Active supporting structure for tunnel face

Abstract

The utility model relates to the technical field of tunnel reinforcement, in particular to an active supporting structure for a tunnel face. The active supporting structure comprises a reinforcing mesh and a concentrator, the reinforcing mesh is connected with a tunnel face, the reinforcing mesh comprises main reinforcing steel bars and auxiliary reinforcing steel bars, the main reinforcing steel bars are arranged in a radial mode, the auxiliary reinforcing steel bars are annularly connected with the main reinforcing steel bars, and the main reinforcing steel bars are connected with the concentrator. According to the active supporting and reinforcing structure, the concentrator drives the main steel bars to tighten the steel bar net, the pre-tightening effect is achieved, the active pressure effect of the steel bar net on surrounding rock is conveniently achieved, self-healing of broken rock mass is achieved, and safety and stability of tunnel construction are guaranteed.

Description

TECHNICAL FIELD

[0001] The utility model relates to a tunnel reinforcement technical field, concretely relates to a tunnel face active support structure. BACKGROUND

[0002] In tunnel construction, the support measures after excavation are crucial to guarantee the temporary stability of the tunnel and subsequent construction. Due to the complex geological conditions and low strength of the rock-soil body, the face of the tunnel is prone to deformation under the action of longitudinal extrusion pressure, leading to instability of the surrounding rock and threatening the safety of construction. Therefore, the support and reinforcement of the face is the key to ensuring the stability of the tunnel. The current support and reinforcement methods include reserving core soil, changing the shape of the face, and spraying concrete, but these methods often need to be used in combination in large-span weak surrounding rock tunnels, which is complex, time-consuming, and material-consuming, and does not fully utilize the self-stabilizing capacity of the rock-soil body. Therefore, there is an urgent need to develop a more convenient and efficient face support structure. SUMMARY

[0003] The technical problem to be solved by the utility model is to provide a convenient and efficient tunnel face active support structure.

[0004] To solve the above technical problem, the utility model adopts the technical scheme of a tunnel face active support structure, which comprises a reinforcing mesh and a concentrator, the reinforcing mesh is connected with the tunnel face, the reinforcing mesh comprises main reinforcing bars and auxiliary reinforcing bars, the main reinforcing bars are arranged in a radial manner, the auxiliary reinforcing bars are arranged in a ring shape and connected with the main reinforcing bars, and the main reinforcing bars are connected with the concentrator.

[0005] The utility model further comprises a primary support anchor rod, and the main reinforcing bars are detachably connected with the primary support anchor rod and the concentrator in sequence.

[0006] The one end of the primary support anchor rod is embedded in the tunnel face, the other end is provided with a limiting piece, and the main reinforcing bars pass through the limiting piece.

[0007] The limiting piece is L-shaped.

[0008] The limiting piece is connected with the primary support anchor rod to form a hook-shaped structure, and the main reinforcing bars pass through the hook-shaped structure and are connected with the concentrator.

[0009] The one end of the primary support anchor rod provided with the limiting piece is provided with a fixing piece, and the main reinforcing bars pass through the limiting piece and the fixing piece in sequence.

[0010] The fixing piece comprises a bolt and a nut, the nut is connected with the limiting piece, the bolt is threadedly connected with the nut, and the main reinforcing bars pass through the bolt and the nut.

[0011] The fixing piece and the limiting piece are welded at the one end of the primary support anchor rod.

[0012] The initial support anchor rod is exposed from the tunnel face by 5-8 cm.

[0013] The steel mesh is in a spider web shape.

[0014] The tunnel face active support reinforcing structure has the advantages that: the main steel is driven by the hub to tighten the steel mesh, so that the pre-tightening effect is achieved; after the temporary support of the steel mesh is completely tightened, the hub is closed. The hub is used to ensure the tightness of the steel mesh, so that the active pressure of the steel mesh on the surrounding rock is conveniently realized, the fractured rock mass is re-compacted under the combined action of the vertical load and the active pressure, the self-healing of the fractured rock mass is realized, and the safety and stability of the tunnel construction are ensured. The reinforcing structure maximally utilizes the bearing capacity of the surrounding rock itself, can reduce the support operation of the face, and saves support materials. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 is a schematic view of the active support reinforcing structure of the utility model embodiment;

[0016] Figure 2 is a schematic view of the structure of the steel mesh of the utility model embodiment;

[0017] Figure 3 is a schematic view of the connection structure of the steel mesh and the limiting piece of the utility model embodiment;

[0018] Label explanation:

[0019] 1, tunnel; 2, tunnel face; 3, steel mesh; 4, initial support anchor rod; 5, limiting piece; 6, hub; 7, fixing piece; 8, main steel. DETAILED DESCRIPTION

[0020] To make the technical content, purposes and effects of the utility model clear, the following will be described in detail in combination with the embodiments and the drawings.

[0021] Please refer to Figure 1 and Figure 2 A tunnel face active support structure, comprising a steel mesh and a hub, the steel mesh is connected with the tunnel face, the steel mesh comprises main steel and auxiliary steel, the main steel is arranged in a radial shape, the auxiliary steel is arranged in a ring shape and connected with the main steel, and the main steel is connected with the hub.

[0022] From the above description, the utility model discloses a kind of self-healing characteristics of rupture surface after strain hardening of surrounding rock, summarizes a kind of tunnel face active support reinforcement structure suitable for complex geological conditions under the conditions of weak surrounding rock stratum, high degree of rock mass fragmentation.Specifically, the utility model sets up the steel mesh connected with tunnel face, then the main reinforcement of steel mesh is connected with concentrator, and the steel mesh is tightened when concentrator concentrates, and active support effect is exerted to tunnel face, and active support pressure is provided to tunnel face;It can effectively exert the self-healing characteristics of surrounding rock with strain hardening characteristics, maximize the bearing capacity of surrounding rock itself, reduce tunnel face supporting operation, and save support material;The active support structure has the advantages of simple structure, convenient operation and low cost, and the disturbance to tunnel surrounding rock is small, which is more conducive to the safety and stability of construction.

[0023] Further, it further includes primary support anchor rod, and the main reinforcement is detachably connected with the primary support anchor rod and the concentrator in sequence.

[0024] From the above description, the steel mesh is tightly set on tunnel face by primary support anchor rod.The main reinforcement is detachably connected with the primary support anchor rod and the concentrator in sequence, which facilitates temporary support.

[0025] Further, one end of the primary support anchor rod is embedded in the tunnel face, and the other end is provided with a limiting piece; the main reinforcement passes through the limiting piece to realize the connection between the steel mesh and the primary support anchor rod.

[0026] Please refer to Figure 3 Further, the limiting piece is L-shaped, and one end of the limiting piece is connected with one end of the primary support anchor rod.

[0027] Further, the limiting piece is connected with the primary support anchor rod to form a hook-shaped structure, and the main reinforcement passes through the hook-shaped structure and is connected with the concentrator.

[0028] From the above description, the main reinforcement passes through the limiting piece to realize the connection between the steel mesh and the primary support anchor rod, and the connection mode is easy to disassemble, which is beneficial to the reuse of support structure.

[0029] Further, one end of the primary support anchor rod is provided with a fixing piece, and the main reinforcement passes through the limiting piece and the fixing piece in sequence.

[0030] Further, the fixing piece includes a bolt and a nut, the nut is connected with the limiting piece, and the bolt is threadedly connected with the nut; the main reinforcement passes through the bolt and the nut.

[0031] From the above description, the main reinforcement passing through the limiting piece is wound between the nut and the bolt, and then the distance between the nut and the bolt is adjusted by rotating the bolt to clamp the main reinforcement, thereby reducing the tightening resistance of the concentrator.

[0032] Further, the fixing member and the limiting member are welded at one end of the primary support anchor rod.

[0033] Further, the primary support anchor rod is exposed 5-8 cm from the tunnel face.

[0034] From the above description, the primary support anchor rod is embedded in the tunnel face and exposed 5-8 cm to install the limiting member.

[0035] Further, the steel mesh is in the shape of a spider web.

[0036] From the above description, the steel mesh in the shape of a spider web has high bearing capacity and meets the support force calculated based on the wedge balance theory.

[0037] Referring to FIGS. 1-3, the embodiment one of the utility model is: a tunnel face active support structure, including primary support anchor rod 4, steel mesh 3, concentrator 6, limiting member 5 and fixing member 7. Steel mesh 3 is connected with tunnel face 2, and steel mesh 3 includes main reinforcement 8 and auxiliary reinforcement, main reinforcement 8 is arranged in the shape of a spider web, auxiliary reinforcement is in the shape of a ring and is connected with main reinforcement 8, and steel mesh 3 is in the shape of a spider web;Fixing member 7 includes bolt and nut, and bolt is threadedly connected with nut;One end of primary support anchor rod 4 is embedded in tunnel face 2, and the other end is exposed 6 cm from tunnel face 2 and is welded with the nut of fixing member 7 and one end of L-shaped limiting member 5, L-shaped limiting member 5 is connected with primary support anchor rod 4 to form a hook-shaped structure, and main reinforcement 8 is sequentially threaded through the hook-shaped structure and bolt and nut and is connected with concentrator 6.

[0038] The principle of the utility model is: embedding primary support anchor rod 4 on the tunnel face 2 of the excavated tunnel 1, welding the exposed end of primary support anchor rod 4 with the nut and one end of L-shaped limiting member 5, lifting steel mesh 3 and erecting it at tunnel face 2, and then limiting main reinforcement 8 by threading it through limiting member 5 and bolt and nut through manual operation, and then connecting it with concentrator 6;Pulling main reinforcement 8 through concentrator 6 and tightening steel mesh 3 to complete tensioning. After the surrounding rock is in a self-stable state, steel mesh 3 is removed, and the next cycle of excavation operation is carried out.

[0039] In summary, the tunnel face active support structure provided by the utility model has the following advantages:

[0040] 1. Pulling main reinforcement through a concentrator to tighten steel mesh to provide active support pressure for the tunnel face, which is simple in structure and convenient to operate.

[0041] 2. Connecting main reinforcement and primary support anchor rod through L-shaped limiting member, which is easy to disassemble and facilitates temporary support.

[0042] 3. Clamping main reinforcement through a fixing member to reduce the tightening resistance of the concentrator.

[0043] The above merely describes the embodiments of the present application, and does not limit the patent scope of the present application, and any equivalent transformation or direct or indirect application in the related technical field based on the content of the present application specification and drawings is also included in the patent protection scope of the present application.

Claims

1. A tunnel face active support structure, characterized by, The application relates to a tunnel face connecting reinforcing mesh and a hub, wherein the reinforcing mesh is connected with a tunnel face, and the reinforcing mesh comprises main reinforcing bars and auxiliary reinforcing bars; the main reinforcing bars are arranged radially; the auxiliary reinforcing bars are arranged in a ring shape and are connected with the main reinforcing bars; and the main reinforcing bars are connected with the hub.

2. A tunnel face active support structure according to claim 1, characterised in that, The main reinforcing bars are detachably connected with a primary support anchor rod and the hub in sequence.

3. A tunnel face active support structure according to claim 2, characterised in that, One end of the primary support anchor rod is embedded in the tunnel face, and the other end is provided with a limiting piece; and the main reinforcing bars pass through the limiting piece.

4. A tunnel face active support structure according to claim 3, characterised in that, The limiting piece is in an L shape.

5. A tunnel face active support structure according to claim 4, characterised in that, The limiting piece is connected with the primary support anchor rod to form a hook structure, and the main reinforcing bars pass through the hook structure and are connected with the hub.

6. A tunnel face active support structure according to claim 3, characterised in that, One end of the primary support anchor rod provided with the limiting piece is provided with a fixing piece, and the main reinforcing bars pass through the limiting piece and the fixing piece in sequence.

7. A tunnel face active support structure according to claim 6, characterised in that, The fixing piece comprises a bolt and a nut, the nut is connected with the limiting piece, the bolt is threadedly connected with the nut, and the main reinforcing bars pass through the bolt and the nut.

8. A tunnel face active support structure according to claim 6, characterised in that, The fixing piece and the limiting piece are welded at one end of the primary support anchor rod.

9. A tunnel face active support structure according to claim 3, characterised in that, The primary support anchor rod is exposed from the tunnel face by 5-8 cm.

10. The tunnel face active support structure according to claim 1, characterized in that, The reinforcing mesh is in a spider web shape.

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