A composite flexible structure against stick-slip dislocation for crossing large active fault tunnel

Abstract

This invention relates to the field of water conservancy and hydropower engineering construction technology, and discloses a composite toughness structure for resisting adhesion and slippage in tunnels traversing large active faults. The structure includes a tunnel widening section, which is connected to a normal tunnel section via a tunnel transition section. The inner side of the widened tunnel section is provided with shotcrete and anchor initial support, and the inner side of the shotcrete and anchor initial support is provided with a lining. The lining adopts a "short lining, wide joint" double-layer concrete lining with a foamed concrete isolation and energy dissipation layer in between. A consolidation grouting ring is provided on the outer side of the lining. A pressure steel pipe is installed inside the lining, with seismic bearings at the bottom of the pressure steel pipe and seismic dampers on both sides of the pressure steel pipe. This invention can improve the tunnel's resistance to slippage, allowing the dynamic effects and energy during active fault vibrations to be dissipated in multiple ways, reducing the energy transmitted to the water conveyance pressure steel pipe, and avoiding disasters such as tunnel surrounding rock damage or water inrush and mudslides caused by large-scale rapid slippage.

Description

Technical Field

[0001] This invention relates to the field of water conservancy and hydropower engineering construction technology, and in particular to a composite toughness structure for resisting adhesion and slippage through large active fracture tunnels. Background Technology

[0002] Many large-scale water conservancy and hydropower projects face the challenge of tunneling through large active faults, such as the Dianzhong Water Diversion Project, the Western Route of the South-to-North Water Diversion Project, and subsequent large-scale hydropower projects on international rivers in Southwest China. The displacement and deformation of large active faults have a significant impact on the safe operation of tunnels and are a factor that must be considered in the design.

[0003] Active faults are mostly large-scale regional faults, with fault zones and their affected zones reaching hundreds of meters in width. Stick-slip and creep are two modes of activity for active faults. Creep manifests as continuous, slow displacement of the fault zone in a seismic state. It acts as an inhibitory factor for elastic strain energy and earthquake formation, with an annual displacement rate only on the order of millimeters. However, its effect is significant over the 100-year service life of a project, with cumulative displacement deformation reaching several meters, causing cracking and damage to tunnel lining structures and affecting normal water conveyance. Stick-slip, on the other hand, is a rapid rupture and displacement of the fault during an earthquake. It has a high displacement rate, significant dynamic load effects, and intense instantaneous destructive force. For earthquakes of magnitude 7 or higher, it often causes significant displacement at the surface of the fault, with a single displacement reaching several meters, resulting in enormous destructive force and direct displacement and destruction of buildings and structures crossing the fault zone within a short period.

[0004] Current research and engineering applications on the impact of tunnels crossing large active faults mainly focus on creep faulting. Tunnel fortification aims for "normal operation during service life." Based on the estimated amount of fault creep faulting during service life, engineering measures such as widening excavation, articulation, isolation and energy dissipation, and open pipes inside the tunnel can basically eliminate the impact of fault creep faulting on tunnels. The above measures have been adopted in projects such as the Zhangjiuhe Water Diversion Project, the Niulanjiang-Dianchi Water Replenishment Project, and the Dianzhong Water Diversion Project.

[0005] Currently, there is very little research on the impact of stick-slip slippage on tunnels crossing large active faults and anti-slippage engineering measures, and there are no specific engineering applications. Existing measures cannot adapt to stick-slip slippage during earthquakes of active faults; they can only reduce earthquake damage and then repair or rebuild after the earthquake. The goal of tunnel fortification is to "reduce earthquake damage and allow for repair after the earthquake."

[0006] The proposed large-scale water conservancy and hydropower projects along the western route of the South-to-North Water Diversion Project and some international rivers in Southwest China face the problem of tunnels crossing large active faults. The safety requirements for the operation of these projects are high, and the consequences of disasters would be severe. Considering only creep slippage is not sufficient to meet the needs of safe operation of tunnels under extreme conditions. It is necessary to propose a high-toughness anti-stick-slip slippage structure that can adapt to large slippage deformation, high deformation rate, and instantaneous concentrated energy release, based on the existing anti-slippage structure. Summary of the Invention

[0007] To overcome the above shortcomings, this invention provides a composite toughness structure for resisting stick-slip faulting through large active fault tunnels, aiming to improve the problem that existing measures cannot adapt to stick-slip faulting during active fault earthquakes, can only reduce earthquake damage, and still require repair or reconstruction after the earthquake.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a composite toughness structure for resisting adhesion and slippage through a large active fracture tunnel, comprising a tunnel widening section, the tunnel widening section being connected to a normal tunnel section via a tunnel transition section, the inner side of the tunnel widening section being provided with shotcrete and anchor initial support, the inner side of the shotcrete and anchor initial support being provided with a lining, the lining being a "short lining, wide joint" double-layer concrete lining with a foamed concrete isolation and energy dissipation layer in between, the outer side of the lining being provided with a consolidation grouting ring, a pressure steel pipe being installed inside the lining, a seismic bearing being provided at the bottom of the pressure steel pipe, and seismic dampers being provided on both sides of the pressure steel pipe.

[0009] Preferably, the tunnel widening section includes an active fracture main fracture zone and an active fracture influence zone. The active fracture influence zones are located on both sides of the active fracture main fracture zone, and the active fracture influence zones on both sides are respectively connected to the adjacent sides of the two tunnel transition sections.

[0010] Preferably, the two ends of the active fracture zone are provided with universal corrugated expansion joints connecting pressure steel pipes.

[0011] Preferably, the initial shotcrete support includes a concrete layer and system anchor bolts laid on the inner side of the tunnel widening section.

[0012] Preferably, the lining is a short compartment and a wide joint, forming a hinged structure. The "short lining and wide joint" double-layer concrete lining with a foamed concrete isolation and energy dissipation layer in the middle includes an outer reinforced concrete lining, an intermediate plain foamed concrete interlayer, and an inner reinforced concrete lining connected sequentially from the outside to the inside. The pressure steel pipe is connected to the inner reinforced concrete lining.

[0013] Preferably, the construction method of the anti-stick-slip composite toughness structure includes the following steps:

[0014] When the tunnel passes through a large active fault section, the tunnel is widened in the main fault zone and the influence zone of the active fault to form a tunnel widening section. The widening size is 3m circumferential widening on the basis of the original excavation fault. The tunnel widening section is connected to the normal tunnel section through the tunnel transition section. The total length of the tunnel transition section is 30m.

[0015] After excavation, initial shotcrete and anchor support is installed, which specifically includes spraying 20cm thick concrete and systematically arranging 6m long hollow grouting anchors with a spacing of 1.5 to 3m between the anchors.

[0016] After the initial shotcrete and anchor support is completed, an outer reinforced concrete lining, an intermediate plain foamed concrete interlayer, and an inner reinforced concrete lining are constructed with thicknesses of 0.8m, 0.6m, and 1.2m, respectively. The inner and outer linings adopt a "short lining, wide joint" hinged structure, with a structural joint set every 6m and a joint width of 5cm.

[0017] After the inner reinforced concrete lining is completed, holes are drilled around the tunnel to a depth of 10m. Cement grout is injected into the holes under high pressure to reinforce the surrounding rock and form a consolidation grouting ring.

[0018] After the consolidation grouting is completed, a water supply pressure steel pipe is installed inside the inner reinforced concrete lining. The water supply pressure steel pipe extends 15m into the tunnel transition section.

[0019] Every 10m, seismic bearings and seismic dampers are installed circumferentially on the pressure steel pipe; the seismic bearings are located at the bottom, one on each side, and are connected to the inner reinforced concrete lining; the seismic dampers are located on the sides, one on each side, and are connected to the inner reinforced concrete lining.

[0020] The pressure steel pipe installed inside the tunnel has a universal corrugated expansion joint installed on each side of the active fracture zone.

[0021] Preferably, during the installation of the water supply pressure steel pipe, a butt welding device is used to connect the two sections of pressure steel pipe before welding.

[0022] The docking device includes a connecting shaft, a sleeve rotatably connected to the outer side of the connecting shaft, a directional turntable fixedly connected to one end of the sleeve, a threaded portion on the outer wall of the sleeve, a threaded block threadedly connected to the outer side of the threaded portion, a fixed plate fixedly connected to one end of the connecting shaft, and one end of the sleeve rotatably connected to one side of the fixed plate. First folding rods are fixedly connected to the outer walls of both the fixed plate and the threaded block. The middle portions of the two first folding rods are rotatably connected by a pivot pin. The ends of the two first folding rods away from the connecting shaft are rotatably connected to the outer wall of a U-shaped support box. Support cylinders are rotatably connected to both ends of the U-shaped support box. The outer walls of the support cylinders are connected by a track. A first sprocket is fixedly connected to one end of each of the two support cylinders. A second sprocket is connected to the outer side of the first sprocket via a chain. The middle portion of the second sprocket is fixedly connected to the output end of a hydraulic motor. The outer wall of the hydraulic motor is fixedly connected to the inner wall of the U-shaped support box.

[0023] Preferably, a threaded rod is fixedly connected to one side of the fixed disk, a threaded ring is threadedly connected to the outer side of the threaded rod, a toothed ring is fixedly connected to the outer side of the threaded ring, a mounting ring is rotatably connected to one side of the threaded ring, a motor is fixedly connected to the outer wall of the mounting ring, a gear is fixedly connected to the output end of the motor, and the outer side of the gear is meshed with the outer side of the toothed ring.

[0024] Preferably, a sliding rod is fixedly connected to one side of the middle portion of the mounting ring, a fixed ring is fixedly connected to one end of the sliding rod, a telescopic ring is slidably connected to the outer side of the sliding rod, a hydraulic rod is fixedly connected to one side edge of the fixed ring, the output end of the hydraulic rod is fixedly connected to one side of the telescopic ring, and a second folding rod is rotatably connected to the outer wall of both the telescopic ring and the outer wall of the fixed ring. The middle portions of the two second folding rods are rotatably connected by a pivot pin, and the end of the second folding rod away from the threaded rod is rotatably connected to one side of the support plate.

[0025] Preferably, at least three support plates are provided, and the support plates are evenly distributed at equal intervals with the axis of the threaded rod as the center, and the distance from the support plates to the axis of the threaded rod is the same; at least three U-shaped support boxes are provided, and the U-shaped support boxes are evenly distributed circumferentially about the axis of the connecting shaft.

[0026] The present invention has the following beneficial effects:

[0027] 1. In this invention, by expanding the tunnel and grouting the surrounding rock, the tunnel's resistance to slippage can be improved, avoiding disasters such as damage to the surrounding rock or water inrush and mudslides in the fracture zone caused by rapid slippage of a large amount of material.

[0028] 2. In this invention, by shortening the lining sections, increasing the width of the structural joints, setting double-layer lining and isolation energy dissipation layer, the dynamic action and energy during the vibration of the active fracture are dissipated in multiple ways, reducing the energy transmitted to the water pressure steel pipe.

[0029] 3. In this invention, the use of seismic bearings, seismic dampers, and universal corrugated pipe expansion joints can not only dissipate energy significantly but also adapt to large three-dimensional deformation, thereby significantly improving the anti-slip capability of the water conveyance pressure steel pipe and ensuring that the water conveyance function is not affected.

[0030] 4. In this invention, the composite structure in the circumferential and longitudinal directions, including the double-layer lining with an isolation energy dissipation layer, post-lining consolidation grouting, and water conveying pressure steel pipe seismic and anti-fault mechanism, can significantly improve the overall structural toughness and anti-fault capability.

[0031] 5. In this invention, when supporting the pressure pipeline, it can play an automatic centering role, so that the axis of the connecting shaft is aligned with the axis of the pressure pipeline. The hydraulic motor can drive the second sprocket to rotate, so that the track can move, and the docking device can move inside the pressure pipeline, making it easy to remove the docking device after the two pressure pipelines are docked.

[0032] 6. In this invention, the motor can drive the gear to rotate, which in turn drives the gear ring to rotate, causing the threaded ring inside the gear ring to rotate. This allows the threaded ring to reciprocate on the outside of the threaded rod, connecting the mounting ring to the threaded ring. This, in turn, drives the mounting ring to reciprocate simultaneously, enabling fine-tuning of the pressure pipeline connection and adjustment of the support plate position.

[0033] 7. In this invention, the tracks inside the U-shaped support box are attached to the inner wall of the pressure pipe for support. When supporting the pressure pipe, the three U-shaped support boxes can play an automatic centering role, so that the axis of the connecting shaft is aligned with the axis of the pressure pipe, which is conducive to achieving faster docking.

[0034] 8. In this invention, the axes of two pressure steel pipes can be aligned on the same straight line. By calibrating and aligning the two pressure steel pipes, the other pressure steel pipe can be pulled closer to the first pressure steel pipe using the movement of the track, thus quickly completing the docking of the two pressure steel pipes.

[0035] 9. In this invention, the installation position of the support plate in the pressure pipeline can be flexibly adjusted. The movement of the support plate can precisely adjust the relative position of the two pressure steel pipes, making the adjustment method more accurate, convenient, and fast. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of a planar structure of a composite toughness structure for resisting adhesion and slippage through a large active fracture tunnel according to the present invention.

[0037] Figure 2 This is a cross-sectional schematic diagram of a composite toughness structure for resisting adhesion and slippage through a large active fracture tunnel according to the present invention.

[0038] Figure 3 This is a perspective view of the docking device of the present invention;

[0039] Figure 4 This is a plan view of the docking device of the present invention;

[0040] Figure 5 This is a cross-sectional view of the telescopic ring of the present invention;

[0041] Figure 6 This is a cross-sectional view of the U-shaped support box of the present invention.

[0042] Legend:

[0043] 1. Tunnel widening section; 2. Tunnel transition section; 3. Normal tunnel section; 4. Active fault main fault zone; 5. Active fault influence zone; 6. Shotcrete and anchor initial support; 7. Outer reinforced concrete lining; 8. Intermediate plain foamed concrete interlayer; 9. Inner reinforced concrete lining; 10. Structural joint; 11. Consolidation grouting ring; 12. Pressure steel pipe; 13. Seismic bearing; 14. Universal corrugated pipe expansion joint; 15. Seismic damper; 16. Steering wheel; 17. Threaded 18. Threaded part; 19. First folding rod; 20. U-shaped support box; 21. Fixed plate; 22. Threaded rod; 23. Threaded ring; 24. Mounting ring; 25. Telescopic ring; 26. Hydraulic rod; 27. Second folding rod; 28. Support plate; 29. ​​Fixed ring; 30. Motor; 31. Toothed ring; 32. Gear; 33. Track; 34. Sliding rod; 35. Chain; 36. Support cylinder; 37. First sprocket; 38. Second sprocket; 39. Connecting shaft. Detailed Implementation

[0044] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] Reference Figures 1-2 One embodiment of the present invention is as follows: taking a flat-bottomed horseshoe-shaped tunnel cross section as an example, the width and height of the excavated cross section are about 20m. The anti-adhesion and slip composite toughness structure for traversing a large active fracture tunnel in this embodiment includes a tunnel widening section 1, which is connected to the normal tunnel section 3 through a tunnel transition section 2. The inner side of the tunnel widening section 1 is provided with shotcrete and anchor initial support 6, and the inner side of the shotcrete and anchor initial support 6 is provided with lining. The lining adopts a "short lining and wide joint" double-layer concrete lining with a foamed concrete isolation and energy dissipation layer in the middle. A consolidation grouting ring 11 is provided on the outer side of the lining. A pressure steel pipe 12 is installed inside the lining. An anti-seismic bearing 13 is provided at the bottom of the pressure steel pipe 12, and anti-seismic dampers 15 are provided on both sides of the pressure steel pipe 12.

[0046] The tunnel widening section 1 includes the active fault main fault zone 4 and the active fault influence zone 5. The active fault influence zone 5 is located on both sides of the active fault main fault zone 4. The active fault influence zones 5 on both sides are connected to the adjacent sides of the two tunnel transition sections 2 respectively.

[0047] The active fracture zone 5 is equipped with universal corrugated expansion joints 14 at both ends to connect the pressure steel pipe 12.

[0048] The initial support of the shotcrete and anchor system 6 includes a concrete layer and system anchor bolts installed inside the tunnel widening section 1.

[0049] The lining consists of short sections and wide joints, forming a hinged structure. The "short lining and wide joint" double-layer concrete lining with a foamed concrete isolation and energy dissipation layer in the middle includes an outer reinforced concrete lining 7, an intermediate plain foamed concrete interlayer 8, and an inner reinforced concrete lining 9 connected sequentially from the outside to the inside. The pressure steel pipe 12 is connected to the inner reinforced concrete lining 9.

[0050] The construction method of the above-mentioned anti-stick-slip composite toughness structure includes the following steps:

[0051] When the tunnel passes through a large active fault section, the tunnel is widened in the main fault zone 4 and the influence zone 5 of the active fault to form the tunnel widening section 1. The widening size is 3m circumferential widening on the basis of the original excavation fault. The tunnel widening section 1 is connected to the normal tunnel section 3 through the tunnel transition section 2. The total length of the tunnel transition section 2 is 30m.

[0052] After excavation, initial shotcrete and anchor support 6 is constructed. The initial shotcrete and anchor support 6 specifically includes spraying 20cm thick concrete and systematically arranging 6m long hollow grouting anchors with a row spacing of 1.5 to 3m between the anchors.

[0053] After the initial support 6 of the shotcrete and anchor is completed, the outer reinforced concrete lining 7, the intermediate plain foamed concrete interlayer 8, and the inner reinforced concrete lining 9 are constructed, with thicknesses of 0.8m, 0.6m, and 1.2m, respectively. The inner and outer linings adopt a "short lining, wide joint" hinged structure, with a structural joint 10 set every 6m, and the joint width is 5cm. The concrete of the intermediate plain foamed concrete interlayer 8 is plain concrete, made of unreinforced or unstressed concrete.

[0054] After the inner reinforced concrete lining 9 is completed, holes are drilled around the tunnel to a depth of 10m. Cement grout is injected into the holes under high pressure to reinforce the surrounding rock and form a consolidation grouting ring 11.

[0055] After the consolidation grouting is completed, a water pressure steel pipe 12 is installed inside the inner reinforced concrete lining 9. The water pressure steel pipe 12 extends 15m into the tunnel transition section 2.

[0056] Every 10m, the pressure steel pipe 12 is equipped with seismic bearings 13 and seismic dampers 15 in the circumferential direction; the seismic bearings 13 are located at the bottom, one on each side, and are connected to the inner reinforced concrete lining 9; the seismic dampers 15 are located on the sides, one on each side, and are connected to the inner reinforced concrete lining 9.

[0057] The pressure steel pipe 12 installed inside the tunnel has a universal corrugated expansion joint 14 installed longitudinally on both sides of the active fracture influence zone 5.

[0058] In the above embodiments, when installing the water supply pressure steel pipe 12, the two sections of pressure steel pipe 12 are connected by a butt welding device and then welded.

[0059] refer to Figures 3-6 The docking device includes a connecting shaft 39, with a sleeve rotatably connected to the outer side of the connecting shaft 39. A direction turntable 16 is fixedly connected to one end of the sleeve. A threaded portion 18 is provided on the outer wall of the sleeve, and a threaded block 17 is threadedly connected to the outer side of the threaded portion 18. A fixed disk 21 is fixedly connected to one end of the connecting shaft 39, and one end of the sleeve is rotatably connected to one side of the fixed disk 21. First folding rods 19 are fixedly connected to the outer walls of both the fixed disk 21 and the threaded block 17. The middle portions of the two first folding rods 19 are rotatably connected by a pivot pin. Two first folding rods 19 are rotatably connected at their ends away from the connecting shaft 39 to the outer wall of the U-shaped support box 20. Support cylinders 36 are rotatably connected at both ends of the U-shaped support box 20. The outer walls of the support cylinders 36 are connected by a track 33. A first sprocket 37 is fixedly connected to one end of each of the two support cylinders 36. A second sprocket 38 is connected to the outside of the first sprocket 37 by a chain 35. The middle part of the second sprocket 38 is fixedly connected to the output end of the hydraulic motor. The outer wall of the hydraulic motor is fixedly connected to the inner wall of the U-shaped support box 20.

[0060] Specifically, one end of the connecting shaft 39 is provided with a connecting hole for connecting external ropes or engineering machinery, etc., to facilitate connection and control of the docking device when the docking device is inserted into the pressure steel pipe 12. The directional turntable 16 is used to control the rotation of the sleeve outside the connecting shaft 39. The rotation of the sleeve can cause the threaded block 17 to reciprocate at the threaded part 18, thereby adjusting the extension and retraction of the two first folding rods 19, so that the U-shaped support box 20 can move away from or towards the connecting shaft 39, so that the track 33 inside the U-shaped support box 20 can fit against the inner wall of the pressure pipe 12 for support. The U-shaped support box 20 is at least provided with In this embodiment, three U-shaped support boxes 20 are installed. The three U-shaped support boxes 20 are evenly distributed circumferentially about the axis of the connecting shaft 39. When supporting the pressure pipe 12, they can play an automatic centering role, so that the axis of the connecting shaft 39 is aligned with the axis of the pressure pipe 12. At the same time, the hydraulic motor can drive the second sprocket 38 to rotate, which in turn drives the first sprocket 37 to rotate through the chain 35, thereby causing the support cylinder 36 to rotate and the track 33 to run, so that the docking device can move inside the pressure pipe 12, making it easy to remove the docking device after the two pressure pipe sections 12 are docked.

[0061] A threaded rod 22 is fixedly connected to one side of the fixed plate 21. A threaded ring 23 is threadedly connected to the outer side of the threaded rod 22. A toothed ring 31 is fixedly connected to the outer side of the threaded ring 23. A mounting ring 24 is rotatably connected to one side of the threaded ring 23. A motor 30 is fixedly connected to the outer wall of the mounting ring 24. A gear 32 is fixedly connected to the output end of the motor 30. The outer side of the gear 32 is meshed with the outer side of the toothed ring 31.

[0062] Specifically, the motor 30 can drive the gear 32 to rotate, which in turn drives the gear ring 31 to rotate, causing the threaded ring 23 inside the gear ring 31 to rotate. This allows the threaded ring 23 to reciprocate on the outside of the threaded rod 22, connecting the mounting ring 24 to the threaded ring 23. This, in turn, drives the mounting ring 24 to reciprocate simultaneously, enabling fine-tuning of the pressure pipeline 12 during docking and adjusting the position of the support plate 28.

[0063] A slide rod 34 is fixedly connected to one side of the middle of the mounting ring 24. A fixing ring 29 is fixedly connected to one end of the slide rod 34. A telescopic ring 25 is slidably connected to the outer side of the slide rod 34. A hydraulic rod 26 is fixedly connected to one side edge of the fixing ring 29. The output end of the hydraulic rod 26 is fixedly connected to one side of the telescopic ring 25. The outer walls of the telescopic ring 25 and the outer walls of the fixing ring 29 are both connected to a second folding rod 27. The middle of the two second folding rods 27 is rotatably connected by a pivot pin. The end of the second folding rod 27 away from the threaded rod 22 is rotatably connected to one side of the support plate 28.

[0064] Specifically, when the mounting ring 24 reciprocates, it can drive the sliding rod 34 and the fixed ring 29 to move synchronously. The hydraulic rod 26 can drive the telescopic ring 25 to reciprocate outside the sliding rod 34, which can extend and retract the second folding rod 27, thereby causing the support plate 28 to move away from or closer to the threaded rod 22. At least three support plates 28 are provided. In this embodiment, four support plates 28 are installed. The four support plates 28 are evenly distributed at equal intervals with the axis of the threaded rod 22 as the center. The distance from the four support plates 28 to the axis of the threaded rod 22 is the same, and the axis of the threaded rod 22 is collinear with the axis of the connecting shaft 39.

[0065] When connecting two pressure steel pipes 12, the connecting shaft 39 is placed at the inner opening of one pressure steel pipe 12. The tracks 33 inside the U-shaped support box 20 are used to support the inner wall of the pressure pipe 12. The three U-shaped support boxes 20 provide automatic centering, aligning the axis of the connecting shaft 39 with the axis of the pressure pipe 12. The other pressure steel pipe 12 is then hoisted using lifting equipment, with four support plates 28 extending into it. The hydraulic rod 26 moves the telescopic ring 25, allowing the four support plates 28 to... 8. Simultaneously open and fit against the inner wall of another pressure steel pipe 12 for support. Since the four support plates 28 are evenly distributed at equal intervals with the axis of the threaded rod 22 as the center, and the axis of the threaded rod 22 is collinear with the axis of the connecting shaft 39, the axis of the threaded rod 22 can be centered on the axis of the other pressure steel pipe 12, so that the axes of the two pressure steel pipes 12 are on the same straight line, calibrating and aligning the two pressure steel pipes 12; by using the movement of the track 33, the other pressure steel pipe 12 can be pulled closer to one pressure steel pipe 12, completing the docking of the two pressure steel pipes 12.

[0066] Furthermore, the motor 30 can drive the gear 32 to rotate, which in turn drives the mounting ring 24 to reciprocate. This allows the support plate 28 mounted on the outside of the mounting ring 24 to reciprocate. During the docking process, as the four support plates 28 extend into the other pressure steel pipe 12, the installation position of the support plates 28 within the pressure pipe 12 can be flexibly adjusted. Simultaneously, during the process of pulling the other pressure steel pipe 12 closer to one pressure steel pipe 12, the movement of the support plates 28 can precisely adjust the relative position of the two pressure steel pipes 12. Traditional hoisting equipment can often only make rough adjustments to the position. Compared to the method of adjusting the position using hoisting equipment, the method of adjusting the docking position of the pressure pipe 12 in this invention is more precise, convenient, and faster.

[0067] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A composite toughness structure for resisting adhesion and slippage through large active fracture tunnels, characterized in that: The tunnel includes a tunnel widening section (1), which is connected to the normal tunnel section (3) through a tunnel transition section (2). The tunnel widening section (1) is provided with shotcrete and anchor initial support (6) on the inner side. The shotcrete and anchor initial support (6) is provided with a lining on the inner side. The lining adopts a short lining and wide joint double-layer concrete lining with a foam concrete isolation and energy dissipation layer in the middle. A consolidation grouting ring (11) is provided on the outer side of the lining. A pressure steel pipe (12) is installed inside the lining. An anti-seismic bearing (13) is provided at the bottom of the pressure steel pipe (12). An anti-seismic damper (15) is provided on both sides of the pressure steel pipe (12). The tunnel widening section (1) includes the active fault main fault zone (4) and the active fault influence zone (5). The active fault main fault zone (4) is surrounded by active fault influence zones (5) on both sides. The active fault influence zones (5) on both sides are connected to the adjacent sides of the two tunnel transition sections (2). The lining is a short compartment and a wide joint, forming a hinged structure. The short lining and wide joint double-layer concrete lining with a foamed concrete isolation and energy dissipation layer in the middle includes an outer reinforced concrete lining (7), a middle plain foamed concrete interlayer (8) and an inner reinforced concrete lining (9) connected sequentially from the outside to the inside. The pressure steel pipe (12) is connected to the inner reinforced concrete lining (9). The construction method of the aforementioned anti-adhesion and slippage composite toughness structure includes the following steps: When the tunnel passes through a large active fault section, the tunnel is widened in the main fault zone (4) and the active fault influence zone (5) to form a tunnel widening section (1). The widening size is 3m circumferential widening on the basis of the original excavation. The tunnel widening section (1) is connected to the normal tunnel section (3) through the tunnel transition section (2). The total length of the tunnel transition section (2) is 30m. After excavation, initial shotcrete and anchor support (6) is carried out. The initial shotcrete and anchor support (6) specifically includes spraying 20cm thick concrete and a system of 6m long hollow grouting anchors with a spacing of 1.5~3m between the anchors. After the initial support (6) of shotcrete is completed, the outer reinforced concrete lining (7), the intermediate plain foam concrete interlayer (8) and the inner reinforced concrete lining (9) are constructed with thicknesses of 0.8m, 0.6m and 1.2m respectively. The inner and outer linings adopt a short lining wide joint hinged structure, and a structural joint (10) is set every 6m with a joint width of 5cm. After the inner reinforced concrete lining (9) is completed, holes are drilled around the tunnel, with a depth of 10m. Cement grout is injected into the holes under high pressure to reinforce the surrounding rock and form a consolidation grouting ring (11). After the consolidation grouting is completed, a water pressure steel pipe (12) is installed inside the inner reinforced concrete lining (9). The water pressure steel pipe (12) extends 15m into the tunnel transition section (2). Every 10m, the pressure steel pipe (12) is equipped with seismic bearings (13) and seismic dampers (15) in the circumferential direction; the seismic bearings (13) are set at the bottom, one on each side, and are connected to the inner reinforced concrete lining (9); the seismic dampers (15) are set on the sides, one on each side, and are connected to the inner reinforced concrete lining (9). The pressure steel pipe (12) installed inside the tunnel has a universal corrugated expansion joint (14) set on each side of the active fracture influence zone (5) in the longitudinal direction. During the installation of the water supply pressure steel pipe (12), the two sections of pressure steel pipe (12) are connected by a butt welding device and then welded. The docking device includes a connecting shaft (39), a sleeve is rotatably connected to the outer side of the connecting shaft (39), a direction turntable (16) is fixedly connected to one end of the sleeve, a threaded part (18) is provided on the outer wall of the sleeve, a threaded block (17) is threadedly connected to the outer side of the threaded part (18), a fixed disk (21) is fixedly connected to one end of the connecting shaft (39), and the other end of the sleeve is rotatably connected to one side of the fixed disk (21). First folding rods (19) are fixedly connected to the outer walls of both the fixed disk (21) and the threaded block (17). The middle parts of the two first folding rods (19) are rotatably connected by a pivot pin. Two first folding rods (19) are rotatably connected to the outer wall of the U-shaped support box (20) at the ends away from the connecting shaft (39). Support cylinders (36) are rotatably connected to both ends of the U-shaped support box (20). The outer walls of the support cylinders (36) are connected by a track (33). One end of each of the two support cylinders (36) is fixedly connected to a first sprocket (37). The outer side of the first sprocket (37) is connected to a second sprocket (38) by a chain (35). The middle part of the second sprocket (38) is fixedly connected to the output end of the hydraulic motor. The outer wall of the hydraulic motor is fixedly connected to the inner wall of the U-shaped support box (20).

2. The anti-stick-slip composite toughness structure for traversing large active fracture tunnels according to claim 1, characterized in that: The active fracture influence zone (5) is provided with universal corrugated expansion joints (14) at both ends to connect the pressure steel pipe (12).

3. The anti-stick-slip composite toughness structure for traversing large active fracture tunnels according to claim 1, characterized in that: The initial support (6) of the shotcrete and anchor includes a concrete layer and system anchors installed on the inner side of the tunnel widening section (1).

4. The anti-stick-slip composite toughness structure for traversing large active fracture tunnels according to claim 1, characterized in that: A threaded rod (22) is fixedly connected to one side of the fixed disk (21). A threaded ring (23) is threadedly connected to the outer side of the threaded rod (22). A toothed ring (31) is fixedly connected to the outer side of the threaded ring (23). A mounting ring (24) is rotatably connected to one side of the threaded ring (23). A motor (30) is fixedly connected to the outer wall of the mounting ring (24). A gear (32) is fixedly connected to the output end of the motor (30). The outer side of the gear (32) is meshed with the outer side of the toothed ring (31).

5. The anti-stick-slip composite toughness structure for traversing large active fracture tunnels according to claim 4, characterized in that: A sliding rod (34) is fixedly connected to one side of the middle part of the mounting ring (24). A fixing ring (29) is fixedly connected to one end of the sliding rod (34). A telescopic ring (25) is slidably connected to the outer side of the sliding rod (34). A hydraulic rod (26) is fixedly connected to one side edge of the fixing ring (29). The output end of the hydraulic rod (26) is fixedly connected to one side of the telescopic ring (25). A second folding rod (27) is rotatably connected to the outer wall of the telescopic ring (25) and the outer wall of the fixing ring (29). The middle parts of the two second folding rods (27) are rotatably connected by a shaft pin. The end of the second folding rod (27) away from the threaded rod (22) is rotatably connected to one side of the support plate (28).

6. The anti-stick-slip composite toughness structure for traversing large active fracture tunnels according to claim 5, characterized in that: At least three support plates (28) are provided, and the support plates (28) are evenly distributed at equal intervals with the axis of the threaded rod (22) as the center. The axis distance from the support plates (28) to the threaded rod (22) is the same. At least three U-shaped support boxes (20) are provided, and the U-shaped support boxes (20) are evenly distributed in a circle about the axis of the connecting shaft (39).

Images