small at the bottom; the upper surfaces of the two ends of the assembled arch bottom plate are both provided with A first installation groove and a second installation groove are provided, the first installation groove and the second installation groove are extended and arranged in parallel along the length direction of the assembled inverted arch bottom plate, and the spacing is set equal to the thickness of the secondary lining, the built-in corrugated plate is installed in the first installation groove; the gap between the built-in corrugated plate and the inner wall of the tunnel is filled with high-strength concrete as the initial support of the tunnel, and the externally removable corrugated plate is installed after the concrete solidifies; the externally removable corrugated plate is installed in the second installation groove, and the space between the externally removable corrugated plate and the built-in corrugated plate is filled with cast-in-place reinforced concrete as the secondary lining.

2. The advance support of a soft surrounding rock tunnel according to claim 1 is characterized by: An end template is set at the end face of the externally dismantled corrugated plate, a secondary lining steel cage structure is arranged between the externally dismantled corrugated plate and the internally dismantled corrugated plate, and the steel cage structure and the externally dismantled corrugated plate are installed by a secondary lining trolley.

3. The advance support of a soft surrounding rock tunnel according to claim 1 is characterized by: The first installation groove is a U-shaped groove with the groove facing upward. The first installation groove is installed on the assembly arch bottom plate through bolt embedded parts. An internal corrugated plate is installed in the first installation groove, and a waterproof sealing material is filled in the gap between the side wall of the first installation groove and the internal corrugated plate.

4. The advance support of a soft surrounding rock tunnel according to claim 2 is characterized by: The first installation groove and the second installation groove are both continuously arranged throughout the length. The reinforcing ribs passing through the built-in corrugated plate are post-tensioned prestressed tendons. Anchor seats are arranged in the two rows of first installation grooves at both ends of the assembled arch bottom plate for anchoring the post-tensioned prestressed tendons. The prestressed tendons are tensioned when the strength of the high-strength concrete filled between the built-in corrugated plate and the inner wall of the tunnel reaches 75%.

5. According to the construction method of advance support for soft surrounding rock tunnels described in any one of claims 1 to 4, during construction, pipe shed support is first constructed according to the setting requirements, the tunnel entrance is first excavated to form a construction face, a steel arch is installed at the corresponding tunnel entrance, the steel arch is close to the inside of the tunnel entrance, and then a hole is drilled at the working face to be excavated, and a fixed ring is installed on the steel arch at the corresponding drilling position, the grouting pipe is penetrated on the fixed ring and penetrated into the soil above the tunnel entrance, and the grouting pipe is penetrated to be inclined upward; After the grouting pipe is installed, grouting construction is carried out after passing the inspection; After that, the tunnel mouth formwork support formwork construction is carried out. First, the internal corrugated plate and the externally removable corrugated plate are made, wherein the internal corrugated plate is provided with a reinforcement hole. According to the support order of the tunnel, the prefabricated components are placed and connected, the first installation groove and the second installation groove are installed, and the lining trolley enters the tunnel for preliminary support construction, and the internal corrugated plate is fixedly installed and filled with high-strength concrete. Subsequently, the prestressed reinforcement bars are tensioned. After final setting, the lining trolley carries out secondary lining construction, and the secondary lining reinforced concrete steel cage is installed and the externally removable corrugated plate is installed, and concrete is poured; when the lining trolley carries out the secondary lining construction, the secondary lining construction is segmented, and after the secondary lining is poured, it immediately moves forward to the next lining condition without waiting for the final setting of the secondary lining; the removable corrugated plate can be removed and reused after the final setting of the previous lining structure, which is characterized in that, The construction steps of tunnel mouth formwork support are as follows: S1: Make internal corrugated panels and external corrugated panels; Using engineering drawings, calculate tunnel section parameters and determine the shape and size of the support; based on the shape and size, use hydraulic forming machinery to prefabricate corrugated plates, with holes reserved on the built-in corrugated plates to fix the reinforcing ribs; remove dirt from the surface of the corrugated plates; make them on a brushing machine and a rubbing machine, using the axial movement of the upper group of grinding rollers to brush on the metal surface to obtain wavy patterns, with grouting holes reserved on both the built-in corrugated plates and the external corrugated plates; S2: placement and connection of prefabricated components; The assembly inverted arch bottom plate is installed and placed at the bottom of the tunnel, the assembly inverted arch bottom plates are connected by force transmission rods, and the gaps therebetween are sealed with waterproof materials; the first installation groove and the second installation groove are installed on the assembly inverted arch bottom plate; The laying and assembly of the inverted arch bottom plate is carried out in sections of 50m each. The internal corrugated plates are laid along the tunnel section. Two adjacent corrugated plates along the tunnel depth direction are connected by bolts. After the installation and connection of the components are completed, the grouting holes of the corrugated plate wall are filled with concrete. When the strength of the high-strength concrete filled between the internal corrugated plate and the inner wall of the tunnel reaches 75%, the prestressed tendons are tensioned. Subsequently, the gap between the first installation groove and the internal corrugated plate is sealed with waterproof sealing materials. S3: Secondary lining pouring; A steel cage is constructed outside the built-in corrugated plate by a lining trolley, which is arranged on one side of the steel cage and welded to the surface of the built-in corrugated plate by spot welding. The externally dismantled corrugated plate is installed in the second installation groove, and the externally dismantled corrugated plate is close to the outside of the steel cage. The two bottom lower ends of the externally dismantled corrugated plate are connected to the side plate of the second installation groove by bolts. The end formwork is then constructed for closed pouring, and then concrete is poured as a secondary lining; S4: Continuous construction of lining trolley After the secondary lining is poured, it will immediately move forward to the next lining condition without waiting for the final setting of the secondary lining. After the secondary lining construction of the previous condition is completed, the lining trolley will immediately move to the next condition for continuous construction. After the secondary lining of the previous condition is finally set, the external formwork and end formwork will be removed for the next condition construction, thereby realizing the continuous construction of the tunnel lining.

6. The construction method of a prefabricated corrugated plate tunnel formwork according to claim 5, characterized in that: A waterproof structure is arranged between the two built-in corrugated plates, and the waterproof structure is composed of waterproof coiled material, filling material, embedded water stop strip and sealant.

7. The construction method of a prefabricated corrugated plate tunnel formwork according to claim 5, characterized in that: In step S2, the assembled arch bottom plate is laid on the fine mortar layer, and waterproof materials are arranged at the joints of the assembled arch bottom plate. The waterproof structure is composed of waterproof membrane, filling materials, waterstop and sealant; wherein the waterstop is horizontally symmetrically buried in the upper part of the assembled arch bottom plate at both ends, the deformation joint is filled with filling materials, and the upper part of the deformation joint is sealed.

8. The construction method of a prefabricated corrugated plate tunnel formwork according to claim 5, characterized in that: The internal corrugated plate is made of steel plate, and the external corrugated plate is made of aluminum plate.

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