NPR energy dissipation reset type wedge-shaped guide tunnel anti-fault structure

Abstract

The application relates to the technical field of tunnel fault resistance, in particular to an NPR energy consumption reset wedge-shaped guide tunnel fault resistance structure. In the fault resistance structure, the upper prefabricated section, the lower prefabricated section and the intermediate prefabricated section are mutually inserted and matched through limiting assemblies, so that the radial and ring direction displacement of the intermediate prefabricated section is constrained; meanwhile, the limiting assemblies are mutually matched through the wedge-shaped inclined surface characteristics, the fault slip shearing force borne by the intermediate prefabricated section is converted into a transverse balance force and an axial driving force; the transverse balance force is mutually offset by the tenon and the mortise; and the axial driving force can push the intermediate prefabricated section to slide along the tunnel axial direction, so that the intermediate prefabricated section extrudes the NPR pad layer arranged on one side of the limiting assembly, the NPR pad layer is transversely expanded and axially contracted under pressure, the NPR pad layer deforms to absorb the fault impact energy, and the structural load is buffered. When the fault dislocation stress is dissipated, the NPR pad layer releases the stored energy, reversely pushes the intermediate prefabricated section to return to the initial butt joint position, and the self-resetting of the fault resistance structure is completed.

Description

Technical Field

[0001] This application relates to the field of tunnel anti-fault technology, and in particular to an NPR energy-dissipating and resetting wedge-shaped guide tunnel anti-fault structure. Background Technology

[0002] During construction, tunnel construction will inevitably cross active fault fracture zones. Due to the influence of crustal tectonic movements and groundwater erosion, faults are prone to circumferential shearing, radial displacement, and axial displacement deformation. Conventional cast-in-place reinforced concrete tunnel linings have high rigidity and poor deformation capacity. Even minor fault displacements can cause lining cracking, water seepage, and structural fractures, directly leading to tunnel operation failure, surrounding rock collapse, and other engineering disasters.

[0003] The mainstream anti-faulting schemes for tunnels crossing active faults include over-excavation design and isolation performance design. Over-excavation design accommodates fault displacement by expanding the excavation cross-section in the fault zone and filling it with buffer material. However, when crossing large fault zones, the over-excavation range is large and the cost is high. Furthermore, the boundary between the over-excavated and non-over-excavated sections is prone to failure due to sudden changes in stiffness. Secondly, isolation performance design reduces the transmission of shear force by setting a sliding layer between the lining and the surrounding rock. However, it cannot eliminate the forced displacement caused by faulting, and the protective effect is limited. Once the structure deforms, permanent damage occurs, requiring shutdown for maintenance, which seriously affects the safety of project operation.

[0004] Therefore, there is a need to provide an improved technical solution that addresses the shortcomings of the existing technology. Summary of the Invention

[0005] The purpose of this application is to provide an NPR energy-dissipating and resetting wedge-shaped guide tunnel anti-fault structure to solve or alleviate the problems existing in the prior art.

[0006] To achieve the above objectives, this application provides the following technical solution: An NPR energy-dissipating and resetting wedge-shaped guide tunnel anti-fault structure, the anti-fault structure includes an intermediate precast section, an upper precast section and a lower precast section, the intermediate precast section is set within the fault fracture zone, and the upper precast section and the lower precast section are distributed within the stable surrounding rock range on both sides of the intermediate precast section; Limiting components are provided at both ends of the intermediate prefabricated section, one end of the upper prefabricated section, and one end of the lower prefabricated section; the intermediate prefabricated section and the upper prefabricated section are connected to each other through the limiting components; the intermediate prefabricated section and the lower prefabricated section are connected to each other through the limiting components. The limiting component includes alternating tenons and mortises, with wedge-shaped inclined surfaces on both sides of the tenon or mortises, and the wedge-shaped inclined surfaces are inclined inward in the tunnel axial direction; when the middle precast section is inserted into the upper or lower precast section, the tenons and mortises of two adjacent limiting components are inserted into each other, and an NPR pad is provided between any tenon and mortis of the two limiting components.

[0007] The NPR energy-dissipating and resetting wedge-shaped guide tunnel anti-fault structure described above is preferably further comprising two annular steel beams, which are respectively arranged around the limiting components on both sides of the intermediate prefabricated section.

[0008] The NPR energy-dissipating and resetting wedge-shaped guide tunnel anti-fault structure described above preferably includes two steel rings, which are respectively disposed within the inner circumference of the limiting components on both sides of the intermediate prefabricated section.

[0009] The NPR energy-dissipating and resetting wedge-shaped guide tunnel anti-fault structure described above preferably includes a central reinforcement section located between the intermediate precast section and the surrounding rock.

[0010] The NPR energy-dissipating and resetting wedge-shaped guide tunnel anti-fault structure described above is preferably further comprising a side reinforcement section, wherein side reinforcement sections are provided on the periphery and upstream of the upper precast section, and on the periphery and downstream of the lower precast section.

[0011] In the NPR energy-dissipating and resetting wedge-shaped guide tunnel anti-fault structure described above, preferably, multiple perforations are evenly arranged on the annular steel beam, and an NPR anchor rod is installed in each perforation.

[0012] In the NPR energy-dissipating and resetting wedge-shaped guide tunnel anti-fault structure described above, preferably, multiple perforations are uniformly arranged on the intermediate prefabricated section, and an NPR anchor rod is installed in each perforation.

[0013] The NPR energy-dissipating and resetting wedge-shaped guide tunnel anti-fault structure described above preferably includes a hollow anchor bolt, an anchor head, an anchor, a fixing nut, a washer, and a grout stop plug. The anchor head is fixed to the bottom of the hollow anchor rod, the anchor is fixed to the anchor head, the grout stop plug is sleeved on the periphery of the hollow anchor rod, and the grout stop plug is located near the opening of the anchor rod installation hole. A gasket and a fixing nut are sequentially arranged on the side of the grout stop plug away from the surrounding rock.

[0014] In the NPR energy-dissipating and resetting wedge-shaped guide tunnel anti-fault structure described above, preferably, the anchor includes a storage tube, a pressure rod, a spring, and a rotary cutter frame. The upper end of the pressure rod is embedded in the anchor head, and the lower end of the pressure rod is fixed to the upper end of the storage tube. The upper end of the rotary cutter frame is located inside the storage tube, and the lower end of the rotary cutter frame extends out of the storage tube. A blade is provided on the side of the lower end of the rotary cutter frame facing the storage tube. The storage tube is filled with anchoring agent and a spring is installed inside the storage tube. The upper end of the spring contacts the pressure rod, and the lower end of the spring contacts the rotary cutter holder.

[0015] In the NPR energy-dissipating and resetting wedge-shaped guide tunnel anti-fault structure described above, preferably, the anchor head is provided with multiple slots on the side facing the pressure rod, the upper end of the pressure rod is a tapered part, and the tapered part at the upper end of the pressure rod is embedded in the slot end of the anchor head.

[0016] Compared with the closest prior art, the technical solution of this application has the following beneficial effects: In this anti-fault structure, the upper, lower, and intermediate precast sections are all interconnected by limiting components, thereby constraining the radial and circumferential displacement of the intermediate precast section to prevent torsion, voiding, and damage to the lining inside the precast section. At the same time, the limiting components, through the characteristics of the wedge-shaped inclined surfaces, convert the fault sliding shear force on the intermediate precast section into a lateral balancing force and an axial driving force. The lateral balancing force is canceled out by the tenon and mortise, thus preventing torsional cracking of the lining. The axial driving force can push the intermediate precast section to slide along the tunnel axis, causing the intermediate precast section to compress the NPR cushion layer set on one side of the limiting component. The NPR cushion layer expands laterally and contracts axially under pressure, allowing the deformation of the NPR cushion layer to absorb the fault impact energy and buffer the structural load. After the fault displacement stress dissipates, the NPR cushion layer releases its stored energy, thereby pushing the intermediate precast section back to its initial docking position and completing the autonomous reset of the fault-resistant structure. In other words, this fault-resistant structure can not only adapt to various angle displacement conditions of active faults, but also achieve autonomous reset of the intermediate precast section after the fault stress dissipates, thus realizing adaptive protection against fault reciprocating displacement.

[0017] By cooperating with the circumferential steel beams and steel rings, the docking positions of each set of limiting components are completely sealed, thereby ensuring that the docking positions of the two limiting components in each set have good integrity and sealing, so as to facilitate the effectiveness of subsequent adaptive movement of the intermediate prefabricated section. Attached Figure Description

[0018] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. Wherein: Figure 1This is a schematic diagram of an anti-breakage structure provided according to some embodiments of this application; Figure 2 A cross-sectional view of an anti-fracture structure provided according to some embodiments of this application; Figure 3 This is a schematic diagram of an intermediate prefabricated segment provided according to some embodiments of this application; Figure 4 This is a schematic diagram of an NPR anchor bolt provided according to some embodiments of this application; Figure 5 This is a cross-sectional view of an anchor provided according to some embodiments of this application.

[0019] Explanation of reference numerals in the attached figures: 1. Side reinforcement section; 2. Ring steel beam; 3. Middle reinforcement section; 4. NPR anchor bolt; 5. Upper precast section; 6. Limiting component; 7. Middle precast section; 8. Steel ring; 9. Lower precast section; 10. NPR pad; 11. Connecting bar; 12. Tenon; 13. Wedge-shaped bevel; 14. Mortise and tenon; 15. Fixing nut; 16. Washer; 17. Grout stopper; 18. Hollow anchor bolt; 19. Anchor head; 20. Anchor; 21. Storage tube; 22. Spring; 23. Cutter holder; 24. Blade; 25. Pressure bar. Detailed Implementation

[0020] The present application will now be described in detail with reference to the accompanying drawings and embodiments. Various examples are provided by way of interpretation and not by way of limitation. In fact, those skilled in the art will recognize that modifications and variations can be made to the present application without departing from the scope or spirit thereof. For example, a feature represented or described as part of one embodiment may be used in another embodiment to produce yet another embodiment. Therefore, it is desirable that the present application encompass such modifications and variations that fall within the scope of the appended claims and their equivalents.

[0021] In the following description, the terms "first / second / third" are used merely to distinguish similar objects and do not represent a specific order of objects. It is understood that "first / second / third" may be interchanged in a specific order or sequence where permitted, so that the embodiments of this application described herein can be implemented in an order other than that illustrated or described herein.

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

[0023] In the description of this application, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," and "bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and do not require that this application be constructed and operated in a specific orientation, and therefore should not be construed as limiting this application. The terms "connected," "linked," and "set up" used in this application should be interpreted broadly. For example, they can refer to fixed connections or detachable connections; direct connections or indirect connections through intermediate components; wired connections, radio connections, or wireless communication signal connections. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0024] The present application will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in the embodiments of the present application can be combined with each other.

[0025] According to specific embodiments of this application, such as Figure 1-5 As shown, this application provides an NPR energy-dissipating and resetting wedge-shaped guide tunnel anti-fault structure. The anti-fault structure includes an intermediate precast section 7, an upper precast section 5, and a lower precast section 9. The intermediate precast section 7 is located within the fault fracture zone, and the upper precast section 5 and the lower precast section 9 are distributed within the stable surrounding rock on both sides of the intermediate precast section 7.

[0026] Limiting components 6 are provided at both ends of the intermediate prefabricated section 7, one end of the upper prefabricated section 5, and one end of the lower prefabricated section 9; the intermediate prefabricated section 7 and the upper prefabricated section 5 are connected to each other through the limiting components 6; the intermediate prefabricated section 7 and the lower prefabricated section 9 are connected to each other through the limiting components 6.

[0027] The limiting component 6 includes alternating tenons 12 and mortises 14. Both sides of the tenon 12 or mortises 14 are wedge-shaped inclined surfaces 13, and the wedge-shaped inclined surfaces 13 are inclined inward in the tunnel axial direction. When the intermediate precast section 7 is inserted into the upper precast section 5 or the lower precast section 9, the tenons 12 and mortises 14 of the two adjacent limiting components 6 are inserted into each other, and an NPR pad layer 10 is provided between any tenon 12 and mortises 14 of the two limiting components 6.

[0028] In this anti-fault structure, the upper precast section 5, the lower precast section 9, and the intermediate precast section 7 are all interconnected by limiting components 6, thereby constraining the radial and circumferential displacement of the intermediate precast section 7 to prevent the lining inside the precast section from twisting, delaminating, or breaking. At the same time, the limiting components 6, through the characteristics of the wedge-shaped inclined surface 13, convert the fault sliding shear force on the intermediate precast section 7 into a lateral balancing force and an axial driving force. The lateral balancing force is canceled out by the tenon 12 and the mortise 14, thereby preventing the lining from twisting and cracking. The axial driving force can push the intermediate precast section 7 to slide along the tunnel axis, causing the intermediate precast section 7 to compress the NPR cushion layer 10 set on one side of the limiting component 6. The NPR cushion layer 10 expands laterally and contracts axially under pressure, allowing the deformation of the NPR cushion layer 10 to absorb the fault impact energy and buffer the structural load. After the fault displacement stress dissipates, the NPR cushion layer 10 releases its stored energy, thereby pushing the intermediate precast section 7 back to its initial docking position and completing the autonomous reset of the fault-resistant structure. That is, the fault-resistant structure can not only adapt to various angle displacement conditions of active faults, but also achieve the autonomous reset of the intermediate precast section 7 after the fault stress dissipates, thus realizing adaptive protection against fault reciprocating displacement.

[0029] In this embodiment, the intermediate precast section 7, the upper precast section 5, and the lower precast section 9 are all annular precast components. The diameters of the intermediate precast section 7, the upper precast section 5, and the lower precast section 9 are all smaller than the excavation diameter of the tunnel, so as to reserve a certain deformation space around the precast section. After the tunnel excavation is completed, the lower precast section 9, the intermediate precast section 7, and the upper precast section 5 are installed in sequence by a full-circle needle beam trolley.

[0030] The NPR pad 10 has the same outer peripheral shape as the tenon 12 so that the NPR pad 10 fills the gap between the tenon 12 and the mortise 14. The NPR pad 10 is made of NPR material, which gives it a negative Poisson's ratio characteristic and enables it to withstand large loads without deformation or failure.

[0031] The anti-fracture structure also includes two annular steel beams 2, which are respectively arranged around the limiting components 6 on both sides of the middle prefabricated section 7. In this embodiment, an annular steel beam 2 is provided around each group of two interlocking limiting components 6, that is, the annular steel beam 2 wraps around the periphery of each group of two limiting components 6, thereby protecting the limiting components 6 from the outside.

[0032] The anti-fracture structure also includes two steel rings 8, which are respectively disposed within the inner circumference of the limiting components 6 on both sides of the intermediate prefabricated section 7. In this embodiment, a steel ring 8 is provided around the periphery of each set of two interlocking limiting components 6, that is, the steel ring 8 surrounds the inner circumference of each set of two limiting components 6, thereby protecting the limiting components 6 from the inside. Through the cooperation of the circumferential steel beam and the steel ring 8, the docking position of each set of limiting components 6 is completely sealed, thereby ensuring that the docking position of each set of two limiting components 6 has good integrity and sealing, so as to facilitate the effectiveness of the subsequent adaptive movement of the intermediate prefabricated section 7.

[0033] The anti-fault structure also includes a central reinforcement section 3, which is located between the intermediate precast section 7 and the surrounding rock. In this embodiment, a pouring hole is provided on the intermediate precast section 7, and a circumferential steel mesh is preset around the intermediate precast section 7. When the central reinforcement section 3 needs to be poured, concrete is poured into the gap between the intermediate precast section 7 and the surrounding rock through the pouring hole, thereby forming the central reinforcement section 3. The central reinforcement section 3 surrounds the intermediate precast section 7 to strengthen the connection between the intermediate precast section 7 and the surrounding rock.

[0034] The anti-fault structure also includes a side reinforcement section 1, which is provided on the periphery and upstream of the upper precast section 5, and on the periphery and downstream of the lower precast section 9. In this embodiment, an outwardly extending connecting bar 11 is provided on the upstream side of the upper precast section 5, and an outwardly extending connecting bar 11 is provided on the downstream side of the lower precast section 9. After the upper precast section 5 and the lower precast section 9 are installed, a steel mesh is tied between the connecting bar 11 of the upper precast section 5 and the upstream surrounding rock lining, and a steel mesh is tied between the connecting bar 11 of the upper precast section 5 and the downstream surrounding rock lining. Then, a template is installed between the inner circumference of the upper precast section 5 and the upstream surrounding rock lining, and a template is installed between the inner circumference of the lower precast section 9 and the downstream surrounding rock. Finally, concrete is poured into the template, thereby forming a side reinforcement section 1 on the upstream side of the upper precast section 5 and the downstream side of the lower precast section 9. The side reinforcement section 1 forms the connection between the upper precast section 5, the lower precast section 9 and the adjacent surrounding rock lining, thereby making the entire anti-fault structure more firmly and reliably fixed in the tunnel, so that the anti-fault structure can effectively play its anti-fault function.

[0035] Multiple perforations are evenly distributed on the annular steel beam 2, and an NPR anchor rod 4 is installed in each perforation. In this embodiment, the NPR anchor rod 4 is anchored in the surrounding rock, and the annular steel cable is fixed by the NPR anchor rod 4, so that the annular steel beam 2 can be stably set on the periphery of the limiting component 6; the perforations on the annular steel cable are positioned to avoid the limiting component 6, so as to avoid interference between the subsequently installed NPR anchor rod 4 and the limiting component 6.

[0036] Multiple perforations are evenly distributed on the intermediate precast section 7, and an NPR anchor bolt 4 is installed in each perforation. In this embodiment, the NPR anchor bolt 4 is anchored in the surrounding rock, and a connection is established between the intermediate precast section 7 and the surrounding rock in the circumferential direction through the NPR anchor bolt 4, so as to ensure that the intermediate precast section 7 is set more stably and reliably in the tunnel.

[0037] The NPR anchor bolt 4 includes a hollow anchor bolt 18, an anchor head 19, an anchor 20, a fixing nut 15, a washer 16, and a grout stop plug 17. The anchor head 19 is fixed to the bottom of the hollow anchor bolt 18, the anchor 20 is fixed to the anchor head 19, and the grout stop plug 17 is sleeved on the periphery of the hollow anchor bolt 18, with the grout stop plug 17 located near the opening of the anchor bolt installation hole. On the side of the grout stop plug 17 away from the surrounding rock, the washer 16 and the fixing nut 15 are sequentially arranged. In this embodiment, the hollow anchor bolt 18 and the anchor head 19 are interconnected by a threaded tube. Multiple perforations are provided on the hollow anchor bolt 18 and / or the threaded tube for grout to flow from the inside of the hollow anchor bolt 18 to the outside. The grout stop plug 17 is used to seal the gap between the anchor bolt installation hole and the hollow anchor bolt 18, and the anchor 20 is used to anchor the bottom of the hollow anchor bolt 18 to the surrounding rock. The hollow anchor bolt 18 is made of NPR material.

[0038] The anchor 20 includes a storage tube 21, a pressure rod 25, a spring 22, and a rotary cutter holder 23. The upper end of the pressure rod 25 is embedded in the anchor head 19, and the lower end of the pressure rod 25 is fixed to the upper end of the storage tube 21. The upper end of the rotary cutter holder 23 is located inside the storage tube 21, and the lower end of the rotary cutter holder 23 extends out of the storage tube 21. A blade 24 is provided on the side of the lower end of the rotary cutter holder 23 facing the storage tube 21. The storage tube 21 is filled with anchoring agent, and a spring 22 is provided inside the storage tube 21. The upper end of the spring 22 contacts the pressure rod 25, and the lower end of the spring 22 contacts the rotary cutter holder 23. In this embodiment, the storage tube 21 is made of engineering plastic so that the blade 24 can pierce the storage tube 21 and allow the anchoring agent to flow out of the storage tube 21; the anchoring agent can be resin or other liquid curing agent; the rotary cutter holder 23 has an I-shaped cross-section, with the blade 24 provided at the lower end of the I-shaped rotary cutter holder 23 and multiple perforations provided at the upper end of the I-shaped rotary cutter holder 23, so that the anchoring agent can flow freely at the upper end of the rotary cutter holder 23 and fill the entire storage tube 21 with the anchoring agent.

[0039] In this embodiment, the upper end of the rotary cutter holder 23 is movably positioned inside the storage tube 21. When the anchor 20 is pressed down by external force, the spring 22 is compressed, and the blade 24 on the rotary cutter holder 23 pierces the storage tube 21, causing the anchoring agent inside to flow out. Alternatively, an internal thread can be provided in the inner wall of the storage tube 21, and an external thread can be provided at the upper end of the rotary cutter holder 23, allowing the rotary cutter holder 23 to rotate within the storage tube 21. When the NPR anchor rod 4 is inserted into the anchor rod mounting hole, the lower end of the rotary cutter holder 23 presses against the bottom of the hole. Under friction, the rotary cutter holder 23 remains stationary. Then, the hollow anchor rod 18 is rotated, causing the hollow anchor rod 18 to drive the storage tube 21 to rotate. The rotary cutter holder 23 compresses the spring 22 until the blade 24 at the lower end of the rotary cutter holder 23 pierces the storage tube 21, causing the anchoring agent inside to flow out and solidify, thus anchoring the bottom of the anchor rod in the mounting hole.

[0040] The anchor head 19 has multiple slots on the side facing the pressure rod 25. The upper end of the pressure rod 25 is tapered, and the tapered part of the upper end of the pressure rod 25 is embedded in the slot end of the anchor head 19. In this embodiment, by setting a slot at the bottom end of the anchor head 19, the tapered part of the pressure rod 25 is embedded in the bottom end of the anchor head 19. When an external force presses down on the anchor head 19, the bottom end of the anchor head 19 will expand, further fixing the anchor head 19 and the pressure rod 25 firmly. Then, by injecting concrete mortar into the hollow anchor rod 18, the concrete mortar flows out from the perforation on the hollow anchor rod 18, thereby achieving full-length anchoring of the NPR anchor rod 4 and ensuring the reliability of the NPR anchor rod 4 anchoring in the surrounding rock.

[0041] The specific construction method for this anti-faulting structure is as follows: First, after the tunnel excavation is completed, anchor holes are drilled in the surrounding rock at the installation positions of the ring steel beam 2 and the intermediate precast section 7. Then, a layer of waterproof cloth is laid on the inner wall of the tunnel. The intermediate precast section 7, which is prefabricated in the factory, is sent into the corresponding installation position in the tunnel through a full-circle needle beam trolley. The center height of the intermediate precast section 7 is adjusted, and the NPR anchor rod 4 is inserted into the anchor hole after passing through the intermediate precast section 7 and fixed. A steel mesh for fixing the central reinforcement section 3 can be pre-fitted around the intermediate precast section 7 to facilitate the subsequent grouting to form the central reinforcement section 3.

[0042] Next, two annular steel beams 2 are fixed to both sides of the intermediate precast section 7 using NPR anchor rods 4. The annular steel beams 2 can be multi-segment assembly structures to facilitate the installation and fixing of the annular steel beams 2. The fixing positions of the NPR anchor rods 4 will be smoothed with concrete mortar. Then, the precast upper precast section 5 and lower precast section 9 are sent into the tunnel from both sides of the tunnel using a full-circle needle beam trolley, and are respectively connected to the intermediate precast section 7, so that the connection point is within the coverage area of ​​the annular steel beams 2, and the tenons 12 and mortises 14 of the two mating limiting components 6 are accurately matched. At the same time, the NPR pad 10 is placed between the mating surfaces of the tenons 12 and mortises 14. Then, the steel ring 8 is fixed inside the limiting component 6, so that the limiting component 6 is completely enclosed between the steel ring 8 and the annular steel beam 2.

[0043] Subsequently, a steel mesh was tied between the connecting bar 11 of the upper precast section 5 and the upstream lining, and a steel mesh was tied between the connecting bar 11 of the lower precast section 9 and the downstream lining. Then, a formwork was installed between the inner wall of the upper precast section 5 and the upstream surrounding rock lining, and a formwork was installed between the inner wall of the lower precast section 9 and the downstream surrounding rock. Finally, concrete was poured into the formwork, thus forming a side reinforcement section 1 upstream of the upper precast section 5 and downstream of the lower precast section 9. Concrete was poured into the gap between the middle precast section 7 and the surrounding rock through the pouring hole on the middle precast section 7, thus forming a central reinforcement section 3. At this point, the construction of the tunnel anti-fault structure was completed.

[0044] When the active fault undergoes circumferential shear displacement, the shear force acts on the intermediate precast section 7, which transmits the shear force to the wedge-shaped inclined surface 13. The wedge-shaped inclined surface 13 decomposes the force into a lateral balancing force and an axial driving force. The lateral balancing force is offset by the tenon 12 and the mortise 14, thus preventing the lining from twisting and cracking. At the same time, the axial driving force pushes the intermediate precast section 7 to slide along the tunnel axis, compressing the NPR cushion layer 10. The NPR cushion layer 10 expands laterally and contracts axially under pressure, and the deformation absorbs the fault impact energy and buffers the structural load. After the fault stress dissipates, the NPR cushion layer 10 rebounds and releases energy autonomously, pushing the intermediate precast section 7 back to the initial docking position and completing autonomous repositioning.

[0045] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A NPR energy dissipation reset type wedge-shaped guide tunnel anti-fault structure, characterized in that, The anti-fault structure includes an intermediate precast section, an upper precast section, and a lower precast section. The intermediate precast section is located within the fault fracture zone, and the upper and lower precast sections are distributed within the stable surrounding rock on both sides of the intermediate precast section. Limiting components are provided at both ends of the intermediate prefabricated section, one end of the upper prefabricated section, and one end of the lower prefabricated section; the intermediate prefabricated section and the upper prefabricated section are connected to each other through the limiting components; the intermediate prefabricated section and the lower prefabricated section are connected to each other through the limiting components. The limiting component includes alternating tenons and mortises, with wedge-shaped inclined surfaces on both sides of the tenon or mortises, and the wedge-shaped inclined surfaces are inclined inward in the tunnel axial direction; when the middle precast section is inserted into the upper or lower precast section, the tenons and mortises of two adjacent limiting components are inserted into each other, and an NPR pad is provided between any tenon and mortis of the two limiting components.

2. The NPR energy dissipation reset type wedge-shaped guide tunnel anti- fault structure according to claim 1, characterized in that, The anti-fracture structure also includes two annular steel beams, which are respectively set around the limiting components on both sides of the middle prefabricated section.

3. The NPR energy-dissipating reset wedge-guided tunnel fault-tolerant structure according to claim 2, characterized in that, The anti-fracture structure also includes two steel rings, which are respectively set inside the limiting components on both sides of the middle prefabricated section.

4. The NPR energy-dissipating reset wedge-guided tunnel fault-tolerant structure according to claim 3, characterized in that, The anti-fault structure also includes a central reinforcement section, which is located between the intermediate precast section and the surrounding rock.

5. The NPR energy-dissipating reset wedge-guided tunnel fault-tolerant structure according to claim 4, characterized in that, The anti-fault structure also includes side reinforcement sections, which are provided on the periphery and upstream of the upper precast section, and on the periphery and downstream of the lower precast section.

6. The NPR energy-dissipating, reset, wedge-guided, tunnel, fault-tolerant structure of claim 2, wherein, The annular steel beam has multiple perforations evenly distributed, and an NPR anchor rod is installed in each perforation.

7. The NPR energy-dissipating and resetting wedge-shaped guide tunnel anti-fault structure according to claim 6, characterized in that, The intermediate prefabricated section has multiple perforations evenly distributed, and an NPR anchor bolt is installed in each perforation.

8. The NPR energy-dissipating and resetting wedge-shaped guide tunnel anti-fault structure according to claim 7, characterized in that, The NPR anchor bolt includes a hollow anchor bolt, an anchor head, an anchor device, a fixing nut, a washer, and a grout stop plug; The anchor head is fixed to the bottom of the hollow anchor rod, the anchor is fixed to the anchor head, the grout stop plug is sleeved on the periphery of the hollow anchor rod, and the grout stop plug is located near the opening of the anchor rod installation hole. A gasket and a fixing nut are sequentially arranged on the side of the grout stop plug away from the surrounding rock.

9. The NPR energy-dissipating and resetting wedge-shaped guide tunnel anti-fault structure according to claim 8, characterized in that, The anchor includes a storage tube, a pressure rod, a spring, and a rotary cutter holder. The upper end of the pressure rod is embedded in the anchor head, and the lower end of the pressure rod is fixed to the upper end of the storage tube. The upper end of the rotary cutter holder is located inside the storage tube, and the lower end of the rotary cutter holder extends out of the storage tube. A blade is provided on the side of the lower end of the rotary cutter holder facing the storage tube. The storage tube is filled with anchoring agent and a spring is installed inside the storage tube. The upper end of the spring contacts the pressure rod, and the lower end of the spring contacts the rotary cutter holder.

10. The NPR energy-dissipating and resetting wedge-shaped guide tunnel anti-fault structure according to claim 9, characterized in that, The anchor head has multiple slots on the side facing the pressure bar. The upper end of the pressure bar is tapered and is embedded in the slot end of the anchor head.

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