Tunnel crossing active fault multi-arch fault resistant system

Abstract

The application belongs to the technical field of tunnel construction, and particularly relates to a tunnel crossing active fault multi-arch anti-fault system. In the tunnel crossing active fault multi-arch anti-fault system, the tunnel assembly is limited by the transverse constraint hinge and cannot displace transversely in the overbreak space, but can only move up and down in the vertical plane of the overbreak space. The multi-arch structure at the bottom of the tunnel assembly comprises a semicircular arch frame and a plurality of sequentially connected circular arch frames. The cooperation of the semicircular arch frame and the circular arch frame can effectively support the tunnel assembly and play a certain buffering role to absorb and dissipate the fault displacement generated when the surrounding rocks on both sides of the active fault relatively displace, so that the actual fault displacement of the tunnel assembly is significantly lower than the actual fault displacement of the surrounding rocks on both sides of the active fault, thereby greatly reducing the influence of the fault displacement of the surrounding rocks on both sides of the active fault on the tunnel assembly and improving the stability and safety of the tunnel assembly.

Description

Technical Field

[0001] This invention belongs to the field of tunnel construction technology, and specifically relates to a tunnel arch anti-fault system for crossing active faults. Background Technology

[0002] When a tunnel passes through an active fault, the fault displacement is the main factor leading to the destruction of the tunnel structure, which seriously affects the construction safety and operational stability of the tunnel (Yu Haitao, Xu Hualin, Wei Yibo. Analysis method of vulnerability to fault displacement of tunnels passing through active fault zones [J]. Chinese Journal of Geotechnical Engineering, 2024, 46(10): 2060-2068.).

[0003] To address this challenge, researchers have proposed various methods to resist fault slippage, such as brittle buffer structures, flexible connection designs, and buffer layer designs. These methods can mitigate the impact of fault slippage on tunnel structures to some extent, but they still have some limitations (Cao Jun, Cui Zhen, Zhang Xiangyu, et al. Tunnel Fault Slippage Resistance Methods and Model Tests Based on Brittle Buffer Concept [J]. Journal of Tsinghua University (Natural Science Edition), 2024, 64(07): 1116-1125.).

[0004] The limitations of the aforementioned methods for preventing fault breakage are as follows:

[0005] 1. Brittle buffer structure: By setting a brittle buffer layer between the tunnel structure and the surrounding rock, the energy is absorbed by the fracture and deformation of brittle materials under stress, thereby protecting the tunnel structure. However, this design may cause local damage to the tunnel structure when the displacement of the active fault is large, and the fracture of the brittle material may require frequent replacement, which will significantly increase its operating cost.

[0006] 2. Flexible connection design: This design allows for relative displacement between the lining segments of the tunnel structure, accommodating deformation caused by active fault slippage. However, this design may exacerbate the overall deformation of the tunnel structure, especially in the core area of ​​the active fault.

[0007] 3. Buffer layer design: By setting a buffer layer between the tunnel structure and the surrounding rock, the impact of active fault displacement on the tunnel structure can be effectively mitigated. However, existing buffer layer designs may not be able to evenly distribute the displacement (relative displacement) under complex geological conditions, leading to local stress concentration and damage to the tunnel structure.

[0008] Furthermore, existing research indicates that factors such as fault dip angle and seismic intensity have a significant impact on the fault resistance of tunnel structures. For example, the smaller the fault dip angle, the lower the vulnerability of the tunnel structure, and the vulnerability of tunnel structures in the hanging wall is significantly higher than that in the footwall. Summary of the Invention

[0009] This invention provides a tunnel arch anti-fault system for tunnels crossing active faults, in order to solve the technical problem in the prior art that brittle buffer structures may cause local damage to the tunnel structure when the displacement of the active fault is large.

[0010] This invention is achieved through the following technical solution:

[0011] A tunnel crossing an active fault anti-fault system includes a tunnel component, a connecting arch system, and a lateral restraint hinge.

[0012] The tunnel assembly traverses an active fault, and the surrounding rock around the tunnel assembly has over-excavation space; the tunnel assembly consists of multiple segments, with adjacent segments connected by an elasto-plastic material;

[0013] Lateral constraint hinges are set on the left and right sides of the segment. The segment is connected to the sidewall of the over-excavated space through the lateral constraint hinges. The rotation axis of the lateral constraint hinges is parallel to the axis of the tunnel component.

[0014] The arch system is located below the tunnel assembly. The arch system includes a semi-circular arch frame and two arch frame assemblies. The two ends of the semi-circular arch frame span the active fault, and the convex side of the semi-circular arch frame abuts against the tunnel assembly. The arch frame assembly includes multiple arc arch frames. The sliding end of the first arc arch frame is slidably mounted on the semi-circular arch frame along the extension direction of the semi-circular arch frame. The second to the i-th arc arch frames are arranged sequentially in the direction away from the semi-circular arch frame. The sliding end of the i-th arc arch frame is slidably mounted on the (i-1)-th arc arch frame along the extension direction of the (i-1)-th arc arch frame. The hinged ends of all the arc arch frames are hinged to the bottom wall of the over-excavated space, and the convex side of all the arc arch frames abuts against the tunnel assembly. The two arch frame assemblies are respectively located on both sides of the semi-circular arch frame, providing vertical support for the tunnel assembly.

[0015] To better realize the present invention, the above structure is further optimized by making the radius of the semi-circular arch frame equal to the radius of the circular arc arch frame.

[0016] To better realize the present invention, the above structure is further optimized so that the distance between the hinge ends of two adjacent circular arc arch frames is equal to the radius of the circular arc arch frame.

[0017] To better realize the present invention, further optimizations are made to the above structure, wherein the surrounding rocks on both sides of the active fault are the hanging wall and footwall surrounding rocks, respectively; when the relative displacement of the hanging wall and footwall surrounding rocks is h, the uplift of the i-th circular arch frame is:

[0018]

[0019] In the formula: r is the radius of the circular arch frame.

[0020] To better realize the present invention, further optimization is made to the above structure. The sliding end of the arc arch frame is provided with a sliding sleeve. The sliding sleeve is a tubular structure. The sliding end of the arc arch frame is slidably mounted on the semi-circular arch frame or the arc arch frame through the sliding sleeve.

[0021] To better realize the present invention, the above structure is further optimized by providing a pulley on the inner sidewall of the sliding sleeve, and the pulley rolls along the extension direction of the semi-circular arch frame or the circular arc arch frame.

[0022] To better realize the present invention, further optimizations are made to the above structure, wherein the two ends of the semicircular arch frame and the hinged ends of all the circular arch frames are located on the same straight line, and the line connecting the two ends of the semicircular arch frame and the hinged ends of all the circular arch frames is parallel to the axis of the tunnel assembly.

[0023] To better realize the present invention, further optimizations are made to the above structure, wherein the longitudinal cross-section of the over-excavation space is rectangular, and the two apex corners above the over-excavation space are rounded.

[0024] Compared with the prior art, the present invention has the following advantages:

[0025] In the tunnel crossing active fault anti-fault system provided by this invention, the tunnel component is restricted by a lateral constraint hinge and cannot move laterally within the over-excavation space. It can only move up and down in the vertical plane of the over-excavation space. The arch structure at the bottom of the tunnel component includes a semi-circular arch frame and multiple sequentially connected circular arch frames. The cooperation between the semi-circular arch frame and the circular arch frame can effectively support the tunnel component and play a certain buffering role to absorb and dissipate part of the slippage generated when the surrounding rock on both sides of the active fault is relatively displaced. This makes the actual slippage borne by the tunnel component significantly lower than the actual slippage of the surrounding rock on both sides of the active fault, thereby greatly reducing the impact of the slippage of the surrounding rock on both sides of the active fault on the tunnel component and improving the stability and safety of the tunnel component. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the structure of a tunnel crossing active fault anti-fault arch system according to the present invention.

[0028] Figure 2This is a schematic diagram of the cross-section of a tunnel crossing active fault anti-fault arch system according to the present invention.

[0029] Figure 3 This is a schematic diagram of the structure of the arch system in the tunnel crossing active fault anti-fault system of the present invention.

[0030] Figure 4 This is a diagram showing the connection structure between the circular arch frame and the semi-circular arch frame in the arch system.

[0031] Figure 5 It is a sectional view of the sliding sleeve being fitted onto the semi-circular arch frame in the arch system.

[0032] Figure 6 This is a schematic diagram of the end of the semi-circular arch frame in the arch system.

[0033] In the picture:

[0034] 1. Tunnel component; 11. Segment; 12. Elasto-plastic body;

[0035] 2. Connecting arch system; 21. Semicircular arch frame; 22. Circular arch frame; 23. Sliding sleeve; 24. Pulley;

[0036] 3. Lateral constraint hinge;

[0037] 4. Active fault; 41. Hanging wall surrounding rock; 42. Footing wall surrounding rock;

[0038] 5. Over-excavation space. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be described in detail below. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other implementation methods obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0040] In the description of this invention, it should be noted that, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0041] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0042] In the embodiments of this application, such as Figures 1 to 6 As shown, the tunnel crossing the active fault's anti-fault arch system includes a tunnel component 1, an arch system 2, and a lateral restraint hinge 3; wherein,

[0043] Tunnel component 1 traverses active fault 4. Over-excavation space 5 is provided in the surrounding rock around tunnel component 1, meaning there is a gap between the outer wall of tunnel component 1 and the surrounding rock; see also Figure 1 The tunnel component 1 includes multiple segments 11, and two adjacent segments 11 are connected by an elasto-plastic body 12 to meet the deformation requirements of the two adjacent segments 11 within a certain range.

[0044] See Figure 2 The transverse constraint hinge 3 is set on the left and right sides of the segment 11. The segment 11 is connected to the side wall of the over-excavation space 5 through the transverse constraint hinge 3. The rotation axis of the transverse constraint hinge 3 is parallel to the axis of the tunnel assembly 1 to restrict the displacement of the tunnel assembly 1 in the transverse direction, but not to restrict the displacement of the tunnel assembly 1 in the vertical direction.

[0045] See Figure 1 and Figure 2 The arch-connecting system 2 is located below the tunnel component 1. The arch-connecting system 2 includes a semi-circular arch frame 21 and two arch frame components. Both ends of the semi-circular arch frame 21 span the active fault 4, and both ends of the semi-circular arch frame 21 are hinged to the bottom wall of the over-excavated space. (See [reference]). Figure 6 The protruding side of the semi-circular arch frame 21 abuts against the tunnel assembly 1;

[0046] The arch frame assembly includes multiple arc arch frames 22. The sliding end of the first arc arch frame 22 is slidably mounted on the semi-circular arch frame 21 along its extension direction. The second to the i-th arc arch frames 22 are arranged sequentially away from the semi-circular arch frame 21. The sliding end of the i-th arc arch frame 22 is slidably mounted on the (i-1)-th arc arch frame 22 along its extension direction. The hinged ends of all the arc arch frames 22 are hinged to the bottom wall of the over-excavated space 5, and their hinged method is exactly the same as that of the hinged ends of the semi-circular arch frames 21. (Refer to...) Figure 6 Furthermore, the raised sides of all the circular arch frames 22 abut against the tunnel assembly 1;

[0047] The surrounding rocks on both sides of active fault 4 are the hanging wall 41 and the footwall 42, respectively. The arch frame assembly in the hanging wall 41 will be used as an example for illustration; see [link to relevant documentation]. Figure 1 The second to the i-th circular arc arch frame 22 are arranged sequentially from left to right. The sliding end of the second circular arc arch frame 22 is slidably mounted on the first circular arc arch frame 22 along the extension direction of the first circular arc arch frame 22. The sliding end of the third circular arc arch frame 22 is slidably mounted on the second circular arc arch frame 22 along the extension direction of the second circular arc arch frame 22, and so on, to complete the connection of multiple circular arc arch frames 22.

[0048] Two arch frame components are respectively set on both sides of the semi-circular arch frame 21. That is, the two arch frame components are respectively set in the upper surrounding rock 41 and the lower surrounding rock 42 on both sides of the active fault 4, providing vertical support for the tunnel component 1.

[0049] In this embodiment, the hanging wall rock 41 refers to the hanging wall rock block above the fault plane, and the footwall rock 42 refers to the footwall rock block below the fault plane.

[0050] The following section uses a reverse fault (where the hanging wall 41 rises and the footwall 42 falls during fault displacement) as an example to illustrate the working principle of the tunnel's anti-fault arch system for traversing an active fault:

[0051] The arch system 2 provides vertical support for the tunnel component 1, and the lateral constraint hinge 3 restricts the displacement of the tunnel component 1 in the lateral direction, but does not restrict the displacement of the tunnel component 1 in the vertical direction.

[0052] When the active fault 4 shifts, the circular arch frame 22 in the hanging wall 41 rises along with the uplift of the hanging wall 41. (See below) Figure 3 In the dotted section, the height difference between the two ends of the semicircular arch 21 at the location of the active fault 4 will change (the height of the end of the semicircular arch 21 located in the upper surrounding rock 41 is greater than the height of the end of the semicircular arch 21 located in the lower surrounding rock 42). The sliding end of the first arc arch 22 located in the lower surrounding rock 42 will move upward under the action of the semicircular arch 21, causing the arc arch 22 to rotate around its hinge end. Its convex side is always abutted against the bottom of the tunnel component 1, providing stable vertical support for the tunnel component 1 and reducing the impact of the fault 4 on the tunnel component 1. At the same time, the connecting arch system 2 absorbs and dissipates part of the faulting caused by the relative displacement of the upper surrounding rock 41 and the lower surrounding rock 42, so that the actual faulting of the tunnel component 1 is significantly lower than the actual faulting of the upper surrounding rock 41 and the lower surrounding rock 42.

[0053] During the displacement of the active fault 4, the positions of two adjacent pipe sections in the tunnel assembly 1 (in the longitudinal plane) will also change. The elasto-plastic body 12 can meet the deformation requirements of the two adjacent pipe sections within a certain range, thus avoiding damage to the tunnel assembly 1 due to the displacement of the active fault 4. This significantly reduces the impact of the relative displacement of the hanging wall rock 41 and the footwall rock 42 on the tunnel assembly 1, thereby improving the stability and safety of the tunnel assembly 1.

[0054] When active fault 4 is a normal fault, its displacement direction is opposite to that of a reverse fault. In this case, the working principle of the tunnel arch anti-fault system crossing the active fault is similar to that of the reverse fault case; only the positions of the hanging wall rock 41 and the footwall rock 42 need to be interchanged. Therefore, the working principle under the normal fault case will not be repeated.

[0055] It should be noted that the aforementioned elastomeric material 12 is TST elastomeric material (Thermoplastic Styrene-Butadiene Thermoplastic Elastomer), a thermoplastic elastomer material that combines the elasticity of rubber with the processing characteristics of plastic. At room temperature, it has the high elasticity of rubber, can undergo large deformation and return to its original shape, and has certain damping characteristics, which can absorb vibration energy. TST elastomeric material is often used in components that require vibration reduction and noise reduction, such as bridge expansion joints and building sealing nodes (the connection between two adjacent segments 11 in tunnel component 1), etc.

[0056] The aforementioned lateral constraint hinge 3 is composed of multiple chain rods arranged vertically. The two ends of the chain rods are respectively hinged to the side wall of the over-excavated space 5 and the side wall of the segment 11. Since each chain rod is non-extensible, it can effectively constrain the lateral displacement of the tunnel component 1. However, since its vertical direction is a movable system (hinged structure), it does not restrict the vertical displacement of the tunnel component 1, thus satisfying the requirement that the tunnel component 1 changes with the displacement of the active fault 4.

[0057] In some embodiments, the radius of the semicircular arch frame 21 is equal to the radius of the circular arch frame 22, see [reference]. Figure 1 and Figure 3 The solid line portion in the middle;

[0058] When the arch system 2 does not shift on the active fault 4, the height of the convex side of the semicircular arch frame 21 in the arch system 2 is equal to the height of the convex side of the circular arch frame 22, so that all segments 11 in the tunnel component 1 are at the same height.

[0059] Preferably, both ends of the semicircular arch frame 21 and the hinged ends of all the circular arch frames 22 are located on the same straight line, see [reference]. Figure 2Furthermore, the lines connecting the two ends of the semicircular arch frame 21 and the hinged ends of all the circular arch frames 22 are parallel to the axis of the tunnel assembly 1, so as to better support the tunnel assembly 1.

[0060] When the active fault 4 shifts, the hanging wall rock 41 rises, and the amount of shift between the hanging wall rock 41 and the footwall rock 42 is h.

[0061] At this time, the active fault 4 passes through the center of the semicircular arch frame 22. According to the geometric relationship, the maximum uplift of the semicircular arch frame 21 is h / 2, which is only 1 / 2 of the actual displacement.

[0062] Furthermore, the uplift of the intermediate semi-circular arch frame 21 will be transferred and distributed to the circular arch frame 22 within the footwall surrounding rock 42 on its left, thereby avoiding stress concentration near the active fault 4. According to the geometric relationship, the relative displacement between the hanging wall surrounding rock 41 and the footwall surrounding rock 42 is h, and the uplift of the i-th circular arch frame 22 is:

[0063]

[0064] In the formula: r is the radius of the circular arch frame 22.

[0065] During the displacement and deformation of the active fault 4, due to the effect of gravity, each segment 11 in the tunnel assembly 1 always maintains close contact with the circular arch frame 22 or the semi-circular arch frame 21.

[0066] To accommodate the deformation of the arch system 2, two adjacent segments 11 will undergo a certain deformation around their connection point to achieve coordinated deformation with the arch system 2.

[0067] During this process, the uplift of each segment 11 is consistent with the uplift of the corresponding circular arch frame 22 or semi-circular arch frame 21 below it; therefore, the maximum uplift of tunnel component 1 is the same as the maximum uplift of the connecting arch system 2, which is 1 / 2 of the fault displacement.

[0068] This design effectively absorbs and dissipates some of the fault displacement, making the actual displacement of tunnel component 1 significantly lower than that of the hanging wall 41 and footwall 42. This greatly reduces the impact of the active fault 4 displacement on tunnel component 1 and significantly improves the safety and stability of tunnel component 1.

[0069] In some embodiments, the distance between the hinged ends of two adjacent circular arc arch frames 22 is equal to the radius of the circular arc arch frame 22.

[0070] In some embodiments, the sliding end of the arc arch frame 22 is respectively provided with a sliding sleeve 23, see [reference]. Figure 1 , Figure 3 and Figure 4The sliding sleeve 23 is a tubular structure. The sliding end of the arc arch frame 22 is slidably mounted on the semi-circular arch frame 21 or the arc arch frame 22 through the sliding sleeve 23, so that the sliding end of the arc arch frame 22 can slide more smoothly.

[0071] Preferably, the inner wall of the sliding sleeve 23 is provided with a pulley 24, see [reference]. Figure 5 The pulley 24 rolls along the extension direction of the semi-circular arch frame 21 or the circular arch frame 22 to further improve the smoothness of the sliding end of the circular arch frame 22 during sliding.

[0072] More preferably, the curvature of the axis of the sliding sleeve 23 is equal to the curvature of the arc arch frame 22, so as to ensure that the sliding end of the arc arch frame 22 can slide along the arc arch frame 22 in front of it.

[0073] In some embodiments, the longitudinal section (section along the axis of tunnel component 1) of the over-excavation space 5 is rectangular in shape, and the two apex corners above the over-excavation space 5 are rounded to avoid stress concentration in the hanging wall 41 and the hanging wall 41, which could lead to the collapse of the over-excavation space 5 and improve the safety of the tunnel crossing the active fault arch anti-fault system.

[0074] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A tunnel arch anti-fault system for crossing active faults, characterized in that: It includes a tunnel component (1), a connecting arch system (2), and a lateral restraint hinge (3); The tunnel component (1) passes through an active fault (4), and the surrounding rock of the tunnel component (1) has an over-excavation space (5); the tunnel component (1) includes multiple segments (11), and two adjacent segments (11) are connected by an elasto-plastic body (12); Lateral constraint hinges (3) are set on the left and right sides of the segment (11). The segment (11) is connected to the side wall of the over-excavation space (5) through the lateral constraint hinges (3). The rotation axis of the lateral constraint hinges (3) is parallel to the axis of the tunnel assembly (1). The arch system (2) is located below the tunnel assembly (1). The arch system (2) includes a semi-circular arch frame (21) and two arch frame assemblies. The two ends of the semi-circular arch frame (21) span the active fault (4) and are hinged to the bottom wall of the over-excavated space (5). The convex side of the semi-circular arch frame (21) abuts against the tunnel assembly (1). The arch frame assembly includes multiple arc arch frames (22). The sliding end of the first arc arch frame (22) is slidably disposed on the semi-circular arch frame (21) along the extension direction of the semi-circular arch frame (21). The second arc arch frame (22) and the i-th arc arch frame (22) are slidably disposed on the semi-circular arch frame (21) along the extension direction of the semi-circular arch frame (21). The circular arch frames (22) are arranged in sequence in the direction away from the semi-circular arch frame (21). The sliding end of the i-th circular arch frame (22) is slidably set on the i-1 circular arch frame (22) along the extension direction of the i-1 circular arch frame (22). The hinged ends of all the circular arch frames (22) are hinged to the bottom wall of the over-excavated space (5), and the protruding side of all the circular arch frames (22) abuts against the tunnel assembly (1). The two arch frame assemblies are respectively set on both sides of the semi-circular arch frame (21) to provide vertical support for the tunnel assembly (1).

2. The tunnel crossing active fault arch anti-fault system according to claim 1, characterized in that: The radius of the semicircular arch frame (21) is equal to the radius of the circular arch frame (22).

3. The tunnel crossing active fault arch anti-fault system according to claim 2, characterized in that: The distance between the hinged ends of two adjacent circular arch frames (22) is equal to the radius of the circular arch frame (22).

4. The tunnel crossing active fault arch anti-fault system according to claim 1, characterized in that: The surrounding rocks on both sides of the active fault (4) are the hanging wall (41) and the footwall (42), respectively; when the relative displacement of the hanging wall (41) and the footwall (42) is h, the uplift of the i-th circular arch frame (22) is: In the formula: r is the radius of the circular arch frame (22).

5. The tunnel crossing active fault arch anti-fault system according to claim 1, characterized in that: The sliding end of the arc arch frame (22) is provided with a sliding sleeve (23). The sliding sleeve (23) is a tubular structure. The sliding end of the arc arch frame (22) is slidably mounted on the semi-circular arch frame (21) or the arc arch frame (22) through the sliding sleeve (23).

6. The tunnel crossing active fault anti-fault arch anti-slip system according to claim 5, characterized in that: The inner wall of the sliding sleeve (23) is provided with a pulley (24), which rolls along the extension direction of the semi-circular arch frame (21) or the circular arc arch frame (22).

7. The tunnel crossing active fault anti-fault arch system according to claim 1, characterized in that: The two ends of the semicircular arch frame (21) and the hinged ends of all the circular arch frames (22) are located on the same straight line, and the line connecting the two ends of the semicircular arch frame (21) and the hinged ends of all the circular arch frames (22) is parallel to the axis of the tunnel assembly (1).

8. The tunnel crossing active fault arch anti-fault system according to claim 1, characterized in that: The longitudinal cross-section of the over-excavation space (5) is rectangular, and the two top corners of the over-excavation space (5) are rounded.

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