Small-spacing tunnel interlayer rock reinforcing method and structure and tunnel construction method
By applying a large pipe shed to form an advanced pre-supported structure before excavation of the tunnel, the problems of long construction period of traditional reinforcement methods and large disturbances of the centered rock are solved, and the construction safety and progress are improved.
Patent Information
- Application Number
- CN202411444449.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-16
- Publication Date
- 2025-02-18
AI Technical Summary
The traditional rock clamping reinforcement method in small-pitch tunnels has problems such as long construction period, cumbersome processes, large disturbances in the rock clamping, and increasing construction risks.
Before excavation of the tunnel, the first large pipe shed, the second large pipe shed and the third large pipe shed are built to form an advanced pre-supported structure to withstand the pressure of the surrounding rock in advance and reduce the load and disturbance of the middle clamped rock.
Through advance reinforcement, the settlement of surrounding rocks and unstable collapse of middle-clad rocks can be effectively restricted, construction safety and progress can be improved, and the risk of tunnel collapse is reduced.
Smart Images
Figure CN119466812A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of tunnel engineering, and in particular to a rock reinforcement method and structure in a small-spacing tunnel, and a tunnel construction method. Background Art
[0002] In tunnel engineering, the spacing of tunnels has an important impact on the stability and safety of tunnels. When the spacing between tunnels is small, especially when the clear distance is less than 6 meters, the stability of the rock between tunnels becomes the key point for the success of tunnel design and construction. Therefore, in order to ensure the safety and stability of the tunnel, effective reinforcement of the rock between tunnels is required.
[0003] Traditional methods for reinforcing interlayer rock in small-spacing tunnels mainly include small-duct grouting, system anchors, and tension prestressed anchors. Although these reinforcement methods can improve the stability of interlayer rock in small-spacing tunnels to a certain extent, they have the following shortcomings in practical applications:
[0004] 1. Traditional reinforcement methods are usually carried out after the surrounding rock is excavated. The process is cumbersome and the construction period is long. The surrounding rock cannot be quickly sealed. In addition, the interlayer rock will be disturbed during the excavation process, which may cause damage to the interlayer rock and lead to unstable collapse of the interlayer rock, increasing the construction risk and uncertainty of the construction progress.
[0005] 2. Traditional reinforcement methods require sophisticated mechanical equipment and highly skilled operators. The construction is difficult and it is difficult to ensure that the ideal reinforcement effect can be achieved every time. If the mechanical operation is improper or the equipment accuracy is insufficient, it may increase the disturbance of the central rock and increase the risk of tunnel collapse. Summary of the invention
[0006] The purpose of the present application is to provide a method, structure and tunnel construction method for reinforcing rock in small-spacing tunnels, so as to solve the problem that existing reinforcement methods increase the risk of rock-interposed construction.
[0007] The technical solution adopted by this application to solve its technical problem is:
[0008] In a first aspect, a method for reinforcing interbedded rock in closely spaced tunnels is provided, comprising: before excavating a first tunnel and a second tunnel, constructing a first large pipe shed in the surrounding rock at the top of the first tunnel, constructing a second large pipe shed in the surrounding rock at the top of the second tunnel, and constructing a third large pipe shed in the surrounding rock at the top of the interbedded rock between the first tunnel and the second tunnel.
[0009] Furthermore, the arrangement range of the first large pipe shelf is from the spandrel on the side away from the middle rock to the spandrel on the side close to the middle rock.
[0010] Furthermore, the arrangement range of the second large pipe shelf is from the spandrel on the side away from the middle rock to the spandrel on the side close to the middle rock.
[0011] Furthermore, the arrangement range of the third large pipe rack is from the spandrel close to one side of the first tunnel to the spandrel close to one side of the second tunnel.
[0012] Furthermore, the construction method of the third large pipe rack includes: constructing an operating platform at a position facing the middle rock, fixing a plurality of third guide tubes extending toward the middle rock on the operating platform; using the third guide tubes for guidance and drilling holes in the surrounding rock at the top of the middle rock to form a third pipe rack installation hole; inserting a third steel pipe into the third pipe rack installation hole, the wall of the third steel pipe having grouting holes, installing a steel cage in the third steel pipe and grouting.
[0013] Furthermore, the operating platform includes a first set of arch steel frames arranged opposite to the first tunnel, a second set of arch steel frames arranged opposite to the second tunnel, and a plurality of cross beams fixed between the first set of arch steel frames and the second set of arch steel frames; the third guide tube is fixed on the cross beams.
[0014] Furthermore, the length of the third steel pipe is 30 to 40 m.
[0015] Furthermore, the third steel pipe includes a plurality of detachably connected sections.
[0016] In a second aspect, a rock reinforcement structure for closely spaced tunnels is provided, comprising a first large pipe shed arranged in the surrounding rock at the top of a first tunnel, a second large pipe shed arranged in the surrounding rock at the top of a second tunnel, and a third large pipe shed arranged in the surrounding rock at the top of the intermediate rock between the first tunnel and the second tunnel.
[0017] On the third aspect, a tunnel construction method is provided, comprising: firstly adopting the method for reinforcing the interlayer rock in a small-spacing tunnel provided by the first aspect to pre-support the first tunnel, the second tunnel and the interlayer rock; then excavating the first tunnel in sections and segments, and completing the secondary lining of the first tunnel; then excavating the second tunnel in sections and segments, and completing the secondary lining of the second tunnel.
[0018] Beneficial effects of this application:
[0019] The method for reinforcing the interlayer rock in a small-spacing tunnel provided in the embodiment of the present application is carried out before tunnel excavation. By constructing a first large pipe shed, a second large pipe shed and a third large pipe shed, an advanced pre-support structure is formed on the top of the first tunnel, the second tunnel and the interlayer rock. The advanced pre-support structure is used to bear the surrounding rock pressure in advance and effectively limit the settlement of the surrounding rock. In the later tunnel excavation process, the load borne by the interlayer rock and the disturbance to the interlayer rock are greatly reduced, and unstable collapse of the interlayer rock is avoided, thereby improving construction safety and ensuring construction progress. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.
[0021] Figure 1 is a schematic diagram of a rock reinforcement structure in a small-spacing tunnel provided in an embodiment of the present application;
[0022] Figure 2 This is a schematic diagram of the structure when the third largest pipe shed was being constructed.
[0023] Reference numerals:
[0024] 10- First tunnel;
[0025] 11-The first pipe shed;
[0026] 20-Second tunnel;
[0027] 21-The second largest pipe shed
[0028] 30-middle intercalated rock;
[0029] 31- The third largest pipe shed;
[0030] 40- third guide tube;
[0031] 50-third steel pipe;
[0032] 60-the first set of arch steel frames;
[0033] 70-Second set of arch steel frame;
[0034] 80- beam. DETAILED DESCRIPTION
[0035] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application.
[0036] It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings. In addition, the embodiments and features in the embodiments of this application can be combined with each other without conflict.
[0037] In the description of the embodiments of the present application, the indicated orientation or positional relationship is based on the orientation or positional relationship shown in the accompanying drawings, or is the orientation or positional relationship in which the product of the application is usually placed when in use, or is the orientation or positional relationship commonly understood by those skilled in the art. The terms "disposed", "opened", "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, and an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal connection of two elements.
[0038] See also Figure 1 The first tunnel 10 and the second tunnel 20 are arranged side by side with a small distance between them. When the net distance between them is less than 6 meters, the stability of the middle rock 30 between the first tunnel 10 and the second tunnel 20 becomes the key point for the successful design and construction of the tunnel. In order to ensure the safety and stability of the tunnel, the middle rock needs to be effectively reinforced.
[0039] A method for reinforcing interlayer rock in a small-spacing tunnel provided in an embodiment of the present application comprises the following steps: before excavating the first tunnel 10 and the second tunnel 20, a first large pipe shed 11 is constructed in the surrounding rock at the top of the first tunnel 10, a second large pipe shed 21 is constructed in the surrounding rock at the top of the second tunnel 20, and a third large pipe shed 31 is constructed in the surrounding rock at the top of the intermediate rock 30 between the first tunnel 10 and the second tunnel 20.
[0040] The method for reinforcing the interlayer rock in a small-spacing tunnel provided in the embodiment of the present application is carried out before tunnel excavation, and the first large pipe shed 11 is used to pre-support the surrounding rock at the top of the first tunnel 10, the second large pipe shed 21 is used to pre-support the surrounding rock at the top of the second tunnel 20, and the third large pipe shed 31 is used to pre-support the surrounding rock at the top of the interlayer rock 30. Thus, an advance pre-support structure can be formed at the top of the first tunnel 10, the second tunnel 20 and the interlayer rock 30 by the first large pipe shed 11, the second large pipe shed 21 and the third large pipe shed 31. The advance pre-support structure is used to bear the surrounding rock pressure in advance, and the settlement, loosening and collapse of the surrounding rock are effectively restricted. In the later tunnel excavation process, the load borne by the interlayer rock 30 and the disturbance to the interlayer rock 30 are greatly reduced, and the unstable collapse of the interlayer rock 30 is avoided, thereby improving the construction safety and ensuring the construction progress. Compared with traditional reinforcement methods, this application does not require grouting reinforcement of the middle rock after tunnel excavation, which saves construction procedures, avoids increased disturbance to the middle rock due to improper mechanical operation or insufficient equipment accuracy, and greatly reduces the risk of tunnel collapse.
[0041] In some embodiments, see Figure 1 , the arrangement range of the first large pipe shed 11 is from the spandrel on the side away from the middle interlayer rock 30 to the spandrel on the side close to the middle interlayer rock 30. Exemplarily, the first large pipe shed 11 is an overall arc-shaped structure at the top of the first tunnel 10. The arrangement range of the second large pipe shed 21 is from the spandrel on the side away from the middle interlayer rock 30 to the spandrel on the side close to the middle interlayer rock 30. Exemplarily, the second large pipe shed 21 is an overall arc-shaped structure at the top of the second tunnel 20. The arrangement range of the third large pipe shed 31 is from the spandrel on the side close to the first tunnel 10 to the spandrel on the side close to the second tunnel 20. Exemplarily, the third large pipe shed 31 is an overall linear structure at the top of the middle interlayer rock 30.
[0042] In some embodiments, see Figure 2The construction method of the third large pipe rack 31 includes the following steps: constructing an operating platform at a position directly opposite to the middle rock 30, fixing a plurality of third guide pipes 40 extending toward the middle rock 30 on the operating platform; using the third guide pipes 40 for guidance and drilling holes in the surrounding rock at the top of the middle rock 30 to form a third pipe rack installation hole; inserting a third steel pipe 50 into the third pipe rack installation hole, the wall of the third steel pipe 50 having a grouting hole, installing a steel cage in the third steel pipe 50 and grouting. An operating platform is provided to support personnel, tools and drilling tools, so that the operator can perform drilling operations. A third guide pipe 40 is provided to guide the drilling holes on the intermediate rock 30, which not only reduces the difficulty of drilling but also improves the accuracy of drilling. The third steel pipe 50 is inserted into the third pipe rack installation hole, and a steel cage and grouting are installed in the third steel pipe 50. The steel cage and slurry are used to improve the bearing capacity and stability of the third steel pipe 50. The grouting slurry is pressed into the cracks of the surrounding rock through the grouting holes of the third steel pipe 50 to cement and consolidate the loose rock mass, thereby improving the physical and mechanical properties of the surrounding rock, enhancing the self-bearing capacity of the surrounding rock, and achieving the purpose of reinforcing the surrounding rock around the third steel pipe 50.
[0043] In some embodiments, see Figure 2 The operating platform includes a first set of arch steel frames 60 arranged facing the first tunnel 10, a second set of arch steel frames 70 arranged facing the second tunnel 20, and a plurality of cross beams 80 fixed between the first set of arch steel frames 60 and the second set of arch steel frames 70; the third guide tube 40 is fixed on the cross beams 80. Exemplarily, both ends of the cross beams 80 are respectively welded to the first set of arch steel frames 60 and the second set of arch steel frames 70, and connecting steel bars are welded between two adjacent cross beams 80. The cross beams 80 can be made of I-beams.
[0044] In some embodiments, the third steel pipe 50 includes a steel pipe of φ108×6mm, and the length of the third steel pipe 50 is 30-40m; the third guide pipe 40 includes a steel pipe of φ127×6mm, and the length of the third guide pipe 40 is 2-3m. In order to facilitate the installation and transportation of the third steel pipe 50, the third steel pipe 50 includes multiple sections that can be detachably connected, each section of the third steel pipe 50 is 5m long, and two adjacent sections of the third steel pipe 50 are connected by a threaded pipe of φ102×6mm.
[0045] See also Figure 1 The embodiment of the present application also provides a rock reinforcement structure in a small-spacing tunnel, including a first large pipe shelf 11 arranged in the top surrounding rock of a first tunnel 10, a second large pipe shelf 21 arranged in the top surrounding rock of a second tunnel 20, and a third large pipe shelf 31 arranged in the top surrounding rock of a middle rock 30 between the first tunnel 10 and the second tunnel 20.
[0046] Exemplarily, the first large pipe shelf 11 is an overall arc-shaped structure at the top of the first tunnel 10, and the arrangement range of the first large pipe shelf 11 is from the arch shoulder on the side away from the middle rock 30 to the arch shoulder on the side close to the middle rock 30; the second large pipe shelf 21 is an overall arc-shaped structure at the top of the second tunnel 20, and the arrangement range of the second large pipe shelf 21 is from the arch shoulder on the side away from the middle rock 30 to the arch shoulder on the side close to the middle rock 30; the third large pipe shelf 31 is an overall linear structure at the top of the middle rock 30, and the arrangement range of the third large pipe shelf 31 is from the arch shoulder on the side close to the first tunnel 10 to the arch shoulder on the side close to the second tunnel 20.
[0047] The embodiment of the present application also provides a rock reinforcement structure in a small-spacing tunnel, which can be constructed before tunnel excavation to form an advanced pre-support structure. The advanced pre-support structure is used to withstand the surrounding rock pressure in advance, effectively limiting the settlement, loosening and collapse of the surrounding rock. In the later tunnel excavation process, the load borne by the middle rock 30 and the disturbance to the middle rock 30 are greatly reduced, and unstable collapse of the middle rock 30 is avoided, thereby improving construction safety and ensuring construction progress.
[0048] The embodiment of the present application also provides a tunnel construction method, comprising: firstly adopting the small-spacing tunnel interlayer rock reinforcement method provided in the above embodiment to perform advance pre-support on the first tunnel 10, the second tunnel 20 and the interlayer rock 30; then excavating the first tunnel 10 in sections and segments, and completing the secondary lining of the first tunnel 10; then excavating the second tunnel 20 in sections and segments, and completing the secondary lining of the second tunnel 20.
[0049] The embodiment of the present application also provides a tunnel construction method. Since the first tunnel 10, the second tunnel 20 and the middle interlayer rock 30 are reinforced in advance to form an advanced pre-support structure, the advanced pre-support structure is used to bear the surrounding rock pressure in advance, effectively limiting the settlement, loosening and collapse of the surrounding rock. In the later tunnel excavation process, the load borne by the middle interlayer rock 30 and the disturbance to the middle interlayer rock 30 are greatly reduced, and the unstable collapse of the middle interlayer rock 30 is avoided, thereby improving the construction safety and ensuring the construction progress.
[0050] The above is only a preferred embodiment of the present application and does not constitute any form of limitation to the present application. Based on the technical essence of the present application and within the spirit and principles of the present application, any simple modification, equivalent replacement and improvement of the above embodiments shall still fall within the protection scope of the technical solution of the present application.
Claims
1. A method for reinforcing rock in a small-spacing tunnel, characterized in that: include: Before the excavation of the first tunnel (10) and the second tunnel (20), a first large pipe shed (11) is constructed in the surrounding rock at the top of the first tunnel (10), a second large pipe shed (21) is constructed in the surrounding rock at the top of the second tunnel (20), and a third large pipe shed (31) is constructed in the surrounding rock at the top of the intermediate rock (30) between the first tunnel (10) and the second tunnel (20).
2. The rock reinforcement method in a small-spacing tunnel according to claim 1 is characterized in that: The arrangement range of the first large pipe shelf (11) is from the spandrel on the side away from the middle interlayer rock (30) to the spandrel on the side close to the middle interlayer rock (30).
3. The rock reinforcement method in a small-spacing tunnel according to claim 1 is characterized in that: The arrangement range of the second large pipe shelf (21) is from the spandrel on the side away from the middle interlayer rock (30) to the spandrel on the side close to the middle interlayer rock (30).
4. The rock reinforcement method in a small-spacing tunnel according to claim 1, 2 or 3, characterized in that: The third large pipe rack (31) is arranged from the spandrel close to the first tunnel (10) to the spandrel close to the second tunnel (20).
5. The rock reinforcement method in a small-spacing tunnel according to claim 1 is characterized in that: The construction method of the third large pipe rack (31) comprises: An operating platform is constructed at a position facing the middle rock (30), and a plurality of third guide pipes (40) extending toward the middle rock (30) are fixed on the operating platform; Using the third guide pipe (40) for guidance, and drilling a hole in the surrounding rock at the top of the middle rock (30) to form a third pipe shelf installation hole; A third steel pipe (50) is inserted into the third pipe rack installation hole, a grouting hole is provided on the wall of the third steel pipe (50), and a steel cage is installed in the third steel pipe (50) and grouting is performed.
6. The rock reinforcement method in a small-spacing tunnel according to claim 5 is characterized in that: The operating platform comprises a first set of arch steel frames (60) arranged opposite to the first tunnel (10), a second set of arch steel frames (70) arranged opposite to the second tunnel (20), and a plurality of cross beams (80) fixed between the first set of arch steel frames (60) and the second set of arch steel frames (70); the third guide tube (40) is fixed on the cross beams (80).
7. The rock reinforcement method in a small-spacing tunnel according to claim 5 is characterized in that: The length of the third steel pipe (50) is 30 to 40 m.
8. The rock reinforcement method in a small-spacing tunnel according to claim 7 is characterized in that: The third steel pipe (50) comprises a plurality of detachably connected sections.
9. A rock reinforcement structure in a small-spacing tunnel, characterized in that: The invention comprises a first large pipe shelf (11) arranged in the surrounding rock at the top of a first tunnel (10), a second large pipe shelf (21) arranged in the surrounding rock at the top of a second tunnel (20), and a third large pipe shelf (31) arranged in the surrounding rock at the top of an intermediate rock (30) between the first tunnel (10) and the second tunnel (20).
10. A tunnel construction method, characterized in that: include: First, the method for reinforcing the interlayer rock in a small-spacing tunnel as described in any one of claims 1 to 8 is used to perform advance pre-support on the first tunnel (10), the second tunnel (20) and the interlayer rock (30); then, the first tunnel (10) is excavated in sections and segments, and the secondary lining of the first tunnel (10) is completed; then, the second tunnel (20) is excavated in sections and segments, and the secondary lining of the second tunnel (20) is completed.