Tunnel non-vertical crossing construction adit structure and construction method

Abstract

The invention discloses a tunnel non-perpendicular crossing construction adit structure and a construction method, and the tunnel non-perpendicular crossing construction adit structure comprises a main tunnel, an adit and a supporting module; the main tunnel is communicated with the branch tunnels, and tunnel intersections are formed at the joints of the main tunnel and the branch tunnels; each branch hole is obliquely arranged relative to the main hole, the connecting position of each branch hole and the main hole is of an opening-shaped structure, and correspondingly, the opening-shaped structure, the tunnel intersection and one branch hole form a steering space; the number of the supporting modules is at least three, and each supporting module is arranged in the main hole or the branch hole. The construction method is used for construction of the tunnel non-vertical crossing construction adit structure. Through the arrangement of the opening-shaped structure, the problem that a tunnel bottom plate is narrow is solved, the turning radius is increased, turning and direction turning of a construction vehicle are facilitated, mutual interference of cross construction in a tunnel is greatly reduced, and the construction efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of tunnel engineering construction, and in particular to a tunnel non-vertical cross construction branch tunnel structure and a construction method. Background Art

[0002] A hydraulic tunnel is a water tunnel dug in a mountain or underground that can be used for irrigation, power generation, water supply, water discharge, water transfer, construction diversion and navigation.

[0003] Most of the existing hydraulic tunnels are circular after lining, and the bottom plate is relatively narrow. For example, the width of a hydraulic tunnel with a diameter of 8.1m is only 3.2m. Based on this, during the construction of hydraulic tunnels, due to its narrow width, it is not convenient for construction vehicles to travel in both directions, and the cross-construction in the tunnel interferes with each other, affecting the progress and efficiency of the construction, and increasing the construction time and cost. Summary of the invention

[0004] The technical problem to be solved by the present invention is that the existing hydraulic tunnel is narrow in width and affects the driving of construction vehicles. The purpose is to provide a tunnel non-vertical cross construction branch tunnel structure and construction method to solve the above problem.

[0005] The present invention is achieved through the following technical solutions:

[0006] In a first aspect, the present invention provides a tunnel non-vertical cross construction branch tunnel structure, comprising a main tunnel, a branch tunnel and a support module;

[0007] The main tunnel is connected to the branch tunnel, the connection between the main tunnel and the branch tunnel forms a tunnel intersection, and there are at least two branch tunnels;

[0008] Each branch tunnel is inclined relative to the main tunnel, and the connection between each branch tunnel and the main tunnel is constructed as an open structure. Accordingly, the open structure, the tunnel intersection and one of the branch tunnels form a turning space for the equipment to turn around.

[0009] There are at least three groups of support modules, and each group of support modules is respectively arranged in the main tunnel or the branch tunnel. Correspondingly, a support beam is provided at the arch axis of the main tunnel, and the support beam extends to the intersection of the tunnels and connects each group of support modules.

[0010] In one possible design, the main hole and the branch hole have an acute angle between them;

[0011] In each branch hole, the opening structure includes an outward expansion section and a chamfer. Correspondingly, the outward expansion section and the chamfer are respectively located on both sides of the branch hole, and the outward expansion section is far away from the included angle, and the chamfer is close to the included angle.

[0012] In a possible design, the branch tunnel includes an expanded branch tunnel, a diverted branch tunnel and at least one additional branch tunnel;

[0013] The expanded branch tunnel has two ends, one of which is connected to the main tunnel, and the other end extends upward and connects to the outside. Accordingly, at least two gentle slopes with a slope of 2.5%-3.5% and multiple anti-collision piers are provided in the expanded branch tunnel;

[0014] The turning branch tunnel and the additional branch tunnel are both arranged underground, and correspondingly, a plurality of crash piers are respectively arranged at the opening structures of the turning branch tunnel and the additional branch tunnel.

[0015] In one possible design, the support module includes a first arch frame arranged along the main hole and a second arch frame arranged along the branch hole;

[0016] The first arches are evenly distributed in the main hole, and the distance between two adjacent first arches is no more than 50cm;

[0017] The second arch frame is divided into at least two support groups and is respectively arranged in one of the branch holes. Accordingly, the support groups and the branch holes are arranged in one-to-one correspondence;

[0018] Each support group includes a plurality of second arch frames, wherein the second arch frames located in the tunnel body of the branch tunnel are arranged at equal intervals, and the second arch frames located in the open structure are arranged at intervals, and one end of the second arch frames is connected to the chamfer and the other end is connected to the expansion section.

[0019] In a possible design, the distance between two adjacent second arches located in the open structure at one end connected to the chamfer is no more than 50 cm, and the distance between two adjacent second arches located in the open structure at one end connected to the expansion section is no more than 120 cm;

[0020] In the second arch frame located in the open structure, the second arch frame located at the outermost side is connected to the first arch frame and is perpendicular to the first arch frame.

[0021] In a possible design, positioning ties are provided around the support modules, one end of the positioning ties is connected to the adjacent support modules, and the other end of the positioning ties is anchored 0.5-1m into the tunnel surrounding rock; and a mortar layer is provided around each positioning ties;

[0022] A plurality of anchor rods are provided on both sides of the bottom of each support module, and the anchor rods are connected to the support module to form a leg locking device; a plurality of reinforcing ribs are provided in the horizontal direction of each support module, and each reinforcing rib is connected to the support module and anchored into the surrounding rock of the tunnel;

[0023] Reinforcement columns are provided at the gaps between the joists and the supporting modules.

[0024] In a second aspect, the present invention provides a construction method for the non-vertical cross-construction branch tunnel structure of the tunnel, comprising the following steps:

[0025] S1 tunnel construction: cross-section construction interval division; expansion and excavation of branch tunnels, excavation to the main tunnel; main tunnel construction; after the settlement of the tunnel intersection converges and stabilizes, the remaining branch tunnels are constructed;

[0026] S2 support construction: During tunnel construction, steel mesh is processed into pieces outside the tunnel; as the tunnel is excavated, steel mesh is laid and welded inside the tunnel; positioning tie bars and anchor rods are constructed; the first arch frame and the second arch frame are installed along the positioning tie bars;

[0027] S3 arch pipe shed construction: construct guide steel pipes along the tunnel excavation contour and form guide walls;

[0028] S4 mesh spraying support construction and lining construction.

[0029] In a possible design, in S1, when the branch tunnel is excavated to the main tunnel, a tunnel with a staggered distance of not less than 8m is excavated to serve as the main tunnel body and construction guide tunnel; before the construction of the tunnel intersection, shrinkage anchor support is applied.

[0030] In one possible design, in S1, the construction of the opening structure includes the following steps:

[0031] S100 middle guide tunnel construction: dig the middle guide tunnel obliquely upward to the top of the middle guide tunnel; expand and dig the top of the middle guide tunnel to form it; expand and dig the middle guide tunnel downward to form it;

[0032] Construction of the rest of S200: from top to bottom, construct the lower step and bottom protective layer respectively;

[0033] S300 repeats S100 and S200 to complete the construction of the expansion section and chamfer respectively.

[0034] In a possible design, during the construction of the open structure, the cycle advance is no more than 3m; during the excavation of the middle guide tunnel, the tunnel face is backfilled with slag in layers.

[0035] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0036] The setting of an open structure solves the problem of narrow tunnel floor, increases the turning radius, and facilitates construction vehicles to turn and change direction, making the driving of construction vehicles in the tunnel more flexible, greatly reducing the mutual interference of cross-construction in the tunnel, and improving construction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other relevant drawings can be obtained based on these drawings without creative work. In the drawings:

[0038] Figure 1It is a structural schematic diagram of a tunnel non-vertical cross construction branch tunnel structure.

[0039] Figure 2 Schematic diagram of the connection between the expanded branch tunnel and the main tunnel.

[0040] Figure 3 It is a flow chart of a construction method for the non-vertical cross-construction branch tunnel structure of the tunnel.

[0041] Marks and corresponding parts names in the attached drawings:

[0042] 100, main tunnel; 200, branch tunnel; 201, expanded branch tunnel; 202, turning branch tunnel; 300, support module; 400, tunnel intersection; 500, open structure; 501, outward expansion section; 502, chamfer. DETAILED DESCRIPTION

[0043] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0044] In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present invention. However, it is apparent to one of ordinary skill in the art that these specific details are not necessarily employed to practice the present invention. In other embodiments, in order to avoid obscuring the present invention, well-known structures, circuits, materials, or methods are not specifically described.

[0045] Throughout the specification, references to "one embodiment," "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in conjunction with the embodiment or example is included in at least one embodiment of the present invention. Therefore, the phrases "one embodiment," "an embodiment," "an example," or "an example" appearing in various places throughout the specification do not necessarily all refer to the same embodiment or example. In addition, particular features, structures, or characteristics may be combined in one or more embodiments or examples in any suitable combination and / or sub-combination. In addition, it will be appreciated by those of ordinary skill in the art that the figures provided herein are for illustrative purposes and that the figures are not necessarily drawn to scale. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0046] In the description of the present invention, the directions or positional relationships indicated by terms such as “front”, “rear”, “left”, “right”, “up”, “down”, “vertical”, “horizontal”, “high”, “low”, “inside” and “outside” are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limiting the scope of protection of the present invention.

[0047] Embodiment 1:

[0048] Take construction vehicles as an example. When the size of the construction vehicles is large and the width of the tunnel is narrow, the construction vehicles can travel in one direction, but it is difficult for the construction vehicles to change their direction, and it is impossible to achieve two-way travel in the tunnel. In the construction process of the tunnel, there are multi-directional cross-constructions. In this case, construction is difficult. Based on this, a non-vertical cross-construction branch tunnel structure is provided, specifically:

[0049] like Figure 1 and Figure 2 As shown, a tunnel non-vertical cross construction branch tunnel structure includes a main tunnel 100, a branch tunnel 200 and a support module 300;

[0050] The main tunnel 100 is connected to the branch tunnel 200, and the connection between the main tunnel 100 and the branch tunnel 200 forms a tunnel intersection 400, and the branch tunnel 200 is provided with at least two;

[0051] Each branch hole 200 is inclined relative to the main hole 100, and the connection between each branch hole 200 and the main hole 100 is constructed as an open structure 500. Accordingly, the open structure 500, the tunnel intersection 400 and one of the branch holes 200 form a turning space for the equipment to turn around.

[0052] There are at least three groups of support modules 300, and each group of support modules 300 is respectively arranged in the main tunnel 100 or the branch tunnel 200. Accordingly, a joist is provided at the arch axis of the main tunnel 100, and the joist extends to the tunnel intersection 400 and connects each group of support modules 300.

[0053] In the non-vertical cross-construction branch tunnel structure of the tunnel, at least two branch tunnels 200 are provided, one of which is configured as an expanded branch tunnel 201, and the other is configured as a turning branch tunnel 202. The expanded branch tunnel 201 is configured as an inclined passage connecting to the outside world. The staff excavates the expanded branch tunnel 201 from the ground downward until the expanded branch tunnel 201 extends to the designed main tunnel 100 position. Based on this, the main tunnel 100 is constructed.

[0054] Furthermore, there is a large space at the connection between the main tunnel 100 and the expanded branch tunnel 201, where a branch tunnel can be constructed. On the one hand, the volume of the connection is enlarged to form a tunnel intersection 400, and on the other hand, the branch tunnel is used as a turning branch tunnel 202 for construction vehicles to turn. Combined with the larger space at the tunnel intersection 400, the turning of the construction vehicle is realized, and the construction vehicle is prevented from bumping into the tunnel and / or the supporting structure inside the tunnel during the turning process.

[0055] In addition, when there are multiple construction vehicles in the tunnel, the expanded branch tunnel 201 and the turning branch tunnel 202 can be used to temporarily park the construction vehicles so that the remaining construction vehicles can pass through in time, thus facilitating the meeting of multiple construction vehicles.

[0056] It is worth noting that in order to improve the convenience and safety of turning of construction vehicles, the structure of the branch tunnel 200 is further improved, that is, each branch tunnel 200 is inclined relative to the main tunnel 100, and the connection between each branch tunnel 200 and the main tunnel 100 is constructed as an open structure 500. Based on this, the branch tunnel 200 is inclined, and the connection between the two sides of the branch tunnel 200 and the main tunnel 100 is an acute angle on one side and an obtuse angle on the other side. After the opening structure 500 is applied, on the one hand, the acute angle is eliminated to ensure the stability of the tunnel structure and ensure construction safety, and on the other hand, the space is increased, and the driving and turning of the construction vehicles are more convenient.

[0057] At the same time, when the construction vehicle needs to change its driving direction, the construction vehicle can be guided into the expanded branch hole 201 or the turning branch hole 202 from the opening structure 500, thereby enlarging the turning radius, reducing the turning angle of the construction vehicle, and avoiding collision of the construction vehicle.

[0058] Furthermore, in theory, both the expanded branch tunnel 201 and the turning branch tunnel 202 can be used for the turning of construction vehicles. However, since the expanded branch tunnel 201 is inclined and other construction vehicles enter the main tunnel 100 from the expanded branch tunnel 201, turning is not only difficult but also involves safety risks. Therefore, when turning, construction vehicles preferably drive into the turning branch tunnel 202.

[0059] After the tunnel is excavated, the support module 300 is promptly applied to form the initial support through the support module 300 to ensure that the tunnel structure strength and safety meet the construction requirements and ensure construction safety. At the same time, the support modules 300 in each tunnel are connected by a joist so that each support module 300 is connected as a whole, and the support effect is better. It is easy to understand that if the tunnel needs to be expanded, the support module 300 is preferably temporarily supported by any appropriate temporary support to avoid interfering with the subsequent expansion operation.

[0060] It is easy to understand that in addition to construction vehicles, any other suitable construction equipment can also pass through the non-vertical cross construction branch tunnel structure of the tunnel.

[0061] In a possible implementation, the main hole 100 and the branch hole 200 have an acute angle therebetween;

[0062] In each branch hole 200 , the opening structure 500 includes an outward expansion section 501 and a chamfer 502 . Accordingly, the outward expansion section 501 and the chamfer 502 are located on both sides of the branch hole 200 , respectively, and the outward expansion section 501 is far away from the included angle, while the chamfer 502 is close to the included angle.

[0063] Based on the above design scheme, the branch tunnel 200 is inclined, so when the construction vehicle turns, the turning radius of the construction vehicle is larger, which makes it easier for the construction vehicle to turn and change direction. However, at this time, the connection between the two sides of the branch tunnel 200 and the main tunnel 100 is an acute angle on one side and an obtuse angle on the other side. There are disturbances during the tunnel construction process. Under the action of disturbances, the acute angle is prone to instability and breakage, resulting in safety hazards in the tunnel. Based on this, a chamfer 502 is applied on one side of the acute angle to ensure the safety of the structure and to expand the space on this side as much as possible for the construction vehicle to turn. On the obtuse angle side, an outward expansion section 501 can be applied, and the construction vehicle gives priority to using the outward expansion section 501 when turning.

[0064] Alternatively, if Figure 1 As shown, in the expanded branch tunnel 201 and the turning branch tunnel 202, the connections between the two and the main tunnel 100 are arranged opposite to each other, and the outward expansion sections 501 of the two are arranged opposite to each other, and the chamfers 502 of the two are arranged opposite to each other; or, in the expanded branch tunnel 201 and the turning branch tunnel 202, the connections between the two and the main tunnel 100 are staggered, so that the outward expansion section 501 of one of them faces the chamfer 502 of the other.

[0065] Therefore, the layout of the expanded branch hole 201 and the diverted branch hole 202 is varied to adapt to different construction conditions and has good practicality. It is easy to understand that the construction personnel arrange the positions of the expanded branch hole 201 and the diverted branch hole 202 according to the actual construction conditions, and the present invention does not impose any restrictions on this.

[0066] It is easy to understand that, on the basis of ensuring the stability of the tunnel structure and facilitating the turning of the construction vehicles, the expansion section 501 can be constructed into any suitable shape. Similarly, the chamfer 502 can be constructed into any suitable angle.

[0067] In a possible implementation, the branch tunnel 200 includes an expanded branch tunnel 201, a diverted branch tunnel 202, and at least one additional branch tunnel 200;

[0068] The expanded branch tunnel 201 has two ends, one of which is connected to the main tunnel 100, and the other end extends upward and is connected to the outside. Accordingly, at least two gentle slopes with a slope of 2.5%-3.5% and a plurality of anti-collision piers are provided in the expanded branch tunnel 201;

[0069] The turning branch hole 202 and the additional branch hole 200 are both arranged underground. Accordingly, a plurality of crash barriers are respectively arranged at the opening structures 500 of the turning branch hole 202 and the additional branch hole 200 .

[0070] Based on the above design scheme, for the branch tunnel 200, in addition to expanding the branch tunnel 201 and turning the branch tunnel 202, additional branch tunnels 200 can also be set according to construction needs to meet the corresponding construction needs. On the basis of ensuring the safety of the tunnel structure, the connection between the additional branch tunnel 200 and the main tunnel 100 is preferably at the tunnel intersection 400 and the adjacent tunnel intersection 400.

[0071] As for the expanded branch tunnel 201, since it is connected to the ground, the slope is relatively large. Then, when the construction vehicle drives down along the expanded branch tunnel 201, it is easy to have a high speed, and the traffic safety is poor. Therefore, a gentle slope with a small slope is set in the expanded branch tunnel 201 to allow the driver to reduce the speed in time, improve the control of the vehicle, and ensure traffic safety. At the same time, with the help of anti-collision piers, if the construction vehicle loses control, it is preferred to hit the anti-collision pier to protect the tunnel and minimize the damage to the tunnel.

[0072] Similarly, the main tunnel 100 and the remaining branch tunnels 200 are located underground, and their slopes are relatively gentle, so the driving controllability of construction vehicles is better. At this time, construction vehicles are prone to bumping when turning. For the turning branch tunnel 202 and the additional branch tunnel 200, it is only necessary to set anti-collision piers at the opening structure 500.

[0073] In a possible implementation, the support module 300 includes a first arch frame arranged along the main hole 100 and a second arch frame arranged along the branch hole 200;

[0074] The first arch frames are evenly distributed in the main hole 100, and the distance between two adjacent first arch frames is no more than 50 cm;

[0075] The second arch frame is divided into at least two support groups and is respectively arranged in one of the branch holes 200. Accordingly, at least two branch holes 200 are provided;

[0076] Each support group includes a plurality of second arch frames, wherein the second arch frames located in the body of the branch cave 200 are arranged at equal intervals, and the second arch frames located in the open structure 500 are arranged at intervals, and one end of each arch frame is connected to the chamfer 502 and the other end is connected to the expansion section 501.

[0077] Based on the above design, for the branch tunnel 200, since the branch tunnel 200 is inclined relative to the main tunnel 100, and the opening structure 500 has a certain arc due to the setting of the expansion section 501, in order to ensure the supporting effect of the arch frame, the second arch frame is set at an equal angle at the opening structure 500 with the center of the arc as the center. On the contrary, for other sections of the tunnel, such as the main tunnel 100 and the branch tunnel 200 area without the opening structure 500, it is preferred to use an equal spacing setting to ensure the supporting effect.

[0078] Optionally, between two adjacent second arches located in the open structure 500 , the distance between the ends connecting the chamfer 502 is no more than 50 cm, and the distance between the ends connecting the outward expansion section 501 is no more than 120 cm.

[0079] like Figure 1 As shown, in the second arches located in the open structure 500, the outermost second arch is connected to the first arch and is perpendicular to the first arch.

[0080] In a possible implementation, positioning ties are provided around the support module 300, one end of the positioning ties is connected to the adjacent support module 300, and the other end of the positioning ties is anchored 0.5-1m into the tunnel surrounding rock; and a mortar layer is provided around each positioning ties;

[0081] A plurality of anchor rods are respectively arranged on both sides of the bottom of each support module 300, and the anchor rods are connected to the support module 300 to form a leg locking device; a plurality of reinforcing ribs are arranged in the horizontal direction of each support module 300, and each reinforcing rib is connected to the support module 300 and anchored into the surrounding rock of the tunnel;

[0082] A reinforcement column is provided at the gap between the joist and the support module 300 .

[0083] Based on the above design, in addition to the support module 300, other supporting structures are set in the tunnel, among which the positioning tie bars are used for positioning so that the arch frame can be accurately installed at the designed position. The anchor rods play a supporting and reinforcing role, and the reinforcing bars play a role in preventing damage and deformation. The two cooperate with each other to improve the structural stability and safety of the tunnel.

[0084] It is easy to understand that when the tunnel needs to be expanded outward to increase the cross-sectional size of the tunnel, the installed positioning bars, anchor rods, reinforcing bars, reinforcing columns and other structures, as well as the removable structures, should be dismantled in a timely manner, and temporary support should be applied after the expansion is completed. The above process should be repeated until the expansion is completed, so that the support structure cooperates with the construction progress and ensures construction safety.

[0085] Embodiment 2:

[0086] This embodiment introduces a construction method for the non-vertical cross-shaped branch tunnel structure of the tunnel based on the non-vertical cross-shaped branch tunnel structure of the tunnel. Figure 3 As shown, the construction method comprises the following steps:

[0087] S1 tunnel construction: section construction interval division; expansion and excavation of branch tunnel 201, excavation to main tunnel 100; construction of main tunnel 100; after the settlement of tunnel intersection 400 converges and stabilizes, construction of other branch tunnels 200.

[0088] Based on this, zoned construction is adopted to effectively reduce local stress concentration, ensure the stability of the tunnel surrounding rock and the safety of tunnel construction, and cooperate with the setting of support modules 300 and other supporting structures to effectively solve the problem of stability of the large-span surrounding rock of the main tunnel 100.

[0089] The main skeleton is formed, and then excavation and / or expansion are carried out according to subsequent construction requirements.

[0090] During the construction of the main tunnel 100, construction is carried out toward one end of the main tunnel 100 to expand the volume of the construction guide tunnel, and then the other end of the main tunnel 100 is turned to be excavated, thereby forming the skeleton of the main tunnel 100. According to the direction of the opening structure 500 of the expanded branch tunnel 201, the main tunnel 100 is first excavated toward the end with a larger space at the intersection 400 of the tunnel after excavation, and then excavated toward the other end.

[0091] In S1, when the branch tunnel 201 is expanded and excavated to the main tunnel 100, a tunnel with a staggered distance of not less than 8m is excavated to serve as the main tunnel 100 and the construction guide tunnel; before the construction of the tunnel intersection 400, the shrinking anchor support is applied. Among them, after the settlement of the tunnel intersection 400 converges and stabilizes, the excavation and support of the branch tunnel 202 is carried out, and the two-step method is adopted for excavation, and at least 1m is reserved for the lower step.

[0092] In S1, the construction of the open structure 500 includes the following steps:

[0093] S100 middle guide tunnel construction: dig the middle guide tunnel obliquely upward to the top of the middle guide tunnel; expand and dig the top of the middle guide tunnel to form it; expand and dig the middle guide tunnel downward to form it;

[0094] Construction of the rest of S200: from top to bottom, construct the lower step and bottom protective layer respectively;

[0095] S300 repeats S100 and S200 to complete the construction of the expansion section 501 and the chamfer 502 respectively.

[0096] Based on this, the middle guide tunnel is excavated according to the principle of first lower and then upper, first middle and then trimming. The rock mass in the lower part of the section is excavated first. When excavating the upper part, due to the deadweight of the rock mass, the rock mass can be excavated more easily, improving construction efficiency. The rock mass in the middle part is excavated first, and the excavation speed is appropriately reduced when approaching the excavation contour line to improve the accuracy of excavation and avoid excessive over-excavation.

[0097] In addition, during the construction of the open structure 500, the cycle footage is no more than 3m; during the excavation of the middle guide tunnel, the tunnel face is backfilled with slag in layers. Based on this, resources are recycled and costs are saved.

[0098] S2 support construction: During tunnel construction, steel mesh is processed into pieces outside the tunnel simultaneously; as the tunnel is excavated, steel mesh is laid and welded inside the tunnel; positioning reinforcement and anchor rods are constructed; the first arch frame and the second arch frame are installed along the positioning reinforcement.

[0099] Among them, one end of the positioning tie bar is fixedly connected to the arch frame, and the other end is anchored into the surrounding rock 0.5-1m and anchored with mortar.

[0100] For the joist, considering the firmness of the second arch footing position at the step guide tunnel from the branch hole 200 to the main hole 100, the joist adopts an I-beam structure and is welded to the top of the second arch. For the first and second arches around the joist, reinforcing columns are set in the gap between the joist and the arch, and the reinforcing columns are welded to the arch and sprayed with C25 concrete to fill it tightly.

[0101] After the first arch frame and the second arch frame are installed, spray concrete as soon as possible to completely cover the steel frame with concrete so that the steel frame and the spray concrete are subjected to the force together.

[0102] S3 arch pipe shed construction: construct guide steel pipes along the tunnel excavation contour line and form guide walls.

[0103] Optionally, the longitudinal length of the guide wall is 1.5-2.5m, the thickness is 0.7-0.9m, and C30 concrete is used. The guide wall is provided with 4 I20a I-beams with a spacing of 55-65cm, and the outer edge of the steel frame is provided with a guide steel pipe with an outer diameter of 125-130mm and a wall thickness of 4-6mm. The guide wall construction mainly includes the processes of guide wall excavation, steel frame and guide pipe installation, formwork support and formwork installation, concrete pouring and maintenance, etc., and the construction can be carried out according to the existing construction method.

[0104] S4 mesh spraying support construction and lining construction. Based on this, the construction can be carried out according to the existing construction method.

[0105] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A tunnel non-vertical cross construction branch tunnel structure, characterized in that: It comprises a main hole (100), a branch hole (200) and a supporting module (300); The main tunnel (100) is connected to the branch tunnel (200), the connection between the main tunnel (100) and the branch tunnel (200) forms a tunnel intersection (400), and there are at least two branch tunnels (200); Each branch hole (200) is arranged obliquely relative to the main hole (100), and the connection between each branch hole (200) and the main hole (100) is constructed as an open structure (500), and accordingly, the open structure (500), the tunnel intersection (400) and one of the branch holes (200) form a turning space for equipment to turn around; At least three groups of support modules (300) are provided, and each group of support modules (300) is respectively arranged in a main tunnel (100) or a branch tunnel (200). Accordingly, a joist is provided at the axis of the arch of the main tunnel (100), and the joist extends to the tunnel intersection (400) and connects each group of support modules (300).

2. The non-vertical cross-construction branch tunnel structure of claim 1 is characterized in that: There is an acute angle between the main hole (100) and the branch hole (200); In each branch hole (200), the opening-shaped structure (500) includes an outward expansion section (501) and a chamfer (502). Accordingly, the outward expansion section (501) and the chamfer (502) are respectively located on two sides of the branch hole (200), and the outward expansion section (501) is far away from the included angle, while the chamfer (502) is close to the included angle.

3. The non-vertical cross-construction branch tunnel structure of claim 2 is characterized in that: The branch tunnel (200) comprises an expanded branch tunnel (201), a diverted branch tunnel (202) and at least one additional branch tunnel (200); The expanded branch tunnel (201) has two ends, one of which is connected to the main tunnel (100), and the other end extends obliquely upward and is connected to the outside. Accordingly, at least two gentle slopes with a slope of 2.5%-3.5% and a plurality of anti-collision piers are provided in the expanded branch tunnel (201); The turning branch hole (202) and the additional branch hole (200) are both arranged underground, and correspondingly, a plurality of crash piers are respectively arranged at the opening structures (500) of the turning branch hole (202) and the additional branch hole (200).

4. The non-vertical cross-construction branch tunnel structure according to any one of claims 1 to 3, characterized in that: The support module (300) comprises a first arch frame arranged along the main hole (100) and a second arch frame arranged along the branch hole (200); The first arch frames are evenly distributed in the main hole (100), and the distance between two adjacent first arch frames is no more than 50 cm; The second arch frame is divided into at least two support groups and is respectively arranged in one of the branch holes (200); correspondingly, the support groups and the branch holes (200) are arranged in a one-to-one correspondence; Each support group includes a plurality of second arch frames, wherein the second arch frames located in the body of the branch hole (200) are arranged at equal intervals, and the second arch frames located in the open structure (500) are arranged at intervals, and one end of each arch frame is connected to the chamfer (502) and the other end is connected to the expansion section (501).

5. The non-vertical cross-construction branch tunnel structure of claim 4 is characterized in that: The distance between two adjacent second arches located in the open structure (500) connected to one end of the chamfer (502) is no greater than 50 cm, and the distance between two adjacent second arches connected to one end of the expansion section (501) is no greater than 120 cm; Among the second arch frames located in the open structure (500), the second arch frame located at the outermost side is connected to the first arch frame and is perpendicular to the first arch frame.

6. The non-vertical cross-construction branch tunnel structure of claim 4 is characterized in that: Positioning reinforcement bars are arranged around the support modules (300), one end of the positioning reinforcement bars is connected to the adjacent support modules (300), and the other end of the positioning reinforcement bars is anchored into the tunnel surrounding rock by 0.5-1m; and a mortar layer is arranged around each positioning reinforcement bar; A plurality of anchor rods are respectively arranged on both sides of the bottom of each support module (300), the anchor rods are connected to the support module (300) and form a leg locking device; a plurality of reinforcing ribs are arranged in the horizontal direction of each support module (300), each reinforcing rib is connected to the support module (300) and anchored into the surrounding rock of the tunnel; A reinforcement column is provided at the gap between the support beam and the supporting module (300).

7. A construction method for a tunnel non-vertical cross construction branch tunnel structure according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1 tunnel construction: cross-section construction interval division; expansion and excavation of branch tunnels (201) to the main tunnel (100); construction of the main tunnel (100); after the settlement of the tunnel intersection (400) converges and stabilizes, the remaining branch tunnels (200) are constructed; S2 support construction: During tunnel construction, steel mesh is processed into pieces outside the tunnel; as the tunnel is excavated, steel mesh is laid and welded inside the tunnel; positioning tie bars and anchor rods are constructed; the first arch frame and the second arch frame are installed along the positioning tie bars; S3 arch pipe shed construction: construct guide steel pipes along the tunnel excavation contour and form guide walls; S4 mesh spraying support construction and lining construction.

8. The construction method of the tunnel non-vertical cross construction branch tunnel structure according to claim 7 is characterized in that: In S1, when the branch tunnel (201) is expanded and excavated to the main tunnel (100), a tunnel with a staggered distance of not less than 8m is excavated to serve as the main tunnel (100) and the construction guide tunnel; before the construction of the tunnel intersection (400), a shrink anchor support is applied.

9. The construction method of the tunnel non-vertical cross construction branch tunnel structure according to claim 8, characterized in that: In S1, the construction of the open structure (500) includes the following steps: S100 middle guide tunnel construction: dig the middle guide tunnel obliquely upward to the top of the middle guide tunnel; expand and dig the top of the middle guide tunnel to form it; expand and dig the middle guide tunnel downward to form it; Construction of the rest of S200: from top to bottom, construct the lower step and bottom protective layer respectively; S300 repeats S100 and S200 to complete the construction of the expansion section (501) and the chamfer (502) respectively.

10. The construction method of the tunnel non-vertical cross construction branch tunnel structure according to claim 9, characterized in that: During the construction of the open structure (500), the cycle advance is not more than 3m; during the excavation of the middle guide tunnel, the tunnel face is backfilled with slag in layers.

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