CN112727502A

CN112727502A - Anti-fault-breakage connecting device for tunnel across fault-fracture zone and construction method of anti-fault-breakage connecting device

Info

Publication number: CN112727502A
Application number: CN202110015231.XA
Authority: CN
Inventors: 汪双杰; 王浩然; 韩常领; 李爽; 周同来
Original assignee: Harbin Institute of Technology; CCCC First Highway Consultants Co Ltd
Current assignee: Harbin Institute of Technology; CCCC First Highway Consultants Co Ltd
Priority date: 2021-01-06
Filing date: 2021-01-06
Publication date: 2021-04-30
Anticipated expiration: 2041-01-06
Also published as: CN112727502B

Abstract

The invention provides a fault-fracture-resistant connecting device for a tunnel across a fault fracture zone and a construction method thereof, wherein the connecting device comprises a primary support, a waterproof layer and a secondary lining which are sequentially arranged from outside to inside, two reinforcing mesh of the primary support are connected through a plurality of hanging ribs, concrete spraying is carried out on the reinforcing mesh parts on two sides, and foam concrete is poured at the fault; two steel bar frameworks of the secondary lining are connected through a plurality of hanging ribs and connecting structures, concrete is poured on the steel bar framework parts on two sides, and foam concrete is poured at a fault. The anti-fault-breakage connecting device and the construction method thereof solve the problem that the prior art does not consider the connection mode of the whole tunnel at the fault, particularly the method of primary support and a waterproof layer in actual construction, and have important practical significance for increasing the stability of tunnel engineering and reducing traffic safety risks.

Description

Anti-fault-breakage connecting device for tunnel across fault-fracture zone and construction method of anti-fault-breakage connecting device

Technical Field

The invention relates to a fault-fracture-resistant connecting device for a tunnel across a fault fracture zone and a construction method of the fault-fracture-resistant connecting device, and belongs to the technical field of tunnel construction.

Background

In order to prevent damage to underground structures caused by adhesion and slippage of faults or long-term creep and slippage of active faults during earthquake, linear structures such as highway tunnels, railway tunnels, water delivery tunnels and the like should be avoided as much as possible during line selection. However, in practical engineering, particularly in the southwest region of China, the tunnel inevitably passes through the active fault due to the limitation of factors such as geological conditions, line trends and construction conditions. Permanent deformation caused by fault dislocation often causes tension, torsional shear and bending damage to the tunnel passing through the permanent deformation, and even serious tunnel causes large-amplitude dislocation or integral collapse.

At present, the research on the mechanical response and the corresponding measures of the tunnel under the action of fault dislocation at home and abroad is endless. A large number of tests and numerical simulation results show that the adoption of the hinged lining is an effective anti-dislocation measure, and the influence of dislocation on the tunnel can be effectively reduced. However, the existing research does not consider the connection mode of the whole tunnel at the fault, especially the way of primary support and waterproof layer in actual construction. Therefore, the anti-fault-breaking connection mode crossing the fault fracture zone tunnel is provided, and the anti-fault-breaking connection mode has important practical significance for increasing the stability of tunnel engineering and reducing traffic safety risks.

Disclosure of Invention

The invention aims to solve the technical problems in the background art and provides a fault-fracture-resistant connecting device for a tunnel across a fault fracture zone and a construction method thereof, which are used for realizing the connection between primary supports and primary supports of tunnels on two sides of a fault and between a secondary lining and a secondary lining so as to meet the requirements in actual design and construction.

The invention provides a fault-breaking-resistant connecting device for a tunnel across a fault-breaking zone, which comprises a primary support, a waterproof layer and a secondary lining which are sequentially arranged from outside to inside,

the primary support comprises two reinforcing mesh, a plurality of I-shaped steel arches, a plurality of hanging ribs and concrete, wherein the two reinforcing mesh and the I-shaped steel arches are both annular, the reinforcing mesh is arranged on the inner wall of the two sides of the cross-section of the tunnel, the reinforcing mesh is supported by the I-shaped steel arches, the two reinforcing mesh are connected through the hanging ribs, concrete spraying is carried out on the reinforcing mesh parts on the two sides, and foam concrete is poured at the cross-section;

the secondary lining comprises two steel bar frameworks, a plurality of hanging ribs, a plurality of connecting structures and concrete, the two steel bar frameworks are connected through the hanging ribs and the connecting structures, concrete is poured on the steel bar frameworks on the two sides, and foam concrete is poured at the fault.

Preferably, the hanging bar comprises two sections of upper straight sections, two sections of inclined long sections and a lower straight section, and the two sections of inclined long sections are connected above two sides of the lower straight section. The two inclined long sections are respectively connected with the two upper straight sections.

Preferably, the reinforcing mesh comprises a plurality of longitudinal steel bars I and a plurality of circumferential steel bars I, and the longitudinal steel bars I and the circumferential steel bars I are mutually vertically bound to form the annular mesh.

Preferably, the steel reinforcement framework comprises a plurality of longitudinal steel bars II, circumferential steel bars II and stirrups, and the plurality of longitudinal steel bars II and the circumferential steel bars II are mutually vertically bound to form a ring-shaped steel reinforcement framework net and are bound and reinforced through the stirrups.

Preferably, the waterproof layer comprises a waterproof board and geotextile, and the waterproof layer is subjected to folding treatment at a fault to ensure that a sufficient deformation margin can be reserved under the action of an earthquake and prevent the waterproof layer from being broken by pulling.

Preferably, the connecting structure comprises two constraint anchoring steel plates and a U-shaped connecting steel plate, the two constraint anchoring steel plates are connected with the steel bar framework, and the middle of the two constraint anchoring steel plates is fixedly connected with the steel bar framework through the U-shaped connecting steel plate.

Preferably, restraint anchor steel sheet includes two anchor steel sheets, diaphragm and a plurality of bolt hole I, install two anchor steel sheets perpendicularly on the diaphragm, be provided with a plurality of bolt holes I on the diaphragm.

Preferably, the U-shaped connecting steel plate comprises a U-shaped steel plate and a plurality of bolt holes II, the two wing plates of the U-shaped steel plate are respectively provided with the bolt holes II, and the number and the position of the bolt holes II correspond to those of the bolt holes I.

A construction method of the anti-fault-breakage connecting device for the tunnel crossing fault-breaking zone specifically comprises the following steps:

(1) binding reinforcing steel bars in the excavated tunnel body on the two sides of the tunnel fault according to the positions shown by the construction drawing, laying a reinforcing mesh, and after the reinforcing mesh is laid, arranging an I-shaped steel arch frame;

(2) hanging bars are uniformly arranged in the circumferential direction among the steel bar nets laid in the holes on the two sides of the fault, the upper straight sections at the two ends of each hanging bar are connected with the steel bar nets in a welding mode, or a certain length is reserved along the longitudinal direction when the longitudinal steel bars I are bound, and the hanging bars are bent into a hanging bar mode and then are connected with the steel bar nets on the other side of the fault in an anchoring mode;

(3) the wet spraying technology is adopted to carry out concrete spraying operation of tunnel primary support, the spraying operation follows the sequence of layering and segmentation from bottom to top, the concrete between the steel arch frames and the wall surface of the tunnel body is sprayed firstly, then the concrete between the two steel arch frames is sprayed, the next layer can be sprayed after the initial setting of the first layer of concrete, no spraying operation is carried out on the fault positions among the steel bar nets in the spraying process, and the fault positions are separated through the templates.

(4) After the concrete injection of the primary tunnel support is finished, pouring foam concrete in the formwork supported at the fault, removing the formwork after the foam concrete is condensed, and finishing all concrete injection and pouring operations of the primary tunnel support;

(5) laying a waterproof layer on the inner wall of the primary support, wherein the waterproof layer adopts a nail-free laying method, the seam of the waterproof layer is formed by adopting an automatic welding seam of a heat sealing machine or is bonded by using special glue, and the waterproof layer is subjected to folding treatment at a fault so as to ensure that enough deformation margin can be reserved under the action of an earthquake and prevent the waterproof layer from being broken;

(6) binding steel bars on the inner walls of the waterproof layers on two sides of the fault according to the positions shown by the construction drawing, and laying a steel bar framework;

(7) hanging bars and constraint anchoring steel plates are uniformly arranged between the steel bar frameworks on the inner wall of the waterproof layer at two sides of the fault in the circumferential direction, wherein the upper straight sections at two ends of each hanging bar are connected with the steel bar frameworks in a welding mode, or a certain length is reserved along the longitudinal direction when a longitudinal steel bar II is bound, the hanging bars are bent into a hanging bar mode and then are in anchoring connection with the steel bar frameworks at the other side of the fault, and the anchoring steel plates of the constraint anchoring steel plates are in welding connection with the steel bar frameworks and are parallel to the hanging bars along the vertical direction;

(8) the lower surfaces of the two wing plate walls of the U-shaped connecting steel plate are tightly attached to the upper surface of the edge of the horizontal plate wall of the constraint anchoring steel plate, so that the bolt hole II is aligned with the bolt hole I, then a high-strength bolt is inserted into the bolt hole II along the bolt hole I in a penetrating manner, and the high-strength bolt is screwed and fixed on the screw part extending out of the lower surface of the constraint anchoring steel plate through a nut;

(9) supporting templates outside the steel reinforcement frameworks on the inner walls of the waterproof layers at two sides of the fault, pouring concrete, removing the templates after the concrete is solidified, wherein no pouring operation is performed at the fault between the steel reinforcement frameworks in the pouring process, and the fault is separated by the templates;

(10) and after the pouring of the secondary lining concrete of the tunnel is finished, pouring foam concrete in the template supported at the fault, and removing the template after the foam concrete is condensed to finish the whole concrete pouring operation of the secondary lining of the tunnel.

Preferably, in step 5, the waterproof board is laid without nails by fixing the geotextile on the primary support surface through the plastic washer and the shooting nails, and then the waterproof board is adhered to the washer by using a special adhesive.

The fault-fracture-resistant connecting device for the cross-fault fracture zone tunnel and the construction method thereof have the beneficial effects that:

1. the primary tunnel support and the secondary lining on two sides of the fault are connected through the hanging ribs, the constraint anchoring steel plates and the U-shaped connecting steel plates. Under the action of an earthquake, when the fault is dislocated, the hanging ribs and the U-shaped connecting steel plate can effectively bear shearing force and bending moment generated when the tunnel is dislocated as main stress components, damage is controlled in a connecting area, and the main body of the tunnel is prevented from being damaged to the maximum extent.

2. The foam concrete is poured in the connecting area of the fault, so that the invention has the advantages of strong waterproofness and good low-elasticity shock absorption, can prevent the hanging ribs and the U-shaped connecting steel plate from being rusted due to environmental factors, can absorb and dissipate energy in earthquake, and enhances the overall shock resistance of the tunnel.

3. In the invention, the waterproof layer between the primary support and the secondary lining is subjected to folding treatment at the fault, so that enough deformation margin can be reserved under the action of an earthquake, and the waterproof layer is prevented from being broken.

4. In the invention, the hanging ribs, the constraint anchoring steel plates and the U-shaped connecting steel plates can be prefabricated in a factory and are installed according to the construction sequence after being transported to the site. When the connection area at the fault is damaged under the action of an earthquake, the foam concrete has the characteristic of low elastic modulus, so that the connection member can be directly repaired or replaced after being chiseled, and the development concept that the current building structure function can be recovered is met.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention.

In the drawings:

fig. 1 is a three-dimensional view of a mesh reinforcement;

FIG. 2 is a three-dimensional view of an I-section steel arch;

FIG. 3 is a three-dimensional view of a hanger bar;

FIG. 4 is a three-dimensional view of the water barrier;

fig. 5 is a three-dimensional view of a rebar skeleton;

FIG. 6 is a three-dimensional view of a constraint anchoring steel plate

FIG. 7 is a three-dimensional view of a U-shaped connecting steel plate;

FIG. 8 is a three-dimensional view of a high tensile bolt;

FIG. 9 is a three-dimensional view of the nut;

fig. 10 is a three-dimensional view of steel mesh and i-beam arch frames arranged in the excavated holes on both sides of the fault;

FIG. 11 is a left side view of the placement of hanger bars between the rebar grids on both sides of a fault;

FIG. 12 is a three-dimensional view of the placement of hanger bars between the rebar grid on both sides of a fault;

FIG. 13 is a three-dimensional view of the completion of the shotcrete of the preliminary bracing of the tunnel;

FIG. 14 is a three-dimensional view of foam concrete poured at a fault between primary supports;

FIG. 15 is a three-dimensional view of a waterproof layer laid on the inner wall of the preliminary bracing;

FIG. 16 is a three-dimensional view of a steel reinforcement cage laid on the inner wall of the waterproof layer on both sides of the fault;

FIG. 17 is a left side view of the placement of hanger bars and constraining anchoring steel plates between the cages on either side of the fault;

FIG. 18 is a three-dimensional view of the placement of hanger bars and constraining anchoring steel plates between the cages on either side of the fault;

FIG. 19 is a left side view of the U-shaped connecting steel plate connected to the restraining anchoring steel plate by high-strength bolts and nuts;

FIG. 20 is a three-dimensional view of the U-shaped connecting steel plate connected with the constraint anchoring steel plate through high-strength bolts and nuts;

FIG. 21 is a three-dimensional view of the completion of casting of the secondary lining concrete of the tunnel;

FIG. 22 is a three-dimensional view of pouring foam concrete at a fault between secondary linings;

wherein, 1-longitudinal steel bar I; 2-circumferential steel bars I; 3-H-shaped steel arch centering; 4-hanging the reinforcement; 5-waterproof layer; 6-longitudinal steel bar II; 7-circumferential reinforcing steel bars II; 8-stirrup; 9-anchoring a steel plate; 10-bolt hole I; 11-U-shaped steel plate; 12-bolt hole II; 13 high-strength bolts; 14-a nut; 15-foam concrete.

Detailed Description

The following detailed description of embodiments of the invention is provided in conjunction with the appended drawings:

the first embodiment is as follows: the present embodiment is explained with reference to fig. 1 to 22. The anti-fault-breakage connecting device for the tunnel across the fault-broken zone comprises a primary support, a waterproof layer 5 and a secondary lining which are sequentially arranged from outside to inside,

the primary support comprises two reinforcing steel bar meshes, a plurality of I-shaped steel arches 3, a plurality of hanging ribs 4 and concrete, wherein the two reinforcing steel bar meshes and the plurality of I-shaped steel arches 3 are both annular, the reinforcing steel bar meshes are arranged on the inner walls of two sides of a cross-section of the tunnel, the reinforcing steel bar meshes are supported by the I-shaped steel arches 3 and are connected by the hanging ribs 4, concrete pouring is carried out on the reinforcing steel bar meshes on two sides, and foam concrete 15 is poured at the cross-section;

the secondary lining comprises two steel bar frameworks, a plurality of hanging ribs 4, a plurality of connecting structures and concrete, the two steel bar frameworks are connected through the hanging ribs 4 and the connecting structures, concrete is poured on the steel bar frameworks on two sides, and foam concrete 15 is poured at a fault.

The connecting structure comprises two constraint anchoring steel plates and a U-shaped connecting steel plate, the two constraint anchoring steel plates are connected with the steel reinforcement framework, and the middle of the two constraint anchoring steel plates is fixedly connected with the steel reinforcement framework through the U-shaped connecting steel plate.

(1) As shown in fig. 1, the concrete structure of the mesh reinforcement is as follows:

the reinforcing mesh (figure 1) is composed of longitudinal reinforcing steel bars I1 and circumferential reinforcing steel bars I2.

1. Longitudinal reinforcement I1 and hoop reinforcement I2 need carry out the ligature according to the position that the construction drawing shows, ligature hoop reinforcement I2 earlier, back ligature longitudinal reinforcement I1, and mutually perpendicular weaves the looped netowrk.

The type, the diameter and the interval of the longitudinal steel bar I1 and the circumferential steel bar I2 are determined according to design requirements.

(2) As shown in fig. 2, the specific structure of the i-shaped steel arch is as follows:

the I-shaped steel arch frame 3 is cut into sections according to the section size set by the tunnel body excavation scheme, and is manufactured by blanking, sectioning and welding outside the tunnel. During welding, accurate machining is carried out strictly according to the measurement lofting size, the whole arc is smooth after the steel arch is installed and formed, the axes of adjacent sections at the joint are overlapped, and the position of the connecting hole is accurate, so that the structural stress performance of the steel arch is ensured.

(3) As shown in fig. 3, the concrete structure of the hanging bar is as follows:

the hanging bar 4 is composed of two sections of an upper straight section, two sections of an inclined long section and a lower straight section.

The length of the upper straight section is determined by the diameter of the lifting rib 4.

The starting angle of the two inclined long sections is determined by the thickness of the concrete layer of the primary tunnel support and the secondary lining.

The length of the lower straight section is determined by the fault width.

The type and the diameter of the hanging bar 4 are determined according to the shearing force born by the primary tunnel support and the secondary lining in the anti-dislocation process.

(4) As shown in fig. 4, the waterproof layer has the following specific structure:

the waterproof layer 5 is composed of a waterproof board and geotextile.

The waterproof layer 5 should be subjected to folding treatment at the fault position to ensure that a sufficient deformation margin can be reserved under the action of an earthquake, so that the waterproof layer is prevented from being broken by pulling.

(5) As shown in fig. 5, the concrete structure of the steel reinforcement framework is as follows:

the steel bar framework consists of a longitudinal steel bar II 6, a circumferential steel bar II 7 and a stirrup 8.

And the longitudinal steel bar II 6, the circumferential steel bar II 7 and the stirrup 8 need to be bound according to the positions shown in the construction drawing, the circumferential steel bar II 7 is bound firstly, the longitudinal steel bar II 6 is bound, and the stirrup 8 is bound finally.

The types, the diameters and the intervals of the longitudinal steel bars II 6, the circumferential steel bars II 7 and the stirrups 8 are determined according to design requirements.

(6) As shown in fig. 6, the specific structure of the constraint anchor steel plate is as follows:

the constraint anchor steel plate (figure 6) is composed of an anchor steel plate 9 and a bolt hole I10.

The bolt holes I10 are formed in the edge area of the horizontal plate wall of the anchoring steel plate 9 in a double-sided through drilling mode, and the number and the size of the bolt holes I10 are determined by the number and the size of high-strength bolts 13 penetrating through the holes.

The size of the anchoring steel plate 9 is determined by the thickness of the concrete layer of the secondary lining of the tunnel and the bending moment born by the secondary lining in the case of dislocation resistance.

(7) As shown in fig. 7, the specific structure of the U-shaped connecting steel plate is as follows:

the U-shaped connecting steel plate (figure 7) consists of a U-shaped steel plate 11 and a bolt hole II 12.

Bolt holes II 12 are formed in the horizontal plate wall areas of the two wings of the U-shaped steel plate 11 in a double-face through drilling mode, and the positions, the number and the sizes of the bolt holes II 12 are determined by the positions, the number and the sizes of the bolt holes I10.

The size of the U-shaped steel plate 11 is determined by the fault width and the bending moment born by the secondary lining of the tunnel in the fault fracture resistance.

(8) As shown in fig. 8-9, the specific structure and manufacturing process of the high-strength bolt and nut are as follows:

the number of the high-strength bolts 13 and the outer diameter of the screw are determined according to design requirements.

The length of the screw rod of the high-strength bolt 13 is not less than the sum of the thickness of the horizontal plate wall of the constraint anchoring steel plate (figure 6), the thickness of the horizontal plate wall of the two wings of the U-shaped connecting steel plate (figure 7) and the thickness of the nut 14.

The size of the nut 14 is determined by the outer diameter of the high-tensile bolt 13.

After the materials and the components are prepared, the construction operation of the tunnel is carried out according to the sequence of primary support, a waterproof layer and secondary lining:

(1) as shown in fig. 10, reinforcing steel bars are bound in the excavated tunnel bodies (the tunnel bodies are not shown for avoiding pattern shielding) on two sides of the fault according to the positions shown in the construction drawing, and reinforcing mesh is laid (fig. 1). After the reinforcing mesh (figure 1) is laid, the I-shaped steel arch frame 3 is arranged.

(2) As shown in fig. 11 and 12, the hanging bars 4 are arranged at regular intervals between the reinforcing steel bar nets (fig. 1) laid in the holes on both sides of the fault according to design requirements, the upper straight sections at both ends of the hanging bars 4 can be connected with the reinforcing steel bar nets (fig. 1) in a welding manner, or a certain length can be reserved along the longitudinal direction when the longitudinal steel bars i 1 are bound, and the hanging bars are bent into the form and then are connected with the reinforcing steel bar nets (fig. 1) on the other side of the fault in an anchoring manner.

(3) As shown in fig. 13, the concrete spraying work for preliminary tunnel support is performed by the wet spraying technique. The spraying operation follows the sequence of layering and segmenting from bottom to top, the concrete between the steel arch frames and the wall surface of the hole body is sprayed firstly, then the concrete between the two steel arch frames is sprayed, and the next layer can be sprayed after the first layer of concrete is initially set. In the spraying process, no spraying operation is carried out on the fault positions among the reinforcing meshes (shown in figure 1), and the fault positions are separated by the templates.

(4) As shown in fig. 14, after the concrete injection of the tunnel preliminary bracing is completed, foam concrete 15 is poured into the formwork supported at the fault, and after the foam concrete is solidified, the formwork is removed, thereby completing all the concrete injection and pouring operations of the tunnel preliminary bracing.

(5) As shown in fig. 15, a waterproof layer 5 is laid on the inner wall of the preliminary bracing, and the waterproof layer 5 is composed of a waterproof board and geotextile. The waterproof board adopts a nail-free laying method, namely, the geotextile is fixed on the surface of the primary support through the plastic washer and the shooting nail, and then the waterproof board is adhered on the washer by using a special adhesive. The joint of the waterproof board can be formed by automatic welding seams of a heat sealing machine or bonded by special glue. The waterproof layer 5 should be subjected to folding treatment at the fault position to ensure that a sufficient deformation margin can be reserved under the action of an earthquake, so that the waterproof layer is prevented from being broken by pulling.

(6) As shown in fig. 16, reinforcing steel bars are bound on the inner walls of the waterproof layers 5 (the waterproof layers 5 are not shown for avoiding pattern shielding) on two sides of the fault according to the positions shown in the construction drawing, and a reinforcing steel bar framework is laid (fig. 5).

(7) As shown in fig. 17 and 18, hanging bars 4 and restraining anchor steel plates (fig. 6) are arranged between the reinforcement cages (fig. 5) on the inner walls of the waterproof layers 5 on both sides of the fault at regular intervals according to design requirements. The upper straight sections at the two ends of the hanging rib 4 can be connected with the steel bar framework (shown in figure 5) in a welding mode, and can also be longitudinally reserved for a certain length when a longitudinal steel bar II 6 is bound, and are connected with the steel bar framework (shown in figure 5) on the other side of the fault in an anchoring mode after being bent into a hanging rib mode. The vertical flange of the constraint anchoring steel plate (figure 6) is welded with the steel reinforcement framework (figure 5) and is parallel to the hanging bar 4 along the vertical direction.

(8) As shown in fig. 19 and 20, the lower surfaces of the two wing plate walls of the U-shaped connecting steel plate (fig. 7) are tightly attached to the upper surface of the edge of the horizontal plate wall of the restraining and anchoring steel plate (fig. 6) to ensure that the bolt holes ii 12 and i 10 are aligned, then the high-strength bolts 13 are inserted through the bolt holes ii 12 and i 10, and the high-strength bolts 13 are fastened and fixed by nuts 14 at the screw portions protruding from the lower surface of the restraining and anchoring steel plate (fig. 6).

(9) As shown in fig. 21, the formwork is supported outside the steel reinforcement framework (fig. 5) on the inner wall of the waterproof layer 5 on both sides of the fault, concrete is poured, and the formwork is removed after the concrete is solidified. In the pouring process, no pouring operation is performed on the fault positions among the steel reinforcement frameworks (shown in figure 5), and the fault positions are separated through the templates.

(10) As shown in fig. 22, after the pouring of the secondary lining concrete of the tunnel is completed, foam concrete 15 is poured into the formwork supported at the fault, and after the foam concrete is condensed, the formwork is removed, so that the whole concrete pouring operation of the secondary lining of the tunnel is completed.

In the embodiment, the tunnel primary support and the secondary lining on two sides of the fault are connected through the hanging ribs 4, the constraint anchoring steel plates (figure 6) and the U-shaped connecting steel plates (figure 7). Under the action of earthquake, when the fault is dislocated, the hanging ribs 4 and the U-shaped connecting steel plate (figure 7) can effectively bear shearing force and bending moment generated when the tunnel is dislocated, damage is controlled in a connecting area, and the main body of the tunnel is prevented from being damaged to the maximum extent.

In this embodiment, the foam concrete 15 poured in the connection area at the fault has the advantages of strong waterproofness and good low-elasticity shock absorption, and can prevent the hanging bar 4 and the U-shaped connecting steel plate (fig. 7) from being rusted due to environmental factors, absorb and dissipate energy during an earthquake, and enhance the overall earthquake resistance of the tunnel.

In this embodiment, the waterproof layer 5 between the primary support and the secondary lining is wrinkled at the fault, so that a sufficient deformation margin can be reserved under the action of an earthquake, and the waterproof layer is prevented from being broken by tension.

In this embodiment, the suspension bar 4, the constraint anchoring steel plate (fig. 6) and the U-shaped connecting steel plate (fig. 7) can be prefabricated in a factory and installed according to the construction sequence after being transported to the site. When the connection area at the fault is damaged under the action of an earthquake, the foam concrete has the characteristic of low elastic modulus, so that the connection member can be directly repaired or replaced after being chiseled, and the development concept that the current building structure function can be recovered is met.

The above-mentioned embodiments further explain the objects, technical solutions and advantages of the present invention in detail. It should be understood that the above-mentioned embodiments are only examples of the present invention, and are not intended to limit the present invention, and that the reasonable combination of the features described in the above-mentioned embodiments can be made, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A fault-fracture-resistant connecting device for a tunnel across a fault-fracture zone is characterized by comprising a primary support, a waterproof layer (5) and a secondary lining which are sequentially arranged from outside to inside,

the primary support comprises two reinforcing steel bar nets, a plurality of I-shaped steel arch frames (3), a plurality of hanging ribs (4) and concrete, wherein the two reinforcing steel bar nets and the plurality of I-shaped steel arch frames (3) are annular, the reinforcing steel bar nets are arranged on the inner walls of two sides of a cross section of the tunnel, the reinforcing steel bar nets are supported through the I-shaped steel arch frames (3), the two reinforcing steel bar nets are connected through the hanging ribs (4), concrete spraying is carried out on the reinforcing steel bar net parts on two sides, and foam concrete (15) is poured at the cross section;

the secondary lining comprises two steel bar frameworks, a plurality of hanging ribs (4), a plurality of connecting structures and concrete, the two steel bar frameworks are connected through the hanging ribs (4) and the connecting structures, concrete is poured on the steel bar frameworks on two sides, and foam concrete (15) is poured at a fault.

2. The cross-fault-fracture-zone tunnel anti-fault-fracture connecting device according to claim 1, wherein the hanging rib (4) comprises two sections of an upper straight section, two sections of inclined long sections and a lower straight section, and the two sections of inclined long sections are connected above two sides of the lower straight section. The two inclined long sections are respectively connected with the two upper straight sections.

3. The anti-fault-breaking connecting device for the cross-fault fracture zone tunnel according to claim 1, wherein the reinforcing mesh comprises a plurality of longitudinal reinforcing steel bars I (1) and circumferential reinforcing steel bars I (2), and the longitudinal reinforcing steel bars I (1) and the circumferential reinforcing steel bars I (2) are vertically bound to each other to form an annular mesh.

4. The anti-fault-breakage connecting device for the cross-fault fracture zone tunnel according to claim 1, wherein the steel reinforcement framework comprises a plurality of longitudinal steel reinforcements II (6), circumferential steel reinforcements II (7) and stirrups (8), the longitudinal steel reinforcements II (6) and the circumferential steel reinforcements II (7) are mutually perpendicularly bound to form an annular steel reinforcement framework net, and binding and reinforcement are carried out through the stirrups (8).

5. The cross-fault fracture zone tunnel anti-fault-fracture connection device according to claim 1, characterized in that the waterproof layer (5) comprises waterproof boards and geotextiles, and the waterproof layer (5) is subjected to a folding treatment at the fault to ensure that a sufficient deformation margin can be reserved under the action of an earthquake to prevent the waterproof layer from being broken.

6. The cross-fault-fracture-zone tunnel anti-fault-fracture connecting device of claim 1, wherein the connecting structure comprises two constraint anchoring steel plates and a U-shaped connecting steel plate, the two constraint anchoring steel plates are connected with the steel reinforcement framework, and the middle of the two constraint anchoring steel plates is fixedly connected through the U-shaped connecting steel plate.

7. The cross-fault-broken-zone tunnel anti-fault-breakage connecting device according to claim 6, characterized in that the constraint anchoring steel plates comprise two anchoring steel plates (9), a transverse plate and a plurality of bolt holes I (10), the transverse plate is vertically provided with the two anchoring steel plates (9), and the transverse plate is provided with the plurality of bolt holes I (10).

8. The tunnel fault-breaking-resistant connecting device across the fault-breaking zone according to claim 7, wherein the U-shaped connecting steel plate comprises a U-shaped steel plate (11) and a plurality of bolt holes II (12), the bolt holes II (12) are respectively arranged on two wing plates of the U-shaped steel plate (11), and the number and the position of the bolt holes II (12) correspond to those of the bolt holes I (10).

9. A construction method of the anti-fault-breaking connecting device for the cross-fault fracture zone tunnel according to any one of claims 1 to 8, characterized by comprising the following steps:

(1) binding reinforcing steel bars in the excavated tunnel body on the two sides of the tunnel fault according to the positions shown by the construction drawing, laying a reinforcing mesh, and after the reinforcing mesh is laid, arranging an I-shaped steel arch frame (3);

(2) hanging ribs (4) are uniformly arranged between the steel bar nets laid in the holes on the two sides of the fault in the circumferential direction, upper straight sections at the two ends of each hanging rib (4) are connected with the steel bar nets in a welding mode, or a certain length is reserved along the longitudinal direction when longitudinal steel bars I (1) are bound, and the hanging ribs are bent into a hanging rib mode and then connected with the steel bar nets on the other side of the fault in an anchoring mode;

(4) After the concrete injection of the primary tunnel support is finished, pouring foam concrete (15) in the formwork supported at the fault, removing the formwork after the foam concrete is condensed, and finishing all concrete injection and pouring operations of the primary tunnel support;

(5) a waterproof layer (5) is laid on the inner wall of the primary support, the waterproof layer adopts a nail-free laying method, the seam of the waterproof layer is formed by adopting an automatic welding seam of a heat sealing machine or is bonded by using special glue, and the waterproof layer (5) is subjected to folding treatment at a fault so as to ensure that enough deformation margin can be reserved under the action of an earthquake and prevent the waterproof layer from being broken by pulling;

(6) binding steel bars on the inner walls of the waterproof layers (5) on two sides of the fault according to the positions shown by the construction drawing, and laying a steel bar framework;

(7) hanging ribs (4) and restraining and anchoring steel plates are uniformly arranged between rib frameworks on the inner wall of the waterproof layer (5) on two sides of the fault in the circumferential direction, wherein upper straight sections at two ends of each hanging rib (4) are connected with the rib frameworks in a welding mode, or a certain length is reserved along the longitudinal direction when longitudinal steel bars II (6) are bound, the hanging ribs are bent into a hanging rib mode and then are in anchoring connection with the rib frameworks on the other side of the fault, and the anchoring steel plates (9) of the restraining and anchoring steel plates are in welding connection with the rib frameworks and are parallel to the hanging ribs (4) in the vertical direction;

(8) the lower surfaces of two wing plate walls of the U-shaped connecting steel plate are tightly attached to the upper surface of the edge of a horizontal plate wall of the constraint anchoring steel plate, so that the bolt hole II (12) is aligned with the bolt hole I (10), then a high-strength bolt (13) is inserted in a penetrating manner along the bolt hole II (12) and the bolt hole I (10), and the high-strength bolt (13) is screwed and fixed on a screw part extending out of the lower surface of the constraint anchoring steel plate through a nut 14;

(9) supporting templates outside the steel reinforcement frameworks on the inner walls of the waterproof layers (5) at two sides of the fault, pouring concrete, removing the templates after the concrete is solidified, wherein no pouring operation is performed at the fault between the steel reinforcement frameworks in the pouring process, and the fault is separated by the templates;

(10) and after the secondary lining concrete of the tunnel is poured, pouring foam concrete (15) in the template supported at the fault, and removing the template after the foam concrete is condensed to finish all concrete pouring operation of the secondary lining of the tunnel.

10. The method for constructing the anti-fault-breaking connecting device of the cross-fault fracture zone tunnel of claim 9, wherein in the step 5, the waterproof board is laid without nails by fixing the geotextile on the primary supporting surface through a plastic washer and a nail and then adhering the waterproof board on the washer by using a special adhesive.