Underground karst landform diversion tunnel top arch hole repairing structure

Abstract

The utility model relates to the technical field of water conservancy and hydropower engineering tunnel repairing, and discloses an underground karst landform diversion tunnel top arch hole repairing structure. Comprising a diversion tunnel and a feeding pipe. Cavities are formed in the tops of the diversion holes; the feeding pipe is pre-buried in the cavity, one end of the feeding pipe is exposed out of the water diversion hole, concrete enters the cavity through the feeding pipe so as to pour the hole in the cavity, and a plugging body is formed on the concrete in the hole and used for repairing the hole. By means of the mode of pre-burying the feeding pipe, concrete can be directly conveyed to the position of the hole in the cavity. Complicated concrete operation does not need to be carried out in a narrow space of the top arch, and the difficulty caused by insufficient construction space is avoided.

Description

Technical Field

[0001] This utility model relates to the field of tunnel repair technology in water conservancy and hydropower engineering, and in particular to a repair structure for the arch hole of a water diversion tunnel in underground karst landforms. Background Technology

[0002] Southwest my country is rich in water resources and has seen the construction of numerous water conservancy and hydropower projects. However, the region also features many karst landforms. Karst landforms are considered unfavorable geological phenomena, and underground karst landforms mainly include caves, underground cavities, and subterranean rivers, exhibiting complex structural conditions. As a major structure in these projects, the water diversion tunnel is prone to arch collapse under these geological conditions, forming voids that affect tunnel stability and pose significant safety hazards.

[0003] Water diversion tunnels located in underground karst areas are prone to developing numerous cavities, caves, and underground rivers. These tunnels are generally pressurized, with structural stress primarily controlled by internal water pressure. Under normal conditions, reinforced concrete is used for secondary lining after tunnel excavation and primary support. However, in these geological conditions, it is difficult to achieve dense backfilling and grouting. The exposed cavities at the top arch are lined as pressurized open-cut tunnels. The concrete in this area is a thin-shell structure, making it difficult to guarantee strength during construction. Under high water pressure, the top arch is prone to collapse, forming voids, which significantly impacts the safe operation of the water diversion tunnel.

[0004] Currently, the cavities in the underground karst water diversion tunnel are divided into two categories: small cavities within the cavities are backfilled with concrete to make them dense, while large cavities are repaired by pouring concrete at the cavity location; due to limited construction conditions, the concrete at the top arch cannot be leveled or vibrated, and conventional pouring techniques cannot be used under these conditions. Utility Model Content

[0005] This utility model aims to provide a repair structure for the arch hole in the top of an underground karst landform water diversion tunnel, in order to solve the technical problems proposed in the prior art.

[0006] The technical problem solved by this utility model embodiment is addressed by the following technical solution:

[0007] A repair structure for the arched cavity in the roof of an underground karst landform water diversion tunnel is provided, comprising:

[0008] A water diversion tunnel, the top of which is provided with a cavity;

[0009] A feed pipe is embedded in the cavity, with one end of the feed pipe exposed in the water inlet. Concrete enters the cavity through the feed pipe and pours concrete into the holes in the cavity. The concrete in the holes forms a sealing body, which is used to repair the holes.

[0010] In some embodiments, the concrete is self-compacting concrete.

[0011] In some embodiments, a mortar anchor is also included, which is connected to the sealing body within the hole.

[0012] In some embodiments, a reinforcing mesh is also included, which is disposed within the cavity and connected to the sealing body.

[0013] In some embodiments, the mortar anchor is connected to the steel mesh to enhance the connection strength of the mortar anchor.

[0014] In some embodiments, multiple feed pipes are provided, and the multiple feed pipes are distributed at intervals within the cavity.

[0015] Compared with existing technologies, the underground karst landform water diversion tunnel arch cavity repair structure provided in this embodiment includes a water diversion tunnel and a feed pipe. A cavity is provided at the top of the water diversion tunnel; the feed pipe is pre-embedded in the cavity, with one end exposed above the water diversion tunnel. Concrete enters the cavity through the feed pipe and pours concrete into the cavity to repair the cavities. The concrete on the cavities forms a sealing body, which is used to repair the cavities. By pre-embedding the feed pipe, concrete can be directly delivered to the cavities within the cavity. Complex concrete operations are not required within the narrow space of the arch, avoiding difficulties caused by insufficient construction space. Attached Figure Description

[0016] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0017] Figure 1 This is a transverse sectional view of the arch hole repair structure of the underground karst landform water diversion tunnel provided in one embodiment of the present invention;

[0018] Figure 2 This is a longitudinal sectional view of the underground karst landform water diversion tunnel arch hole repair structure provided in one embodiment of this utility model.

[0019] Figure label:

[0020] 100. Repair structure of the arch hole in the top of the water diversion tunnel in underground karst landform; 10. Water diversion tunnel; 20. Feed pipe; 30. Cavity; 40. Mortar anchor; 50. Steel mesh; 60. Concrete. Detailed Implementation

[0021] To facilitate understanding of this utility model, a more detailed description is provided below with reference to the accompanying drawings and specific embodiments. It should be noted that when an element is described as "connected" to another element, it can be directly on the other element, or one or more intermediate elements may exist between them. The terms "upper," "lower," "left," "right," "upper end," "lower end," "top," and "bottom," etc., used in this specification, indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0022] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention.

[0023] The following is combined with Figure 1 and Figure 2 The present application provides a detailed description of the underground karst landform water diversion tunnel arch hole repair structure through specific embodiments.

[0024] Please see Figure 1 and Figure 2 , Figure 1 This is a transverse sectional view of the arch hole repair structure of the underground karst landform water diversion tunnel provided in one embodiment of the present invention; Figure 2 This is a longitudinal sectional view of the underground karst landform water diversion tunnel arch hole repair structure provided in one embodiment of the present invention. The underground karst landform water diversion tunnel arch hole repair structure 100 provided in one embodiment of the present invention includes a water diversion tunnel 10 and a feed pipe 20. A cavity 30 is provided at the top of the water diversion tunnel 10; the feed pipe 20 is pre-embedded in the cavity 30, with one end of the feed pipe 20 exposed above the water diversion tunnel 10. Concrete 60 enters the cavity 30 through the feed pipe 20 to pour concrete into the hole in the cavity 30. The concrete 60 on the hole forms a sealing body, which is used to repair the hole.

[0025] In the restoration of the arch of the water diversion tunnel 10 in karst topography, conventional concrete pouring techniques (such as leveling and vibration) were difficult to implement due to limited construction space at the arch location. However, this method, which uses pre-embedded feed pipes 20, allows concrete to be directly delivered to the holes within the cavity 30. This eliminates the need for complex concrete pouring operations within the narrow space of the arch, avoiding the difficulties caused by insufficient construction space.

[0026] For example, in the repair project of the arch of the water diversion tunnel 10 in some underground karst areas, the arch is high above the ground, making it difficult for construction personnel and equipment to reach the appropriate position for conventional pouring. The setting of the feed pipe 20 is like a "transport channel", which allows the concrete 60 to accurately reach the hole that needs to be repaired, greatly improving the operability of the construction.

[0027] Concrete 60 enters the cavity 30 through the feed pipe 20, forming a seal at the cavity location. This seal effectively fills the cavity, enhancing the structural integrity of the arch. Because cavities in the arch of the water diversion tunnel 10 in karst topography affect the tunnel's stability, this repair structure allows for precise repair of these cavities, making the arch more stable under the influence of internal water pressure. For example, during normal operation of the water diversion tunnel 10, internal water pressure exerts pressure on the arch. If cavities exist in the arch, further damage can easily occur under this pressure. The seal formed by the concrete 60 injected through the feed pipe 20 resists water pressure, preventing the arch from collapsing due to the cavities and ensuring the safe operation of the water diversion tunnel 10. This repair structure operates within the cavity 30, eliminating the need for large-scale modifications to the main structure of the water diversion tunnel 10. The feed pipe 20 is pre-embedded within the cavity 30, minimizing damage to the original structure of the water diversion tunnel 10 compared to other repair methods (such as large-scale demolition and reconstruction of the arch).

[0028] In some embodiments, concrete 60 is self-compacting concrete. Self-compacting concrete has excellent flowability, and when it enters the cavities within the cavity 30 through the feed pipe 20, it can automatically fill every corner of the cavity without the need for vibration. This is because self-compacting concrete has a reasonable particle size distribution, and the paste can fully coat the aggregate, allowing it to flow like a liquid and fill complex-shaped cavities under its own weight. For example, in the complex cavity structure of the arch of the karst topwater tunnel 10, there may be some narrow gaps or irregularly shaped cavities 30. Ordinary concrete may not be able to completely fill these gaps, leaving voids, while self-compacting concrete, with its good flowability, can fill these gaps and irregular cavities 30, ensuring a denser repaired structure.

[0029] Self-compacting concrete is a type of concrete characterized by high fluidity, non-segregation, uniformity, and good stability. It can fill all corners of the formwork under its own weight without vibration, forming a dense concrete structure. It should be noted that this self-compacting concrete is a commercially available type of concrete.

[0030] In some embodiments, mortar anchors 40 are also included, which are connected to the sealing body inside the borehole. The mortar anchors 40 can more tightly connect the sealing body to the surrounding rock mass. In karst landforms, the properties of the rock mass are complex, and the arch of the water diversion tunnel 10 bears various loads such as internal water pressure. Through the connection of the mortar anchors 40, the sealing body no longer bears the pressure alone, but can transfer some of the pressure to the surrounding rock mass. For example, when there is high water pressure inside the water diversion tunnel 10 acting on the sealing body of the arch, the mortar anchors 40 act like "anchor claws," holding the sealing body in place while dispersing the pressure to the surrounding rock mass. This effectively prevents the sealing body from partially detaching or shifting under loads such as water pressure, greatly enhancing the overall stability of the repair structure.

[0031] In some embodiments, a reinforcing mesh 50 is also included, which is disposed within the cavity 30 and connected to the sealing body. In the working environment of the karst top arch of the water diversion tunnel 10, the sealing body may be subjected to forces in various directions, especially when subjected to pressure from above, making it prone to bending deformation. The reinforcing mesh 50 effectively enhances the bending resistance of the sealing body. When the sealing body is subjected to vertical pressure, the transverse reinforcing bars in the reinforcing mesh 50 can resist bending like a beam. For example, assuming the sealing body is a thin plate structure, under pressure, the middle section tends to bend downwards. The reinforcing bars in the reinforcing mesh 50 generate tensile force, preventing this bending deformation and distributing the pressure more evenly across the sealing body, thereby enhancing the overall bending resistance of the sealing body and preventing cracks or damage due to bending during long-term use.

[0032] Specifically, when self-compacting concrete generates shrinkage stress during its setting process, the reinforcing mesh 50 exerts a reverse restraining force on the concrete 60. This restraining force can inhibit the shrinkage of the concrete 60, thereby reducing the likelihood of cracks appearing. Moreover, once a small crack appears in the sealing structure, the reinforcing mesh 50 can also prevent the crack from propagating further. Because the crack is hindered by the reinforcing mesh during its extension, the presence of the reinforcing mesh makes it difficult for the crack to penetrate the entire sealing structure, thus improving the crack resistance of the sealing structure.

[0033] In some embodiments, the mortar anchor 40 is connected to the steel mesh 50 to enhance the connection strength of the mortar anchor 40. After the mortar anchor 40 and the steel mesh 50 are connected, they can work together to further improve the stability of the entire karst top arch repair structure of the water diversion tunnel 10. The mortar anchor 40 is mainly responsible for anchoring the sealing body to the surrounding rock mass and transmitting and distributing the load; while the steel mesh 50 can enhance the integrity and strength of the sealing body itself. After they are connected to each other, they form a more stable "force network", which enables the repaired top arch to better resist various forces generated by internal water pressure, rock self-weight, and possible external geological changes, effectively reducing the risk of the top arch being damaged again. For example, in the face of complex and changeable karst geological environments, such as groundwater level fluctuations and slight displacement of surrounding rock masses, this connection structure can ensure that the repaired part of the top arch remains stable and ensure the safe operation of the water diversion tunnel 10.

[0034] In some embodiments, multiple feed pipes 20 are provided, and the multiple feed pipes 20 are distributed at intervals within the cavity 30. The shape and size of the holes in the arch of the karst landform water diversion tunnel 10 are often irregular, and a single feed pipe 20 may not be able to uniformly fill the entire hole area with concrete 60. Multiple feed pipes 20 distributed at intervals can deliver self-compacting concrete into the holes within the cavity 30 from different positions, which can better cover the entire hole space and avoid local incomplete filling.

[0035] It should be noted that the underground karst landform water diversion tunnel arch hole repair structure 100 provided in this utility model embodiment only shows the part related to the technical problem to be solved by this utility model embodiment. It can be understood that the underground karst landform water diversion tunnel arch hole repair structure 100 provided in this utility model embodiment also includes other structures for realizing the function of the underground karst landform water diversion tunnel arch hole repair structure 100, which will not be described in detail again.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it; under the concept of this utility model, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of this utility model as described above. For the sake of brevity, they are not provided in detail; although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.

Claims

1. A repair structure for the arched opening in the roof of an underground karst landform water diversion tunnel, characterized in that, include: A water diversion tunnel, the top of which is provided with a cavity; A feed pipe is embedded in the cavity, with one end of the feed pipe exposed in the water inlet. Concrete enters the cavity through the feed pipe and pours concrete into the holes in the cavity. The concrete in the holes forms a sealing body, which is used to repair the holes.

2. The structure for repairing the arched opening in the roof of an underground karst landform water diversion tunnel according to claim 1, characterized in that, The concrete is self-compacting concrete.

3. The structure for repairing the arched opening in the roof of an underground karst landform water diversion tunnel according to claim 2, characterized in that, It also includes mortar anchors, which are connected to the sealing body inside the hole.

4. The structure for repairing the arched opening in the roof of an underground karst landform water diversion tunnel according to claim 3, characterized in that, It also includes a steel mesh, which is disposed within the cavity shown and connected to the sealing body.

5. The structure for repairing the arched opening of an underground karst landform water diversion tunnel according to claim 4, characterized in that, The mortar anchor is connected to the steel mesh to enhance the connection strength of the mortar anchor.

6. The structure for repairing the arched opening in the roof of an underground karst landform water diversion tunnel according to claim 5, characterized in that, The feed pipes are provided in multiple ways, and the multiple feed pipes are distributed at intervals within the cavity.

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