Tunnel structure crossing karst cave and construction method thereof
By using arched corrugated steel plates as steel arches, crossing the cave and forming a temporary stress-bearing structure, the damage to the cave water discharge channel by traditional construction methods and the difficulty in construction of formwork brackets is solved, and the safety and durability of tunnel construction are improved. .
Patent Information
- Application Number
- CN202411665858.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-20
- Publication Date
- 2025-02-14
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
In the construction of tunnels, when encountering hall-type caves, traditional treatment plans for backfilling or setting up cast-in-place beam bridges to span the caves, there are problems such as destroying the original cave water discharge channel or formwork bracket construction and difficulty in dismantling. .
The arched corrugated steel plate is used as the steel arch. The arch foot of the steel arch is connected to the cave wall, forming a temporary stress-bearing structure across the cave, and a concrete arch and filler area are set up on it to avoid backfill treatment of the cave. and template bracket use.
This method avoids damage to the original cave water discharge channel, simplifies the construction process, reduces costs, and improves the safety and durability of the tunnel.
Smart Images
Figure CN119435049A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of tunnel structure construction, and in particular to a tunnel structure spanning a karst cave and a construction method thereof. Background Art
[0002] In my country's karst areas, especially in Guangxi, Guizhou, Yunnan and other places, large hall caves are often encountered during tunnel construction. When a tunnel passes through a hall cave, the structural design must consider not only the impact load and vehicle load from the top of the cave, but also the protection of the natural drainage channel of the cave and whether the bottom structure is sufficient to bear the load; it must consider not only the safety factors during the construction period, but also the long-term operational safety, structural durability and maintenance convenience. In current tunnel construction, when encountering a hall-type cave, the bottom of the cave is generally backfilled or a cast-in-place beam bridge is set up to cross the cave. However, the treatment plan of backfilling the bottom of the cave has a great impact on the natural drainage channel of the cave, destroys the original cave drainage channel, and is difficult to backfill densely, with a large amount of backfill and high cost; the treatment plan of setting up a scaffolding formwork support system in the cave and then setting up a cast-in-place beam bridge to cross the cave has the problem of difficult formwork support construction and difficult removal in the later stage. Summary of the invention
[0003] The purpose of the present invention is to overcome the shortcomings of the prior art in that, when encountering a hall-type karst cave in tunnel construction, the traditional solution of backfilling the bottom of the karst cave or setting a cast-in-place beam bridge to cross the karst cave has the disadvantages of damaging the original karst cave drainage channel or the difficulty in construction and removal of the formwork support, and to provide a tunnel structure crossing the karst cave and a construction method thereof.
[0004] In a first aspect, the present invention provides a tunnel support structure spanning a cave, comprising:
[0005] A steel arch, wherein the arch foot of the steel arch is connected to the wall of the cave, the steel arch is located below the tunnel, the steel arch is an arched corrugated steel plate, the corrugated steel plate has a corrugated cross-section, the corrugation extension direction on the cross-section is the width direction of the corrugated steel plate, the direction perpendicular to the corrugation extension direction is the length direction of the corrugated steel plate, the corrugated steel plate is bent into an arch along the length direction, and the width direction of the corrugated steel plate is consistent with the width direction of the tunnel.
[0006] A concrete arch is disposed above the steel arch.
[0007] A filling area is provided above the concrete arch and is used for filling to form a tunnel foundation.
[0008] The present invention provides a tunnel support structure across a karst cave, wherein the steel arch is an arched corrugated steel plate, which is lightweight and can be easily erected using common lifting equipment. The corrugated steel plate is usually processed into various wave-shaped plates by a roller cold bending process. This wave-shaped design can increase the cross-sectional inertia moment of the steel plate, thereby improving its bending rigidity, thereby making the steel arch have a higher bearing capacity, and no additional steel structure is required as a supporting skeleton. The direction in which the corrugations extend on the cross section is the width direction of the corrugated steel plate, and the direction perpendicular to the direction in which the corrugations extend is the length direction of the corrugated steel plate. The corrugated steel plate is bent into an arch along the length direction, and the width direction of the corrugated steel plate is consistent with the width direction of the tunnel. This method ensures that the corrugation extension direction of the corrugated steel plate is the arch width direction of the steel arch, ensures that the two ends of the corrugated steel plate along its length direction (the end faces with corrugated cross-sections) can be supported on the cave wall of the karst cave as arch feet, and can ensure that the corrugated steel plate has stronger stability when forming the steel arch. If the two ends of the corrugated steel plate along the extension direction of its corrugations are not effectively supported, the corrugated steel plate cannot form a stable supporting structure. The arch foot of the steel arch is connected to the cave wall of the karst cave, so that the steel arch can be used as a temporary load-bearing structure across the karst cave. The steel arch can be used as a bottom formwork for the steel bar binding and concrete pouring of the concrete arch, bearing the deadweight load of the concrete arch before reaching the design strength, and can also be used as a temporary platform for operators, small equipment, materials, etc. The concrete arch is the main load-bearing structure, used to bear the deadweight of the structure, the upper structure load and the dynamic load, etc. The filling area is used for filling to form the tunnel foundation. By using the arched corrugated steel plate as the steel arch to span the cave and serve as a temporary load-bearing structure, compared with the treatment solution of backfilling the cave bottom in the prior art, there is no need to backfill the cave, thus avoiding damage to the original cave drainage channel. Compared with the treatment solution of setting a cast-in-place beam bridge to span the cave in the prior art, there is no need to set up a scaffolding formwork support system in the cave, thus avoiding the problems of difficult construction of the formwork support and difficulty in later removal.
[0009] The corrugated steel plate has a corrugated cross section, which can increase the section inertia moment of the corrugated steel plate. The arched corrugated steel plate is located at the bottom of the concrete arch as the steel arch, and can also bear the tension of the arch bottom after the concrete arch reaches the design strength.
[0010] There are many ways to connect the arch foot of the steel arch to the cave wall. For example, the arch foot is directly connected to the cave wall through anchor bolts. For example, a groove or hole for placing the arch foot can be drilled on the cave wall, and the arch foot is connected to the cave wall through the groove or the hole.
[0011] The strength of the filler in the filler area is not less than 0.5MPa, and ceramsite concrete or pumice concrete can be used, which can reduce the deadweight of the structure, improve construction safety and convenience, and save construction costs. The height of the filler in the filler area can be level with the top of the concrete arch, or higher than the top of the concrete arch.
[0012] Temporary formwork or permanent formwork can be provided on the sides of the concrete arch and the filling area so as to smoothly form the concrete or filling material during pouring. The temporary formwork can be a wooden formwork, and the permanent formwork can be a metal formwork.
[0013] Preferably, the steel arch includes a plurality of arch pieces, all of which are arched corrugated steel plates, arranged along the width direction of the corrugated steel plates, and two adjacent arch pieces are connected to each other. This solution can reduce the size and weight of a single arch component, facilitate the transportation of a single arch component to the edge of a karst cave through a built tunnel, and also facilitate the lifting, transportation and installation of a single arch component. The two adjacent arch pieces can be connected to each other by bolt connection, rivet connection or welding.
[0014] Preferably, shear nails are provided on a plurality of the arch pieces, and the shear nails are welded to the arch pieces. The shear nails are used to be embedded in the concrete arch, so as to strengthen the connection between the corrugated steel plate and the concrete arch and improve the integrity between the two.
[0015] Preferably, baffles are provided on both sides of the steel arch, and the baffles on both sides are provided with anti-deformation components. The baffles are used as lateral formwork during the pouring of concrete in the concrete arch and during the filling construction of the filling area. The baffles can be made of aluminum plates, steel plates, etc. The bottom edge of the baffle is connected to the steel arch by bolts or welding. The anti-deformation component can be arranged between the baffle and the arch surface of the steel arch, such as a triangular rib, or can be arranged between the baffles respectively located on both sides, such as a tension rod. The anti-deformation component can improve the ability of the baffle to resist lateral deformation. The tension rod can be a steel bar, a screw rod or a high-strength plastic rod, and its two ends are respectively fixedly connected to the baffles on both sides.
[0016] Preferably, a groove is provided on the cave wall of the karst cave, and the arch foot of the steel arch is connected to the groove. The groove is formed by grooving the cave wall of the karst cave, and the groove can make the originally uneven cave wall relatively flat, which is convenient for connecting the arch foot of the steel arch with the cave wall. At the same time, the groove can also play a role in positioning and limiting the sliding of the arch foot, thereby improving the safety of installing the steel arch.
[0017] Preferably, the filler area is provided with a hollow structure, which can reduce the amount of the filler material, further reduce the weight of the structure, and save construction costs. The hollow structure can be a PVC pipe, a corrugated pipe, or a hollow sphere.
[0018] In a second aspect, the present invention provides a tunnel structure across a cave, comprising a protective structure, wherein the protective structure is located above a tunnel support structure across a cave as described in any one of claims 1 to 7, wherein the protective structure comprises a corrugated steel protective arch, a buffer layer and a tunnel inner lining, wherein the bottom of the corrugated steel protective arch is connected to the tunnel support structure, the buffer layer is arranged on the inner side of the corrugated steel protective arch, and the tunnel inner lining is arranged on the inner side of the buffer layer.
[0019] The present invention provides a tunnel structure spanning a karst cave, wherein the corrugated steel protective arch serves as an impact protection structure (to prevent the tunnel from being damaged by falling rocks above the karst cave), and has the following advantages: the corrugated steel protective arch is easy to construct, and can quickly form a safety protection structure, thereby improving safety during construction; the corrugated steel protective arch has high strength and high toughness properties, and has a better protective effect against the impact load of falling rocks; the corrugated steel protective arch has a lower deadweight than a concrete structure, and can reduce the deadweight of the protective structure, while the corrugated steel plates of the protective arch can be replaced or superimposed to achieve the purpose of rapid and convenient repair; the corrugated steel protective arch can also serve as a structural support skeleton for the buffer layer.
[0020] As a protective structure, the buffer layer mainly functions to further disperse the impact load and protect the structures or vehicles inside it. The combination of the corrugated steel protective arch and the buffer layer has the following advantages: compared with the traditional structure of a thick concrete arch + a backfilled anti-impact layer on the top, it saves more engineering costs and improves the safety and durability of the tunnel; it can be used as an outer formwork for the inner lining of the tunnel, solving the difficulties in erecting the outer formwork for the inner lining of the tunnel, further saving the cost of the outer formwork, and increasing the convenience of construction; it can reduce the design thickness of the inner lining of the tunnel, further reducing the weight of the protective structure and saving construction costs. The buffer layer can be made of a variety of materials, such as rubber, foam plastics, and spring pads.
[0021] The inner lining of the tunnel serves as a protective safety reserve for the tunnel and can be a steel structure or a concrete structure. The inner lining of the tunnel can be optimized or cancelled according to the structural stress analysis to further reduce the deadweight of the structure and save construction costs.
[0022] Preferably, the buffer layer is a rubber block or a foam plastic block. The rubber block and the foam plastic block are convenient for fixing to the corrugated steel protective arch, for example, by bolts, screws, binding tape or gluing.
[0023] Preferably, the buffer layer is fixed to the corrugated steel protective arch by bolts. The bolt connection method ensures a stable connection and can achieve the purpose of convenient replacement.
[0024] Preferably, the inner lining of the tunnel is a reinforced concrete structure, and the thickness of the reinforced concrete structure is 300mm-600mm.
[0025] In a third aspect, the present invention provides a method for constructing a tunnel structure across a karst cave, comprising the following steps:
[0026] S1: using a truck crane to hoist a steel arch that needs to span a cave to a designated installation position of the cave, and installing the arch foot of the steel arch on the wall of the cave;
[0027] S2: Arranging and tying steel bars on the steel arch, and then pouring concrete to form a concrete arch;
[0028] S3: Carry out filling construction on the filling area and fill it to the predetermined elevation to form the tunnel foundation;
[0029] S4: hoisting the corrugated steel protection arch onto the tunnel foundation, and fixing the corrugated steel protection arch to the tunnel foundation;
[0030] S5: fixing the buffer layer to the inner side of the corrugated steel protective arch by bolts;
[0031] S6: Using the buffer layer as a template to construct the inner lining of the tunnel inside the buffer layer, and completing the construction.
[0032] The present invention provides a construction method for a tunnel structure across a karst cave. By erecting the steel arch on the karst cave of the tunnel and constructing a concrete arch, the karst cave does not need to be backfilled, thereby avoiding damage to the original karst cave drainage channel, and there is no need to erect a scaffolding formwork support system in the karst cave, thereby avoiding the problem of difficult construction of the formwork support and difficulty in dismantling it later. By constructing the protective structure, the safety and durability of the tunnel are improved, and the construction cost is saved.
[0033] Compared with the prior art, the present invention has the following beneficial effects:
[0034] 1. The present invention provides a tunnel support structure across a karst cave, in which the arched corrugated steel plate is used as the steel arch to span the karst cave and as a temporary force-bearing structure. Compared with the treatment solution of backfilling the bottom of the karst cave in the prior art, there is no need to backfill the karst cave, thereby avoiding damage to the original karst cave drainage channel. Compared with the treatment solution of setting a cast-in-place beam bridge across the karst cave in the prior art, there is no need to set up a scaffolding formwork support system in the karst cave, thereby avoiding the problem of difficult construction of the formwork support and difficulty in dismantling it in the later stage.
[0035] 2. The present invention provides a tunnel structure across a karst cave, and the following advantages are achieved through the corrugated steel protective arch: the corrugated steel protective arch is easy to construct, can quickly form a safety protection structure, and improve the safety during construction; the corrugated steel protective arch has high strength and high toughness properties, and has a better protective effect on the impact load of falling rocks; the corrugated steel protective arch has a lower deadweight than the concrete structure, which can reduce the deadweight of the protective structure, and can replace or superimpose the corrugated steel plate of the protective arch to achieve the purpose of fast and convenient repair; the corrugated steel protective arch can also be used as a structural support skeleton of the buffer layer. The combination of the corrugated steel protective arch and the buffer layer achieves the following advantages: compared with the traditional heavy concrete arch + top backfill anti-impact layer structure, it saves more engineering costs and improves the safety and durability of the tunnel; it can be used as the outer formwork of the inner lining of the tunnel, which solves the difficulty of the inner lining of the tunnel in the erection of the outer formwork, further saves the cost of the outer formwork, and increases the convenience of construction; it can reduce the design thickness of the inner lining of the tunnel, further reduce the weight of the protective structure, and save construction costs.
[0036] 3. The present invention provides a construction method for a tunnel structure across a karst cave. By erecting the steel arch on the karst cave of the tunnel and constructing a concrete arch, the karst cave does not need to be backfilled, thus avoiding damage to the original karst cave drainage channel, and there is no need to erect a scaffolding formwork support system in the karst cave, thus avoiding the problem of difficult formwork support construction and difficult removal in the later stage. By constructing the protective structure, the safety and durability of the tunnel are improved, and the construction cost is saved. BRIEF DESCRIPTION OF THE DRAWINGS
[0037] Figure 1 A schematic diagram of a tunnel structure spanning a cave.
[0038] Figure 2 for Figure 1 Section view along the AA cutting line.
[0039] Figure 3 for Figure 1 Section view along the BB section line.
[0040] Figure 4 A three-dimensional schematic diagram of a steel arch.
[0041] Markings in the figure:
[0042] 1- steel arch, 2- concrete arch, 3- filling area, 4- hollow structure, 5- groove, 6- cave, 7- corrugated steel protective arch, 8- buffer layer, 9- tunnel inner lining, 10- baffle. DETAILED DESCRIPTION
[0043] The present invention is further described in detail below in conjunction with specific embodiments. However, this should not be understood as the scope of the above subject matter of the present invention being limited to the following embodiments, and all technologies realized based on the content of the present invention belong to the scope of the present invention.
[0044] Unless otherwise specified, in the description of the specific embodiments of the present invention, the terms indicating the orientation or position relationship such as "up", "down", "left", "right", "center", "inside", "outside", etc. are all expressions based on the orientation or position relationship shown in the drawings, or are the orientation or position relationship when the invented product / equipment / device is usually used. These terms of orientation or position relationship are only for the convenience of describing the scheme of the present invention or simplifying the description in the specific embodiments, so as to facilitate the technicians to quickly understand the scheme, and do not indicate or imply that a specific device / component / element must have a specific orientation, or be constructed and operated in a specific position relationship, and therefore cannot be understood as a limitation on the present invention.
[0045] In addition, if the terms "horizontal", "vertical", "overhanging", "parallel" and the like appear, it does not mean that the corresponding devices / components / elements are required to be absolutely horizontal or vertical or overhanging or parallel, but may be slightly tilted or have deviations. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but may be slightly tilted. Alternatively, it can be simplified to mean that the corresponding devices / components / elements are set in directions such as "horizontal", "vertical", "overhanging", "parallel", etc., and can have an error / deviation of ±10% relative to the corresponding direction setting, more preferably an error / deviation within ±8%, more preferably an error / deviation within ±6%, more preferably an error / deviation within ±5%, and more preferably an error / deviation within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its role in the scheme of the present invention.
[0046] In addition, the expressions “first”, “second”, “third”, etc., which appear in the terms, are merely used to distinguish the description of the same or similar components and should not be understood as emphasizing or implying the relative importance of specific components.
[0047] In addition, in the description of the embodiments of the present invention, "several", "plurality" and "a number" represent at least 2. It can be any number such as 2, 3, 4, 5, 6, 7, 8, 9, and even more than 9.
[0048] In addition, in the description of the technical solution of the present invention, unless otherwise clearly specified / defined / restricted, the terms "set", "install", "connect", "connected", "provided with", "laid", and "arranged" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection, and can be welding, riveting, bolting, threading, and other commonly used connection means in the field. This connection can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection, or an indirect connection through an intermediate medium, and it can be the internal connection of two elements.
[0049] Example 1
[0050] like Figure 1-Figure 3 As shown, a tunnel support structure spanning a karst cave includes a steel arch 1, a concrete arch 2 and a filling area 3.
[0051] The arch foot of the steel arch 1 is connected to the wall of the cave 6. The steel arch 1 is located below the tunnel. The steel arch 1 is an arched corrugated steel plate with a corrugated cross-section. Specifically, the cross-sectional shape of the corrugated steel plate can be a continuous sinusoidal wave shape. The direction in which the corrugations extend on the cross-section is the width direction of the corrugated steel plate, and the direction perpendicular to the direction in which the corrugations extend is the length direction of the corrugated steel plate. The corrugated steel plate is bent into an arch along the length direction, and the width direction of the corrugated steel plate is consistent with the width direction of the tunnel. The arch width direction of the steel arch 1 is consistent with the width direction of the tunnel, and the span direction of the steel arch 1 is consistent with the length direction of the tunnel. Figure 4 As shown, a three-dimensional schematic diagram of the arched corrugated steel plate as a steel arch 1 is shown, and the direction of the arrow in the figure is the extension direction of the corrugations of the corrugated steel plate, which is also the arch width direction of the steel arch 1.
[0052] The concrete arch 2 is arranged above the steel arch 1. When the concrete arch 2 is constructed, the steel arch 1 can be used as a bottom mold so that the bottom shape of the concrete arch 2 fits the steel arch 1.
[0053] The filling area 3 is arranged above the concrete arch 2, and the filling area 3 is used for filling to form a tunnel foundation. The filling can be ceramsite concrete or pumice concrete.
[0054] In an optional embodiment, the steel arch 1 may include a plurality of arch pieces, each of which is an arched corrugated steel plate, and the plurality of arch pieces are arranged along the width direction of the corrugated steel plate, and two adjacent arch pieces are connected to each other. The two adjacent arch pieces may be connected by bolts, rivets or welding. The width of the arch piece may be 1.0m-2.0m, and the specific width may be 1.0m, 1.2m, 1.5m, 1.8m or 2.0m.
[0055] In an optional embodiment, shear nails may be provided on a plurality of the arch pieces, and the shear nails are welded to the arch pieces. The shear nails may be arranged at a number of 10 to 25 per square meter, and specifically may be arranged at a number of 10, 12, 16, 18, 20 or 25 per square meter.
[0056] In an optional embodiment, baffles 10 may be provided on both sides of the steel arch 1. The baffles 10 may specifically be steel plates, the bottom edge of the steel plates being welded to the steel arch 1, and the top edge of the steel plates being flush with the top of the filling area 3. The baffles 10 on both sides may be provided with anti-deformation components. The anti-deformation components may be tension rods arranged between the baffles 10 on both sides, and the tension rods may specifically be steel bars or screws, the two ends of the steel bars being welded to the steel plates, and the two ends of the screws being bolted to the steel plates. The diameter of the steel bars or the screws may be selected from 6mm to 22mm according to actual conditions, and the specific diameters may be 6mm, 8mm, 10mm, 12mm, 14mm, 16mm, 18mm, 20mm and 22mm.
[0057] In an optional embodiment, a groove 5 may be provided on the wall of the cave 6, and the arch foot of the steel arch 1 is connected to the groove 5. The groove 5 may be provided with an embedded bolt, and the embedded bolt can be connected to the arch foot of the steel arch 1.
[0058] In an optional embodiment, the filling area 3 may be provided with a hollow structure 4. The hollow structure 4 may be a PVC pipe, the axial direction of which is consistent with the arch width direction of the steel arch 1. The diameter of the PVC pipe is 100 mm-200 mm, and the specific diameter may be 100 mm, 110 mm, 125 mm, 160 mm or 200 mm. The distance between two adjacent PVC pipes in the horizontal direction and the vertical direction is 0.4 m-0.6 m, and the specific distance may be 0.4 m, 0.5 m and 0.6 m.
[0059] Example 2
[0060] like Figure 1-Figure 3 As shown, a tunnel structure across a cave includes a protective structure, which is located above the tunnel support structure across a cave described in Example 1. The protective structure includes a corrugated steel protective arch 7, a buffer layer 8 and a tunnel inner lining 9. The bottom of the corrugated steel protective arch 7 is connected to the tunnel support structure, the buffer layer 8 is arranged on the inner side of the corrugated steel protective arch 7, and the tunnel inner lining 9 is arranged on the inner side of the buffer layer 8.
[0061] In an optional embodiment, the buffer layer 8 may be a rubber block or a foam plastic block.
[0062] In an optional embodiment, the buffer layer 8 can be fixed to the corrugated steel protective arch 7 by bolts.
[0063] In an optional embodiment, the inner lining 9 of the tunnel may be a reinforced concrete structure. The thickness of the reinforced concrete structure may be 300 mm-600 mm, and the specific thickness may be 300 mm, 350 mm, 400 mm, 450 mm, 500 mm, 550 mm and 600 mm.
[0064] Example 3
[0065] The present invention provides a construction method for a tunnel structure across a karst cave, and specifically describes the construction steps of a tunnel structure across a karst cave described in Example 2, which includes the following steps:
[0066] S1: grooves 5 are cut at predetermined positions on the wall of the cave 6, and embedded bolts are installed. A truck crane is used to hoist several arch pieces to the designated installation positions of the cave 6, all the arch pieces are arranged along the arch width direction of the steel arch 1, and the arch feet of the arch pieces are installed in the grooves 5, and the arch feet are connected to the embedded bolts. Two adjacent arch pieces are connected by bolts to form a steel arch 1.
[0067] S2: Install baffles 10 on both sides of the steel arch 1. The baffles 10 are made of steel plates. The bottom of the steel plates is welded to the steel arch 1. Tie rods are used to tie the steel plates on both sides. The tie rods can be made of steel bars with a diameter of 22 mm. Arrange and tie steel bars on the steel arch 1, and then pour concrete to form a concrete arch 2.
[0068] S3: Filling construction is performed using ceramsite concrete to fill the filling area 3. During the filling process, several PVC pipes with a diameter of 110 mm are placed in the filling area 3. The axial direction of the PVC pipe is consistent with the arch width direction of the steel arch 1. The ceramsite concrete is filled to a level with the top of the concrete arch 2 to form a tunnel foundation. At the same time, embedded parts that can be connected to the corrugated steel protective arch 7 are constructed on the tunnel foundation.
[0069] S4: The corrugated steel protective arch 7 is hoisted section by section at the edge of the cave 6 and assembled, the assembled corrugated steel protective arch 7 is hoisted onto the tunnel foundation, and the corrugated steel protective arch 7 is connected to the embedded parts on the tunnel foundation with bolts.
[0070] S5: Fix the buffer layer 8 to the inner side of the corrugated steel protective arch 7 by bolts. The buffer layer 8 is specifically made of rubber blocks. The corrugated steel protective arch 7 and the rubber blocks are both pre-reserved with corresponding screw holes for easy and quick installation.
[0071] S6: constructing the tunnel inner lining 9 on the inner side of the buffer layer 8. The tunnel inner lining 9 is a reinforced concrete structure. The buffer layer 8 is used as an outer mold when pouring the tunnel inner lining 9 to complete the construction.
[0072] The tunnel structure across the cave and the construction method thereof provided by the present invention also have the following advantages:
[0073] The corrugated steel plate is used as the main structure of the steel arch 1, which achieves the effect of quickly crossing the cave 6, making the arch bridge structure construction more convenient, shortening the construction period and reducing safety risks.
[0074] It eliminates the need for large-scale mechanical equipment and the construction of a large-scale lower formwork support system, thus achieving a cost-saving effect.
[0075] The original drainage channel of the cave 6 below is retained to avoid erosion of the tunnel structure by the water flow of the cave 6, thus achieving a durability effect.
[0076] 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 tunnel support structure across a karst cave, characterized in that: include A steel arch (1), wherein the arch foot of the steel arch (1) is connected to the wall of the cave (6), the steel arch (1) is located below the tunnel, the steel arch (1) is an arched corrugated steel plate, the corrugated steel plate has a corrugated cross section, the corrugation extending direction on the cross section is the width direction of the corrugated steel plate, the direction perpendicular to the corrugation extending direction is the length direction of the corrugated steel plate, the corrugated steel plate is bent into an arch along the length direction, and the width direction of the corrugated steel plate is consistent with the width direction of the tunnel; A concrete arch (2), wherein the concrete arch (2) is arranged above the steel arch (1); A filling area (3), wherein the filling area (3) is arranged above the concrete arch (2), and the filling area (3) is used for filling to form a tunnel foundation.
2. A tunnel support structure across a cave according to claim 1, characterized in that: The steel arch (1) comprises a plurality of arch pieces, each of which is an arched corrugated steel plate. The plurality of arch pieces are arranged along the width direction of the corrugated steel plate, and two adjacent arch pieces are connected to each other.
3. A tunnel support structure across a cave according to claim 2, characterized in that: A plurality of the arch pieces are provided with shear nails, and the shear nails are welded to the arch pieces.
4. The tunnel support structure across a karst cave according to claim 1, characterized in that: Baffles (10) are provided on both sides of the steel arch (1), and the baffles (10) on both sides are provided with anti-deformation components.
5. The tunnel support structure across a karst cave according to claim 1, characterized in that: A groove (5) is provided on the wall of the karst cave (6), and the arch foot of the steel arch (1) is connected to the groove (5).
6. The tunnel support structure across a karst cave according to claim 1, characterized in that: The filler area (3) is provided with a hollow structure (4).
7. A tunnel structure across a cave, characterized in that: The invention comprises a protective structure, wherein the protective structure is located above a tunnel support structure across a karst cave as described in any one of claims 1 to 6, wherein the protective structure comprises a corrugated steel protective arch (7), a buffer layer (8) and a tunnel inner lining (9), wherein the bottom of the corrugated steel protective arch (7) is connected to the tunnel support structure, the buffer layer (8) is arranged on the inner side of the corrugated steel protective arch (7), and the tunnel inner lining (9) is arranged on the inner side of the buffer layer (8).
8. A tunnel structure across a karst cave according to claim 7, characterized in that: The buffer layer (8) is a rubber block or a foam plastic block.
9. A tunnel structure across a karst cave according to claim 8, characterized in that: The buffer layer (8) is fixed to the corrugated steel protective arch (7) by means of bolts.
10. The tunnel structure across a karst cave according to claim 7, characterized in that: The inner lining (9) of the tunnel is a reinforced concrete structure, and the thickness of the reinforced concrete structure is 300mm-600mm.
11. A method for constructing a tunnel structure across a karst cave, characterized in that: A tunnel structure across a cave as described in any one of claims 7 to 10, comprising the following steps: S1: using a truck crane to hoist a steel arch (1) that needs to span a karst cave (6) to a designated installation position of the karst cave (6), and installing the arch foot of the steel arch (1) on the wall of the karst cave (6); S2: Arranging and tying steel bars on the steel arch (1), and then pouring concrete to form a concrete arch (2); S3: Carry out filling construction on the filling area (3) and fill it to a predetermined elevation to form a tunnel foundation; S4: hoisting the corrugated steel protection arch (7) onto the tunnel foundation, and fixing the corrugated steel protection arch (7) to the tunnel foundation; S5: fixing the buffer layer (8) to the inner side of the corrugated steel protective arch (7) by means of bolts; S6: Using the buffer layer (8) as a template, constructing the tunnel inner lining (9) on the inner side of the buffer layer (8), thereby completing the construction.