A self-adapting anti-faulting tunnel type based on variable stiffness induction and a construction method thereof

Abstract

The present application relates to a kind of based on variable stiffness induced adaptive anti-fault tunnel type and construction method, type includes strong influence section adaptive anti-fault structure type and general influence section damping structure type;Strong influence section adaptive anti-fault structure type includes: initial support, rubber damping layer, segmental assembly type concrete lining and displacement linkage component, segmental assembly type concrete lining includes multiple segmental assembly concrete lining pipe sections, multiple segmental assembly concrete lining pipe sections are equipped with displacement linkage component;General influence section damping structure type includes: initial support, rubber damping layer, general influence section lining.Compared with prior art, the present application proposes a new structure type based on variable stiffness induced concept, by joint stiffness difference induces tunnel structure displacement to tunnel pipe section, make the overall coordinated deformation of tunnel, effectively reduce the stress caused by fault dislocation structure, protect the safety and operation safety of crossing fault tunnel structure.

Description

Technical Field

[0001] This invention relates to the field of tunnel engineering technology, and in particular to an adaptive anti-slip tunnel type and construction method based on variable stiffness inducement. Background Technology

[0002] Recent historical earthquake damage data shows that tunnel structures traversing fault fracture zones suffer severe damage, including lining collapse, misalignment, and cracking. This not only causes immediate traffic disruptions and difficulties in emergency repairs, but also incurs enormous post-earthquake losses and repair costs, seriously impacting the safety of people's lives and property. Therefore, it is necessary to adopt reasonable seismic fortification measures to ensure the safety of tunnel structures traversing fault fracture zones.

[0003] Currently, there are four main seismic fortification measures for tunnel structures crossing fault fracture zones: (1) widening the excavation around the tunnel to reserve space for deformation; (2) changing the performance of the tunnel structure, reducing its mass, increasing its strength and damping, and adopting flexible structures; (3) changing the properties of the surrounding rock and reinforcing the surrounding rock mass with grouting or anchor bolts; and (4) setting up damping measures, such as damping layers, damping joints, and construction joints. Although these measures can reduce the damage to fault tunnel structures in earthquakes to a certain extent, they have not formed reasonable and effective treatment measures for large-scale dislocations caused by fault slippage, nor can they meet the requirements for adaptive fault resistance. After large-scale dislocations occur in the fault, they will still cause significant damage to the tunnel, seriously threatening the structural and operational safety of fault tunnels.

[0004] Therefore, for tunnel structures crossing faults under the coupled effects of strong earthquakes and fault slippage, it is urgent to develop a new adaptive fault-resistant technology and structural form to support the tunnel structure to adapt to large deformations caused by fault slippage, and to ensure the structural and operational safety of tunnels crossing faults. Summary of the Invention

[0005] The purpose of this invention is to overcome the defects of the existing technology and provide an adaptive anti-fault tunnel type and construction method based on variable stiffness induction. It proposes a new structural type based on the concept of variable stiffness induction, which induces the displacement of the tunnel structure to the tunnel pipe sections through the difference in joint stiffness, so as to make the overall tunnel deform in a coordinated manner, effectively reduce the structural stress caused by fault faulting, and protect the structural safety and operational safety of tunnels crossing faults.

[0006] The objective of this invention can be achieved through the following technical solutions: To determine whether a tunnel traverses an active fault posing engineering hazards, a probabilistic analysis method based on the influence of fault dislocation and strong earthquakes near the fault zone is used. The tunnel is divided into severely affected and moderately affected sections. The severely affected section refers to the area of ​​the active fault zone that is severely affected by earthquakes from the fault plane outwards. This section is subjected to the combined effects of strong ground motion and fault displacement, exhibiting large deformations along the tunnel's transverse direction. Based on previous earthquake damage surveys, phenomena such as lining collapse and fault misalignment are prone to occur.

[0007] The general impact section refers to the section that extends from the edge of the strong impact section to both sides where the impact of earthquake damage gradually decreases. This section is mainly affected by strong ground motion, is close to the epicenter, and has a more complex seismic wave frequency, making it prone to earthquake damage phenomena such as lining cracking and local detachment.

[0008] Based on the characteristics of strong ground motions near faults and the earthquake damage phenomena in the strongly affected and generally affected sections, targeted defense measures need to be taken.

[0009] This invention provides an adaptive anti-fault tunnel type based on variable stiffness-induced structure, including an adaptive anti-fault structure for strongly affected sections and a damping structure for general affected sections that are interconnected. The adaptive fault-resistant structural type of the strongly affected section includes: initial support, rubber damping layer, segmental assembled concrete lining and displacement traction component. The initial support is set in the outer layer, the rubber damping layer is set in the middle layer, the segmental assembled concrete lining and displacement traction component is set in the inner layer, and a waterproof layer is also provided between the rubber damping layer and the displacement traction component. The segmental assembled concrete lining includes multiple segmental assembled concrete lining pipe sections, and displacement entanglement components are provided between the multiple segmental assembled concrete lining pipe sections. The displacement entanglement components include rubber buffer pads and reserved sliding surfaces. The damping structure types for the general impact section include: initial support, rubber damping layer, and general impact section lining; the initial support is located on the outer layer, the rubber damping layer is located on the middle layer, and the general impact section lining is located on the inner layer.

[0010] Initial support is used to control the release of stress and deformation of the surrounding rock. The rubber damping layer uses its soft properties to widen the displacement surface of the structure, so that the inner structure has a larger displacement space and covers multiple pipe sections to form a whole.

[0011] The elastic modulus of the rubber buffer pad is adjusted according to the principle of variable stiffness. The deformation is large near the active fracture, so a smaller elastic modulus is selected; the deformation is small far from the active fracture, so a larger elastic modulus is selected. This ensures that the overall deformation of the tunnel is coordinated. When the tunnel is subjected to fault slip, the displacement of the pipe sections will be induced between the pipe sections. The deformation of the rubber buffer pad will bear the displacement and transmit it to the next pipe section. The reserved sliding surface is an auxiliary measure for the directional sliding of the pipe sections.

[0012] Furthermore, the initial support includes shotcrete, steel reinforcement, and rock-strengthening anchors.

[0013] Furthermore, the rubber damping layer is suitable for tunnel arch walls in areas with seismic intensity below 9 degrees, and is used to absorb energy generated during fault displacement and earthquakes.

[0014] Furthermore, the segmental assembled concrete lining pipe section includes the non-joint part of the lining section with strong influence, the shear key inner cylinder of the lining section with strong influence, and the shear key outer cylinder of the lining section with strong influence. The first segment of the assembled concrete lining pipe section has a shear key on the inner cylinder of the lining joint. The shear key extends out of the outer cylinder of the shear key in the lining joint of the first segment of the assembled concrete lining pipe section. The shear key can be embedded into the tail groove of the second segment of the assembled concrete lining pipe section to form a complete tunnel. A rubber buffer pad is set between the shear key and the groove. Multiple segments of the assembled concrete lining pipe section are connected by a reserved sliding surface.

[0015] The shear key and groove design allows displacement to be transferred between different assembled concrete lining sections, thereby dispersing concentrated displacement. The rubber buffer pad effectively avoids damage caused by stress concentration while allowing displacement space. The reserved sliding surface allows the sections to slide in parallel directions. The longitudinal stiffness variation and the ability to utilize the tunnel interlocking effect generated by the tunnel section group ensure that the fault displacement concentrated on the fault slip surface is evenly distributed on the strongly affected section.

[0016] Furthermore, the segmental assembled concrete lining is a reinforced concrete structure.

[0017] Furthermore, the lining of the generally affected section is a reinforced concrete structure.

[0018] Furthermore, the non-joint parts of the section lining, including shotcrete and reinforcing steel, are strongly affected.

[0019] Furthermore, the shear key internal cylinder of the section lining joint, including shotcrete and reinforcing steel, is strongly affected.

[0020] Furthermore, the shear key of the inner lining joint section and the outer cylinder, including shotcrete and reinforcing steel, strongly affect the outer cylinder.

[0021] This invention adopts different seismic isolation and damping structural types for tunnel response characteristics in sections strongly affected by active fault zones and sections generally affected by faults. These structures can effectively resist the coupling effect of strong ground motion and fault slippage, ensuring the safe operation and maintenance of tunnel structures.

[0022] This invention also provides a construction method for an adaptive anti-slip tunnel type based on variable stiffness inducement, comprising the following steps: S1. Determine whether the tunnel crosses an active fault with engineering hazards. Based on the probabilistic analysis method of the influence of fault dislocation in the active fault zone and the strong earthquake effect near the fault, the tunnel is divided into a strongly affected section and a generally affected section. S2. Adopting an adaptive fault-resistant structure for the strongly affected section, including the following steps: S21. Determine the cross-sectional shape according to the engineering requirements, calculate the internal force of the initial support concrete lining using the load-structure method, verify whether the internal force meets the relevant design specifications, and follow the construction sequence. The initial support of the entire tunnel is constructed using the mining method, and the initial support construction begins. S22. Based on engineering specifications and the analytical theory of tunnel damping layer, the design parameters of rubber damping layer are initially determined. A two-dimensional numerical model of tunnel considering strong ground motion near fault is established to solve the internal forces of segmental assembled concrete lining pipe sections. The internal forces are checked to see if they meet the relevant design specifications. After the calculation meets the design specifications, the design parameters of rubber damping layer are determined. Construction of rubber damping layer begins on the initial support. S23. By designing a variable stiffness model for the rubber buffer pad, the deformation of tunnel sections under different elastic moduli is investigated, the optimal deformation for relatively uniform deformation of each section is obtained, and the gradient of the change in elastic modulus of the rubber buffer pad is determined.

[0023] S24. Based on engineering specifications and the concept of sectional and segmented fortification, the length of the segmented assembled concrete lining pipe section is initially determined. A three-dimensional numerical model is established to solve the internal forces of the segmented assembled concrete lining pipe section. The internal forces are checked to see if they meet the relevant design specifications. After the calculation confirms compliance with the design specifications, the segment length of the segmented assembled concrete lining is determined. After the pipe sections are prefabricated in the factory, they are transported to the construction site for assembly. The shear key of the first pipe section is inserted into the groove at the tail of the second section to form a tunnel. Construction of the segmented assembled concrete lining and displacement-related components begins, including the non-joint part of the lining in the strongly affected section, the inner cylinder of the shear key in the joint part of the lining in the strongly affected section, the outer cylinder of the shear key in the joint part of the lining in the strongly affected section, rubber buffer pads, reserved sliding surfaces, and waterproof layers. S3. In the generally affected section, adopt the damping structure type of the generally affected section, including the following steps: S31. Based on the tunnel clearance size requirements of the engineering specifications, determine the initial support outline size, preliminarily determine the tunnel lining structure parameters, use the response-displacement method to calculate and analyze the internal forces of the tunnel lining structure under strong earthquakes, calculate the safety factor, and determine the lining structure parameters of the general affected section.

[0024] S32. Based on engineering specifications and the analytical theory of tunnel damping layers, the design parameters of the rubber damping layer are initially determined. A two-dimensional numerical model of the tunnel considering strong ground motion near the fault is established to solve the internal forces of the segmented concrete lining pipe sections. The internal forces are checked to see if they meet the relevant design specifications. The design parameters of the rubber damping layer are calculated after meeting the design specifications.

[0025] S33. The entire general impact section is constructed using the mining method, with initial support constructed first, followed by the lining of the general impact section.

[0026] The principle of this invention: The technical solutions include an adaptive fault-resistant structure for the strongly affected section and a seismic isolation and damping structure for the generally affected section.

[0027] For the lining of the severely affected sections, segmental lining is adopted. The adaptive fault-resistant structure of the severely affected sections includes initial support, rubber damping layer, segmental assembled concrete lining, and displacement-coupling components. The initial support is used to reinforce the surrounding rock, control its deformation, and ensure its stability. The rubber damping layer is suitable for tunnel arch walls in seismic intensity zones and can absorb energy during strong earthquakes, preventing damage to the lining structure. The segmental assembled concrete lining and displacement-coupling components are important components of the overall adaptive fault-resistant structure. The joint of each segment lining is divided into an inner cylinder and an outer cylinder, and a rubber buffer pad is installed between the inner and outer cylinders. The elastic modulus of the rubber buffer pad is adjusted according to the principle of variable stiffness, approximating the deformation of the active fracture. For larger areas, a smaller elastic modulus is chosen; for areas farther from the active fracture, the deformation is smaller, so a larger elastic modulus is chosen. When the fracture zone shifts, the lining segments closest to the core of the shift shift first shift. Then, through the action of the rubber buffer pads between segments, some of the deformation energy is absorbed, and the displacement is transferred to the next segment farther from the core of the shift shift. This process forms a chain effect in the tunnel, generating entanglement displacement between tunnel segments. Through the entanglement effect of displacement between each segment, the deformation of the fracture zone is evenly transferred to each segment, preventing the tunnel structure near the core of the shift shift from being damaged due to excessive deformation.

[0028] For the adaptive seismic isolation and damping structure of the general impact section, the structure includes initial support, rubber damping layer, and general impact section lining. The initial support is used to reinforce the surrounding rock, control its deformation, and ensure its stability. The rubber damping layer is suitable for tunnel arch walls in seismic intensity zones below level nine; it can absorb energy during strong earthquakes and prevent damage to the lining structure under strong earthquake action. The general impact section lining is used to reinforce the tunnel and prevent seepage and leakage.

[0029] Compared with the prior art, the present invention has the following advantages: This invention addresses the problem that traditional seismic design for tunnels crossing faults cannot effectively cope with large-scale dislocations in active fractures under strong earthquake-dislocation coupling. To solve this problem, a novel structural design based on the concept of variable stiffness induction is proposed. By inducing displacement of the tunnel structure between tunnel segments through the stiffness difference of the joints, the overall tunnel undergoes coordinated deformation, effectively reducing the structural stress caused by fault displacement and protecting the structural and operational safety of tunnels crossing faults. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of an adaptive anti-slip tunnel type based on variable stiffness inducement; Figure 2 This is a schematic diagram of a segment adaptive fault-resistant structure that strongly influences the structure. Figure 3 This is a schematic diagram of a typical vibration damping structure.

[0031] Figure reference numerals: 1-Initial support; 2-Rubber damping layer; 31-Liner of the generally affected section; 32-Non-joint part of the liner of the strongly affected section; 33-Inner cylinder of the shear key at the joint part of the liner of the strongly affected section; 34-Outer cylinder of the shear key at the joint part of the liner of the strongly affected section; 4-Rubber buffer pad; 5-Waterproof layer. Detailed Implementation

[0032] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. Component models, material names, connection structures, control methods, algorithms, and other features not explicitly described in this technical solution are considered common technical features disclosed in the prior art.

[0033] Example 1 This embodiment provides an adaptive anti-slip tunnel type based on variable stiffness inducement, such as... Figure 1 As shown, it includes an adaptive fault-resistant structural type for strongly affected sections and a damping structural type for general affected sections that are interconnected; like Figure 2 As shown, the adaptive fault-resistant structure of the strongly affected section includes: initial support 1, rubber damping layer 2, segmental assembled concrete lining and displacement-coupling components. Initial support 1 is located in the outer layer, rubber damping layer 2 is located in the middle layer, segmental assembled concrete lining and displacement-coupling components are located in the inner layer, and a waterproof layer 5 is provided between rubber damping layer 2 and displacement-coupling components. The segmental assembled concrete lining includes multiple segmental assembled concrete lining pipe sections, and displacement entanglement components are provided between the multiple segmental assembled concrete lining pipe sections. The displacement entanglement components include rubber buffer pads 4 and reserved sliding surfaces. like Figure 3 As shown, the damping structure of the general impact section includes: initial support 1, rubber damping layer 2, and general impact section lining 31; the initial support 1 is located in the outer layer, the rubber damping layer 2 is located in the middle layer, and the general impact section lining 31 is located in the inner layer.

[0034] Initial support 1 is used to control the release of stress and deformation of the surrounding rock. Rubber damping layer 2 uses its soft properties to widen the displacement surface of the structure, so that the inner structure has a larger displacement space and covers multiple pipe sections to form a whole.

[0035] The elastic modulus of the rubber buffer pad 4 is adjusted according to the principle of variable stiffness. The deformation is large near the active fracture, so a smaller elastic modulus is selected; the deformation is small far from the active fracture, so a larger elastic modulus is selected, so that the overall deformation of the tunnel is coordinated. When the tunnel is subjected to fault faulting, the displacement of the pipe sections will be induced between the pipe sections, which is borne by the deformation of the rubber buffer pad and transferred to the next pipe section. The reserved sliding surface is an auxiliary measure for the directional sliding of the pipe sections.

[0036] In a specific implementation, the initial support 1 includes shotcrete, steel bars, and surrounding rock reinforcement anchors.

[0037] In a specific implementation, the rubber damping layer 2 is a rubber damping layer suitable for tunnel arch walls in areas with seismic intensity of 9 degrees or less, used to absorb energy generated during fault displacement and earthquakes.

[0038] In a specific implementation, the segmental assembled concrete lining pipe section includes a non-joint part 32 of the strongly affected section lining, an inner cylinder 33 of the shear key of the strongly affected section lining joint part, and an outer cylinder 34 of the shear key of the strongly affected section lining joint part. The first segment of the assembled concrete lining pipe section has a shear key on the inner cylinder 33 of the lining joint. The shear key is the part that extends out of the outer cylinder 34 of the shear key in the lining joint of the first segment of the assembled concrete lining pipe section. The shear key can be embedded into the tail groove of the second segment of the assembled concrete lining pipe section to form a complete tunnel. A rubber buffer pad 4 is set between the shear key and the groove. Multiple segments of the assembled concrete lining pipe sections are connected by a reserved sliding surface.

[0039] The shear key and groove design allows displacement to be transferred between different assembled concrete lining pipe sections, thereby dispersing concentrated displacement. The rubber buffer pad 4 effectively avoids damage caused by stress concentration while allowing displacement space. The reserved sliding surface allows the pipe sections to slide in parallel directions. The longitudinal stiffness variation and the ability to utilize the tunnel interlocking effect generated by the tunnel pipe section group ensure that the fault displacement concentrated on the fault displacement surface is evenly distributed on the strongly affected section.

[0040] In a specific implementation, the segmental assembled concrete lining is a reinforced concrete structure.

[0041] In a specific implementation, the inner lining 31 of the general influence section is a reinforced concrete structure.

[0042] In a specific implementation, the non-joint portion 32 of the strongly affected section lining includes shotcrete and reinforcing steel.

[0043] In a specific implementation, the internal cylinder 33 of the shear key in the section lining joint that strongly affects the section includes shotcrete and reinforcing steel.

[0044] In a specific implementation, the outer cylinder 34 of the shear key in the section lining joint that strongly affects the section includes shotcrete and reinforcing steel.

[0045] This invention adopts different seismic isolation and damping structural types for tunnel response characteristics in sections strongly affected by active fault zones and sections generally affected by faults. These structures can effectively resist the coupling effect of strong ground motion and fault slippage, ensuring the safe operation and maintenance of tunnel structures.

[0046] This embodiment also provides a construction method for an adaptive anti-slip tunnel type based on variable stiffness inducement, including the following steps: S1. Determine whether the tunnel crosses an active fault with engineering hazards. Based on the probabilistic analysis method of the influence of fault dislocation in the active fault zone and the strong earthquake effect near the fault, the tunnel is divided into a strongly affected section and a generally affected section. S2. Adopting an adaptive fault-resistant structure for the strongly affected section, including the following steps: S21. Determine the cross-sectional shape according to the engineering requirements, calculate the internal force of the initial support concrete lining using the load-structure method, verify whether the internal force meets the relevant design specifications, and follow the construction sequence. The initial support 1 of the entire tunnel is constructed using the mining method. Start construction of initial support 1. S22. Based on engineering specifications and tunnel vibration damping layer analysis theory, the design parameters of rubber vibration damping layer 2 are initially determined. A two-dimensional numerical model of the tunnel considering strong ground motion near the fault is established to solve the internal forces of the segmental assembled concrete lining pipe section. The internal forces are checked to see if they meet the relevant design specifications. After the calculation meets the design specifications, the design parameters of rubber vibration damping layer 2 are determined. Construction of rubber vibration damping layer 2 begins on initial support 1. S23. By designing a variable stiffness model of rubber buffer pad 4, the deformation of tunnel sections under different elastic moduli is investigated, the optimal deformation amount with relatively uniform deformation of each section is obtained, and the gradient of the change of elastic modulus of rubber buffer pad 4 is determined.

[0047] S24. Based on the engineering specifications and the concept of sectional and segmented defense, the length of the segmented assembled concrete lining pipe section is initially determined. A three-dimensional numerical model is established to solve the internal forces of the segmented assembled concrete lining pipe section. The internal forces are checked to see if they meet the relevant design specifications. After the calculation meets the design specifications, the segment length of the segmented assembled concrete lining is determined. After the pipe sections are prefabricated in the factory, they are transported to the construction site for assembly. The shear key of the first pipe section is inserted into the groove at the tail of the second section to form a tunnel. Construction of the segmented assembled concrete lining and displacement-related components begins, including the non-joint part of the lining in the strongly affected section 32, the inner cylinder of the shear key in the joint part of the lining in the strongly affected section 33, the outer cylinder of the shear key in the joint part of the lining in the strongly affected section 34, the rubber buffer pad 4, the reserved sliding surface, and the waterproof layer 5. S3. In the generally affected section, adopt the damping structure type of the generally affected section, including the following steps: S31. Based on the tunnel clearance size requirements of the engineering specifications, determine the outline size of the initial support 1, preliminarily determine the tunnel lining structure parameters, use the response-displacement method to calculate and analyze the internal forces of the tunnel lining structure under strong earthquakes, calculate the safety factor, and determine the structural parameters of the lining 31 in the general influence section.

[0048] S32. Based on engineering specifications and the analytical theory of tunnel damping layers, the design parameters of rubber damping layer 2 are initially determined. A two-dimensional numerical model of the tunnel considering strong ground motion near the fault is established to solve the internal forces of the segmental concrete lining pipe sections. The internal forces are checked to see if they meet the relevant design specifications. The design parameters of the rubber damping layer are calculated after meeting the design specifications.

[0049] S33. The entire general impact section is constructed using the mining method, with initial support 1 constructed first, followed by the lining 31 of the general impact section.

[0050] The principle of this embodiment: Firstly, the technical solutions include adaptive fault-resistant structures for the strongly affected sections and seismic isolation and damping structures for the generally affected sections, such as... Figure 1 As shown.

[0051] For sections with strong impact, segmental lining is used, such as... Figure 2 As shown, the strongly affected section's adaptive fault-resistant structure includes initial support 1, rubber damping layer 2, segmental assembled concrete lining, and displacement-coupling components. Initial support 1 is used to reinforce the surrounding rock, control its deformation, and ensure its stability. Rubber damping layer 2 is suitable for tunnel arch walls in seismic intensity zones below 9 degrees, capable of absorbing energy during strong earthquakes and preventing damage to the lining structure. The segmental assembled concrete lining and displacement-coupling components are important components of the overall adaptive fault-resistant structure. Each segment of the lining is divided into an inner cylinder and an outer cylinder at its joint, with a rubber buffer pad 4 placed between them. The elastic modulus of the rubber buffer pad 4 is adjusted according to the principle of variable stiffness, approaching the active fracture. For large deformations, a smaller elastic modulus is chosen; for smaller deformations further from the active fracture, a larger elastic modulus is chosen. When the fracture zone shifts, the lining segments closest to the core of the shift first shift, then absorb some of the deformation energy through the inter-segment rubber buffer pads 4, and transfer the displacement to the next segment further away from the core of the shift. This process creates a chain effect in the tunnel, resulting in entanglement displacement between tunnel segments. Through the entanglement effect of displacement between each segment, the deformation of the fracture zone is evenly transferred to each segment, preventing the tunnel structure near the core of the shift from being damaged due to excessive deformation.

[0052] For general-affected adaptive seismic isolation structures, such as Figure 3As shown, the structure includes initial support 1, rubber damping layer 2, and general impact section lining 31. Initial support 1 is used to reinforce the surrounding rock, control its deformation, and ensure its stability. Rubber damping layer 2 is suitable for tunnel arch walls in seismic intensity zones below 9 degrees; it can absorb energy during strong earthquakes and prevent damage to the lining structure under strong earthquake action. General impact section lining 31 is used to reinforce the tunnel and prevent seepage and leakage.

[0053] Components not described in detail in this embodiment are all existing components that can be purchased through public channels.

[0054] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. An adaptive anti-slip tunnel type based on variable stiffness-induced displacement, characterized in that, This includes interconnected, highly influential, adaptive fault-resistant structural types and general-influence, damping structural types; The adaptive fault-resistant structure of the strongly affected section includes: initial support (1), rubber damping layer (2), segmental assembled concrete lining and displacement-coupling component. The initial support (1) is located on the outer layer, the rubber damping layer (2) is located on the middle layer, and the segmental assembled concrete lining and displacement-coupling component is located on the inner layer. A waterproof layer (5) is also provided between the rubber damping layer (2) and the displacement-coupling component. The segmental assembled concrete lining (3) includes multiple segmental assembled concrete lining pipe sections, and the displacement entanglement component is provided between the multiple segmental assembled concrete lining pipe sections. The displacement entanglement component includes a rubber buffer pad (4) and a reserved sliding surface. The damping structure of the general impact section includes: initial support (1), rubber damping layer (2), and general impact section lining (31); the initial support (1) is located on the outer layer, the rubber damping layer (2) is located on the middle layer, and the general impact section lining (31) is located on the inner layer. The segmental assembled concrete lining pipe section includes the non-joint part of the strongly affected section lining (32), the shear key inner cylinder of the strongly affected section lining joint part (33), and the shear key outer cylinder of the strongly affected section lining joint part (34). The shear key is provided on the inner cylinder (33) of the shear key of the strong influence section of the first segment of the assembled concrete lining pipe section. The shear key is the part that extends out of the outer cylinder (34) of the shear key of the strong influence section. The shear key can be embedded into the tail groove of the second segment of the assembled concrete lining pipe section to form a complete tunnel. A rubber buffer pad (4) is set between the shear key and the groove. Multiple segments of the assembled concrete lining pipe sections are connected by a reserved sliding surface.

2. The adaptive anti-slip tunnel type based on variable stiffness induction according to claim 1, characterized in that, The initial support (1) includes shotcrete, steel reinforcement and surrounding rock reinforcement anchors.

3. The adaptive anti-slip tunnel type based on variable stiffness induction according to claim 1, characterized in that, The rubber damping layer (2) is a rubber damping layer for tunnel arch walls in areas with seismic intensity of 9 degrees or less, used to absorb energy generated during fault displacement and earthquakes.

4. The adaptive anti-slip tunnel type based on variable stiffness induction according to claim 1, characterized in that, The segmental assembled concrete lining is a reinforced concrete structure.

5. The adaptive anti-slip tunnel type based on variable stiffness induction according to claim 1, characterized in that, The lining (31) of the general influence section is a reinforced concrete structure.

6. The adaptive anti-slip tunnel type based on variable stiffness induction according to claim 1, characterized in that, The non-joint portion (32) of the lining of the strongly affected section includes shotcrete and reinforcing steel.

7. The adaptive anti-slip tunnel type based on variable stiffness induction according to claim 1, characterized in that, The inner cylinder (33) of the shear key of the lining joint of the strongly affected section includes shotcrete and steel reinforcement.

8. The adaptive anti-slip tunnel type based on variable stiffness induction according to claim 1, characterized in that, The shear key outer cylinder (34) of the inner lining joint of the strongly affected section includes shotcrete and steel reinforcement.

9. A construction method for an adaptive anti-slip tunnel type based on variable stiffness-induced tunneling, characterized in that, Includes the following steps: S1. Determine whether the tunnel crosses an active fault with engineering hazards. Based on the probabilistic analysis method of the influence of fault dislocation in the active fault zone and the strong earthquake effect near the fault, the tunnel is divided into a strongly affected section and a generally affected section. S2. Adopting an adaptive fault-resistant structure for the strongly affected section, including the following steps: S21. Determine the cross-sectional form according to the engineering requirements, calculate the internal force of the initial support concrete lining using the load-structure method, verify whether the internal force meets the relevant design specifications, and follow the construction sequence. The initial support of the tunnel throughout the entire tunnel (1) is constructed using the mining method, and the initial support (1) is started. S22. Based on the engineering specifications and the analytical theory of tunnel damping layer, the design parameters of rubber damping layer (2) are initially determined. A two-dimensional numerical model of the tunnel considering strong ground motion near the fault is established to solve the internal forces of the segmented assembled concrete lining pipe section. The internal forces are checked to see if they meet the relevant design specifications. After the internal forces meet the design specifications, the design parameters of rubber damping layer (2) are determined. Rubber damping layer (2) is constructed on the initial support (1). S23. By designing a variable stiffness model of the rubber buffer pad (4), we explored the deformation of the tunnel pipe section under different elastic moduli, obtained the optimal deformation amount with relatively uniform deformation of each pipe section, and determined the gradient of the change of elastic modulus of the rubber buffer pad (4). S24. Based on the engineering specifications and the concept of sectional and segmented defense, the length of the segmented assembled concrete lining pipe section is initially determined. A three-dimensional numerical model is established to solve the internal forces of the segmented assembled concrete lining pipe section. The internal forces are checked to see if they meet the relevant design specifications. After the calculation meets the design specifications, the segment length of the segmented assembled concrete lining is determined. After the pipe sections are prefabricated in the factory, they are transported to the construction site for assembly. The shear key of the first pipe section is inserted into the groove at the tail of the second section to form a tunnel. Construction of the segmented assembled concrete lining and displacement-related components begins, including the non-joint part of the lining in the strongly affected section (32), the inner cylinder of the shear key in the joint part of the lining in the strongly affected section (33), the outer cylinder of the shear key in the joint part of the lining in the strongly affected section (34), the rubber buffer pad (4), the reserved sliding surface, and the waterproof layer (5). S3. In the generally affected section, adopt the damping structure type of the generally affected section, including the following steps: S31. Based on the tunnel clearance size requirements of the engineering specifications, determine the outline size of the initial support (1), preliminarily determine the tunnel lining structure parameters, use the reaction-displacement method to calculate and analyze the internal forces of the tunnel lining structure under strong earthquakes, calculate the safety factor, and determine the structural parameters of the lining (31) of the general influence section. S32. Based on the engineering specifications and the analytical theory of tunnel damping layer, the design parameters of rubber damping layer (2) are initially determined. A two-dimensional numerical model of the tunnel considering strong ground motion near the fault is established to solve the internal forces of the segmented concrete lining pipe section. The internal forces are checked to see if they meet the relevant design specifications. The design parameters of rubber damping layer (2) after meeting the design specifications are calculated. S33. The entire general impact section is constructed using the mining method, with initial support (1) constructed first, followed by the lining (31) of the general impact section.

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