Longitudinal anti-error damping device for penetrating active fault tunnel

Abstract

The invention provides a longitudinal anti-dislocation damping device for a tunnel penetrating through an active fault, and relates to the field of tunnel engineering, the longitudinal anti-dislocation damping device comprises a lining section, and a through hole is formed in the pipe wall of the lining section in the extending direction of the section; the joint waterproof piece is arranged outside the butt joint of the lining sections; the flexible joint is provided with a hole allowing the steel cable to pass through, and the flexible joint is arranged at the butt joint position of the end faces of the lining sections and located between the two lining sections; the steel cable anchorage devices are arranged at the ends of the lining sections and used for connecting and tensioning steel cables; the steel cable and the connecting steel cable anchorage device penetrate through the through hole of the lining section and the hole of the flexible connector and penetrate through the influence section of the tunnel penetrating through the movable fault, and the steel cable enables the lining section to be attached to the flexible connector under the tension of the steel cable anchorage device. According to the longitudinal anti-error damping device, the longitudinal rigidity loss of the lining can be reduced to a great extent, and the emergency rescue time can be shortened.

Description

Technical Field

[0001] The invention relates to the technical field of tunnel engineering, and in particular to a longitudinal anti-misalignment and shock-absorbing device for a tunnel passing through an active fault. Background Art

[0002] At present, many large infrastructures in western regions cannot avoid active faults. The existing anti-misalignment and shock-absorbing measures through active faults will still cause large misalignment and water leakage under large dislocation conditions. Existing studies have shown that in the process of tunnel anti-misalignment, many projects use shock-absorbing joints, flexible joints, shock-absorbing layers and other measures, but active faults produce great dislocations at the fault rupture surface, causing the tunnel to have misalignment and longitudinal discontinuity. Its waterproofing project and later emergency repair project are difficult to implement quickly. Therefore, how to enhance the anti-misalignment and shock-absorbing performance of tunnels has become a technical problem that needs to be solved. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art or related technology, and discloses a longitudinal anti-dislocation and shock-absorbing device for a tunnel passing through an active fault, which can solve the problems of large-scale tunnel damage, water leakage and rescue difficulties caused by the dislocation of the tunnel passing through the active fault.

[0004] The invention discloses a longitudinal anti-dislocation and shock-absorbing device for a tunnel passing through an active fault, comprising: a lining segment, which is arranged inside the primary lining of the tunnel, and the tube wall of the lining segment is provided with a through hole along the extension direction of the segment, so that a steel cable can pass through the through hole; a joint waterproofing member, which is arranged outside the butt joint of the lining segment, and the joint waterproofing member has elasticity along the extension direction of the tunnel; a flexible joint, which has a hole allowing the steel cable to pass through, is arranged at the end surface of the lining segment, is located between two lining segments, and is used to absorb fault dislocation and seismic wave energy (buffer the extrusion pressure between the lining segments); a steel cable anchor, which is arranged at the end of the lining segment and is used to connect and tension the steel cable; a steel cable, which is connected to the steel cable anchor and passes through the through hole of the lining segment and the hole of the flexible joint, and passes through a plurality of lining segments (penetrating the tunnel section where the active fault affects the tunnel), and the steel cable makes the lining segment fit with the flexible joint under the tension of the steel cable anchor.

[0005] In this technical solution, the longitudinal deformation of the tunnel is constrained to a hinge type. Under the combined action of dislocation and seismic motion, the seismic energy can be transferred to flexible joints with lower stiffness. With the support of the steel cable (tensioning force), the lining segments are allowed to produce a certain rotation and displacement. The good elasticity of the waterproof parts can reduce water leakage.

[0006] According to the longitudinal anti-misalignment and shock-absorbing device for penetrating active fault tunnels disclosed in the present invention, preferably, it also includes: a lubricating layer, arranged between the lining segment and the primary lining, for reducing the friction coefficient between the lining segment and the primary lining, thereby adjusting the longitudinal deformation of the lining segment.

[0007] According to the longitudinal anti-misalignment and shock-absorbing device for penetrating an active fault tunnel disclosed in the present invention, preferably, the lubricating layer is a waterproof membrane or a lubricated metal plate.

[0008] According to the longitudinal anti-misalignment and shock-absorbing device for tunnels passing through active faults disclosed in the present invention, preferably, the anchor is a prestressed tension anchor to apply prestress to the concrete lining segment.

[0009] According to the longitudinal anti-misalignment and shock-absorbing device for passing through an active fault tunnel disclosed in the present invention, preferably, the joint waterproofing member is a cold-bent thin-walled corrugated pipe, which can be in a W-shape, Ω-shape, square, U-shape, etc., and the pipe body is sleeved on the outside of the butt joint.

[0010] According to the longitudinal anti-misalignment and shock-absorbing device for penetrating active fault tunnels disclosed in the present invention, preferably, the tensile strength of the steel cable is calculated and allocated according to the friction coefficient in actual engineering and the weight of the tunnel segment, and a safety magnification factor of 1.2 is guaranteed.

[0011] According to the longitudinal anti-misalignment shock absorbing device for tunnels passing through active faults disclosed in the present invention, preferably, the flexible joint is made of natural rubber, butyl rubber or high damping rubber.

[0012] According to the longitudinal anti-dislocation and shock-absorbing device for a tunnel passing through an active fault disclosed in the present invention, preferably, when the dislocation amount of the active fault is greater than 0.5 m, the length of the lining segment is less than 6 m.

[0013] According to the longitudinal anti-dislocation and shock-absorbing device for passing through an active fault tunnel disclosed in the present invention, preferably, when the active fault dislocation is less than 0.3m, the width of the flexible joint is 0.1m, and when the active fault dislocation is greater than 0.3m, the width of the flexible joint is 0.2m.

[0014] According to the longitudinal anti-misalignment and shock-absorbing device for tunnels passing through active faults disclosed in the present invention, preferably, the distribution of bending moment values ​​of the active faults is calculated according to the inclination of the active faults and the properties of the surrounding rock, and the defense length is determined according to the distribution of bending moment values, thereby determining the number of lining segments.

[0015] The beneficial effects of the present invention include at least: under the condition of large dislocation caused by penetrating active faults in strong earthquake zones, adaptive deformation can be generated, thereby reducing irreversible damage to the overall structure and greatly reducing the loss of longitudinal stiffness of the lining; the high strength of the steel cables themselves can control the angular displacement of flexible joints and lining segments to ensure the integrity of the tunnel; the certain compressive resistance of the flexible material can also reduce the collision damage between lining segments; the waterproof parts can reduce water leakage; the lubricating layer can also reduce the friction damage of the initial lining to the lining segments and further adjust the longitudinal deformation of the lining. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The overall structural schematic diagram of a longitudinal anti-misalignment and shock-absorbing device for passing through an active fault tunnel according to an embodiment of the present invention is shown.

[0017] Figure 2 A schematic cross-sectional view of a lining segment according to an embodiment of the present invention is shown.

[0018] Figure 3 A schematic diagram of the range of values ​​of the defense length according to an embodiment of the present invention is shown.

[0019] Figure 4 A schematic diagram of the structure of a prestressed tension anchor according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0020] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0021] It should be understood that in the description of the present invention, the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. The following description sets forth many specific details to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and therefore, the present invention is not limited to the limitations of the specific embodiments disclosed below.

[0022] In view of the fact that existing anti-dislocation and shock-absorbing measures for tunnels through active faults still produce large misalignment and water leakage under large dislocation conditions, an embodiment of the present invention provides a longitudinal anti-dislocation and shock-absorbing device for tunnels through active faults, such as Figure 1 and Figure 2As shown, the longitudinal anti-misalignment and shock-absorbing device includes: a lining segment 6, which is arranged inside the primary lining 5 of the tunnel, and the tube wall of the lining segment is provided with a through hole along the extension direction of the segment so that the steel cable can pass through the through hole; a corrugated tube 2, which is arranged outside the butt joint of the lining segment; a flexible joint 4, which has a hole allowing the steel cable to pass through, is arranged at the end surface of the lining segment, is located between two lining segments, and is used to buffer the extrusion force between the lining segments; a prestressed tensioning anchor 1, which is arranged at the end of the lining segment and is used to connect and tension the steel cable; a steel cable 3, which is connected to the steel cable anchor and passes through the through hole of the lining segment and the hole of the flexible joint, passes through multiple lining segments, and penetrates the affected section of the tunnel through the active fault. The steel cable makes the lining segment fit with the flexible joint under the tension of the steel cable anchor. The easy-sliding material 7 is arranged between the lining segment and the primary lining to improve the sliding property of the lining segment when it is dislocated. A waterproof membrane can be used, or steel plates can be arranged at intervals and coated with lubricating oil.

[0023] According to the above embodiment, preferably, the bellows can be in a W-shape, an Ω-shape, a square shape, a U-shape, etc., and its thickness can be adjusted according to the flexibility ratio F. A =F B Sure,

[0024]

[0025] Where E represents the elastic modulus, the subscripts rock and tunnel of E represent the surrounding rock and tunnel, joint represents the bellows joint, v represents the Poisson's ratio, R is the tunnel radius, and I is the moment of inertia of the tunnel per unit length.

[0026] According to the above embodiment, preferably, the tensile strength of the steel cable can be calculated and allocated according to the friction coefficient in the actual project and the weight of the tunnel segment (lining segment), and a safety magnification factor of 1.2 can be ensured. The steel cable can be 6*25FI type steel wire rope, 6*37 type steel wire rope, etc.

[0027] According to the above embodiment, preferably, the lining segment length is selected: the commonly used existing segments are 6m, 9m, and 12m. When the active fault dislocation is greater than 0.5m, it is recommended to perform nonlinear analysis in combination with finite element software to reduce the lining segment length, such as 3m, 5m, etc.

[0028] like Figure 3 As shown, according to the above embodiment, preferably, the calculation process of the defense length (the total length of the longitudinal anti-misalignment shock absorbing device disclosed in the present invention) includes: according to the large-scale finite element software ABAQUS, the fault dip angle is 80°, the surrounding rock grade is grade IV, the broken zone is grade V, and the broken zone width is 40m. The result is as follows Figure 3 As shown in the figure, the defense length is within 50m-150m, and the defense length is the width of the broken zone D + 9.2R. Different fault dips and surrounding rock properties require the defense length to be determined based on the actual site.

[0029] According to the above embodiment, preferably, the flexible joint adopts flexible connecting materials, such as natural rubber, butyl rubber, high damping rubber, etc., and the joint width can be 0.1m when the displacement value is less than 0.3m, and 0.2m when it is greater than 0.3m.

[0030] like Figure 4 As shown, according to the above embodiment, preferably, after the steel cable passes through the lining segment and the flexible joint, the steel cable is tensioned by the anchors at both ends to make the segment and the joint tightly connected, thereby strengthening the longitudinal integrity of the tunnel. The installation structure of the prestressed tension anchor includes: an anchor pad 8, an anchor plate 9, a steel cable clip 10, and an expansive concrete 11. The anchor pad is connected to the anchor plate, and a steel cable clip is arranged in the middle of the anchor plate. The strength of the expansive concrete is higher than that of the lining concrete. The steel cable 3 passes through the through hole inside the lining segment, the steel cable clip and the expansive concrete to apply prestress to the lining segment.

[0031] Another embodiment of the present invention further discloses a specific construction method of the longitudinal anti-misalignment and shock-absorbing device for passing through an active fault tunnel of the above embodiment, comprising:

[0032] Step 1: Use the finite element software ABAQUS to establish a finite element model, calculate the distribution of the bending moment value according to the fault dip angle and surrounding rock properties, and thus determine the defense length range. The selection of the defense length range is as follows: Figure 3 shown.

[0033] Step 2: During the formwork construction of the primary lining, reserve space for the corrugated pipe according to the different shapes of the corrugated pipe.

[0034] Step 3: Apply waterproof membrane directly between the primary lining and the lining segment or place steel plates at intervals (and apply lubricating oil on the steel plates) to reduce friction.

[0035] Step 4: Calculate the number of steel cables according to the length of the lining segment and evenly distribute them in the cross section of the lining segment. The distribution of the steel cables is as follows: Figure 2 shown.

[0036] Step 5: After the tunnel segment (lining segment) is accurately positioned on site, the corrugated pipe is installed and fixed.

[0037] Step six: After the flexible joints with holes and anchors are accurately positioned in sequence, the steel cable is passed through one end and out from the end of the defense length. By tensioning the steel cable, the lining segments and the flexible joints are tightly combined.

[0038] It can be seen from the above embodiments that a certain number of steel cables are passed through the lining segments to achieve a "hinge" connection in form, and the joints are filled with flexible materials, and covered with waterproof parts with good tensile properties for waterproofing. Finally, the steel cables are tensioned at both ends of the tunnel to achieve a tight connection between the segments. Under the condition of large dislocation caused by passing through active faults in strong earthquake zones, the lining structure can produce adaptive deformation. The lining joint not only controls its angular displacement through the high strength of the steel cable itself, but also its certain compressive resistance of the flexible material also reduces the damage between the linings. Taking into account the technical solution provided by the present invention, it can provide practical guidance for tunnels with large dislocations passing through active faults.

[0039] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A longitudinal anti-misalignment and shock-absorbing device for a tunnel passing through an active fault, characterized in that: include: The lining segment is arranged inside the primary lining of the tunnel, and the wall of the lining segment is provided with a through hole along the extending direction of the segment so that the steel cable can pass through the through hole; A joint waterproofing member is arranged outside the butt joint of the lining segment, and the joint waterproofing member is stretchable in the direction along which the tunnel extends; A flexible joint, having a hole for allowing the steel cable to pass through, is provided at the end face joint of the lining segment and between two lining segments, and is used to absorb fault dislocation and seismic wave energy; A steel cable anchor, provided at the end of the lining segment, for connecting and tensioning the steel cable; The steel cable is connected to the steel cable anchor and passes through the through hole of the lining segment and the hole of the flexible joint, and comes out after passing through multiple lining segments. The steel cable makes the lining segment fit with the flexible joint under the tension of the steel cable anchor.

2. The longitudinal anti-misalignment and shock-absorbing device for tunnels passing through active faults according to claim 1 is characterized in that: Also includes: A lubricating layer is provided between the lining segment and the primary lining, and is used to reduce the friction coefficient between the lining segment and the primary lining, thereby adjusting the longitudinal deformation of the lining segment.

3. The longitudinal anti-misalignment and shock-absorbing device for tunnels passing through active faults according to claim 2 is characterized in that: The lubricating layer is a waterproof film or a lubricated metal sheet.

4. The longitudinal anti-misalignment and shock-absorbing device for tunnels passing through active faults according to claim 1, characterized in that: The steel cable anchor is a prestressed tension anchor to apply prestress to the concrete lining segment.

5. The longitudinal anti-misalignment and shock-absorbing device for tunnels passing through active faults according to claim 1, characterized in that: The joint waterproof part is a cold-bent thin-wall corrugated pipe, and the pipe body is sleeved on the outside of the butt joint.

6. The longitudinal anti-misalignment and shock-absorbing device for tunnels passing through active faults according to claim 1, characterized in that: The tensile strength of the steel cable is calculated and allocated based on the friction coefficient and the weight of the tunnel segment in the actual project, and a safety magnification factor of 1.2 is guaranteed.

7. The longitudinal anti-misalignment and shock-absorbing device for tunnels passing through active faults according to claim 1, characterized in that: The flexible joint is made of natural rubber, butyl rubber or high damping rubber.

8. The longitudinal anti-misalignment and shock-absorbing device for tunnels passing through active faults according to any one of claims 1 to 7, characterized in that: When the displacement of the active fault is greater than 0.5 m, the length of the lining segment is less than 6 m.

9. The longitudinal anti-misalignment and shock-absorbing device for tunnels passing through active faults according to any one of claims 1 to 7, characterized in that: When the active fault dislocation is less than 0.3 m, the width of the flexible joint is 0.1 m. When the active fault dislocation is greater than 0.3 m, the width of the flexible joint is 0.2 m.

10. The longitudinal anti-misalignment and shock-absorbing device for tunnels passing through active faults according to any one of claims 1 to 7, characterized in that: The bending moment distribution of the active fault is calculated according to the inclination of the active fault and the properties of the surrounding rock. The defense length is determined according to the bending moment distribution, thereby determining the number of lining segments.

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