Reinforcing mesh fixing structure for tunnel shotcrete-anchor support and tunnel shotcrete-anchor support thereof

Abstract

The utility model relates to the technical field of foundation engineering equipment, and particularly discloses a reinforcing mesh fixing structure for a tunnel shotcrete-anchor support and the tunnel shotcrete-anchor support. The reinforcing mesh fixing structure is used for fixedly connecting a reinforcing mesh with an anchor body and mainly comprises a base plate set and a mounting part, the base plate set comprises a limiting base plate and a fixing base plate, and a limiting channel is formed in the limiting base plate and used for containing and fixing reinforcing steel bars in the reinforcing mesh; and a fixed surface is arranged on the fixed base plate, and when the base plate group is formed, the fixed surface covers the limiting channel. The mounting part comprises a combined mounting part and a fixed mounting part, the combined mounting part is used for promoting the limiting base plate and the fixed base plate to form a base plate group, and the fixed mounting part is used for fixing the position relation between the base plate group and the anchor body. The anchor rod has the advantages that according to actual working requirements, steel bars can be placed in any limiting channel to achieve connection between the steel bar mesh and the anchor rod, and the arrangement design of the steel bar mesh is more flexible.

Description

Technical Field

[0001] The utility model relates to the technical field of basic engineering equipment, and particularly relates to a fixing structure for a steel mesh used in tunnel shotcrete support and the tunnel shotcrete support. Background Technique

[0002] During the tunnel excavation process, the newly formed cavity will destroy the original balance state of the rock mass, resulting in the redistribution of surrounding rock stress, and finally causing the deformation, damage and collapse of the cavity. Therefore, during the tunnel excavation, shotcrete support needs to be erected in the tunnel to effectively control the deformation of the surrounding rock in a timely manner, prevent collapse, and ensure the safety and stability of tunnel construction. Usually, the shotcrete support is composed of materials such as anchor bolts, steel meshes, and shotcrete.

[0003] During processing, first, it is necessary to drill anchor bolt holes perpendicular to the rock surface or the surface of the initial shotcrete to ensure that the stress direction of the anchor bolt is consistent with the deformation direction of the surrounding rock. Then, the anchoring section of the anchor bolt is driven into the soil layer with high mechanical strength (such as sand layer, pebble layer and rock layer) to enhance the anchoring force. Subsequently, the steel mesh is fixed on the anchor bolt, and finally, concrete is sprayed to tightly fill the surface of the surrounding rock to form an initial shotcrete layer. The initial shotcrete layer is closely combined with the anchor bolt and the steel mesh to form a tunnel composite support. During this period, the step of fixing the steel mesh on the anchor bolt can not only prevent the steel mesh from moving during the spraying of concrete, but also enable the point support force provided by the anchor bolt and the surface support force provided by the steel mesh and the sprayed layer to form a synergistic effect, and can exert a better support effect.

[0004] In the prior art, the fixing methods of the anchor bolt and the steel mesh mainly include welding and directly pressing with an anchor bolt backing plate. However, the welding connection method highly depends on the technical level of on-site construction personnel, and it is inconvenient to check the connection quality. Moreover, in this method, it is necessary to ensure a certain distance between the steel bars in the steel mesh and the anchor bolt to achieve welding. In the actual operation process, the overall layout design requirements for the steel mesh are extremely high; while in the method of directly pressing with an anchor bolt backing plate, due to the overall flatness of the anchor bolt backing plate, when it is directly pressed on the steel mesh, the backing plate cannot fully contact with the formed initial shotcrete layer, which results in the backing plate being difficult to play the role of stress transfer. Content of the Utility Model

[0005] The technical problem to be solved by the utility model is to provide a fixing structure for a steel mesh used in tunnel shotcrete support, which can relax the spacing requirements between the anchor bolt and the steel bars in the steel mesh connected thereto, be adapted to more steel mesh layout situations, and at the same time, under the structure of the utility model, the contact area between the backing plate and the initial shotcrete layer is relatively large, optimizing the stress condition of the backing plate.

[0006] The utility model is realized through the following technical solutions:

[0007] A fixing structure for a steel mesh in tunnel shotcrete support is used to fixedly connect the steel mesh and the anchor body arranged on the inner wall of the tunnel. It includes: a backing plate group, which is provided with fixing holes allowing the anchor body to pass through, and is used to limit the positional relationship between the backing plate group and the anchor body; the backing plate group includes a limiting backing plate and a fixing backing plate. A number of limiting channels are arranged on the limiting backing plate, and the size of the limiting channels is adapted to the size of the steel bars in the steel mesh, and the arrangement position of the limiting channels is adapted to the arrangement position of the steel bars; a fixing surface is arranged around the fixing hole on the fixing backing plate. When forming the backing plate group, the fixing surface covers the limiting channels; an installation part, which includes a combined installation part and a fixing installation part. The combined installation part is arranged at the edge of the backing plate group and is used to facilitate the formation of the backing plate group by the limiting backing plate and the fixing backing plate; the fixing installation part is arranged on the external section of the anchor body and abuts against the backing plate group to fix the positional relationship between the backing plate group and the anchor body.

[0008] As a further improvement of the present invention, the combined installation part includes a number of sets of combined installation components. The combined installation component includes a first installation part arranged on the limiting backing plate, a second installation part arranged on the fixing backing plate, and an assembly part connecting the first installation part and the second installation part. An accommodation gap is formed between the first installation part and the second installation part, and the size of the accommodation gap is adapted to the size of the steel bar.

[0009] As a further improvement of the present invention, the assembly part includes a bolt arranged on the first installation part, a connection through hole and a first nut arranged on the second installation part. When the backing plate group is installed, an exposed section is formed after the bolt passes through the connection through hole, and the first nut is screwed onto the exposed section.

[0010] As a further improvement of the present invention, at least two bolts are included on the first installation part, and the number of bolts divides the accommodation gap. A first accommodation space is formed between two adjacent bolts, and the size of the first accommodation space is adapted to the size of the steel bar.

[0011] As a further improvement of the present invention, a second accommodation space is formed between the bolt on the first installation part close to the limiting backing plate and the limiting backing plate, and the size of the second accommodation space is adapted to the size of the steel bar.

[0012] As a further improvement of the present invention, the backing plate group is of a rectangular structure, and the combined installation part includes four sets of combined installation components, and the combined installation components are arranged at the four corners of the backing plate group.

[0013] As a further improvement of the present utility model, the combined mounting member is symmetric about the center of the backing plate group.

[0014] As a further improvement of the present utility model, the fixing holes are opened at the center of the backing plate group.

[0015] As a further improvement of the present utility model, the fixed mounting portion includes a second nut sleeved on the external section.

[0016] In a second aspect, the present utility model provides a tunnel shotcrete support, which uses any one of the above-mentioned steel mesh fixing structures for tunnel shotcrete support to complete the connection between the steel mesh and the anchor body.

[0017] The beneficial effects of the present utility model include:

[0018] (1) The fixing holes in the backing plate group are used to limit the positional relationship between the backing plate group and the anchor body, and the several limiting channels arranged in the limiting backing plate can limit the positional relationship between the steel bars in the steel mesh and the backing plate group. Therefore, according to actual working needs, any limiting channel in the limiting backing plate can be selected to place the steel bars, and the connection between the steel mesh and the closest anchor bolt can be realized. It is no longer required that the steel bars must be closely attached to the anchor bolt during the connection process, which makes the layout design of the steel mesh more flexible;

[0019] (2) The present backing plate group is composed of two backing plates clamped together, and the limiting backing plate is attached to the free face of the inner wall. Therefore, during the formation of the initial shotcrete layer, the limiting backing plate can be in full contact with the initial shotcrete layer, solving the problem of difficult stress transmission caused by the non-close contact between the backing plate and the initial shotcrete layer in the traditional connection method;

[0020] (3) The combined mounting member adopted in the present utility model can be regarded as an extension of the backing plate group. Therefore, for example, in the limiting backing plate, the first mounting member, as an extension of the limiting backing plate, can increase the contact area between the limiting backing plate and the initial shotcrete layer, further improving the stress transmission ability of the backing plate group; at the same time, the first accommodation space, the second accommodation space, etc. are formed in the combined mounting member extending from the backing plate group, which can further limit and fix the position of the steel bars, ensuring the accuracy and firmness of the fixed position between the steel mesh and the anchor bolt. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The following drawings are provided for combination with the preferred embodiments in the present utility model to help understand the purpose and advantages of the present utility model, wherein:

[0022] Figure 1 It is a top view after the installation of the steel mesh fixing structure;

[0023] Figure 2 It is a top view of the backing plate group;

[0024] Figure 3 Front view of the limit backing plate

[0025] Figure 4 Front view of the fixed backing plate

[0026] Figure 5 Schematic diagram of the placement of the first type of steel bars

[0027] Figure 6 Schematic diagram of the placement of the second type of steel bars

[0028] Figure 7 Schematic diagram of the placement of the third type of steel bars

[0029] Figure 8 Schematic diagram of the steel bar mesh structure Specific implementation mode

[0030] The following further elaborates on the present utility model based on the attached drawings and embodiments.

[0031] In this specification, orientation terms such as up, down, left, right, front, back, front side, back side, top, bottom, etc., which are mentioned or may be mentioned, are defined relative to the structures shown in the respective drawings. The terms "inner" and "outer" respectively refer to the directions towards or away from the geometric center of a specific component. They are relative concepts and may therefore change accordingly depending on their different positions and usage states. Therefore, these or other orientation terms should not be construed as restrictive terms.

[0032] Embodiment 1:

[0033] In this embodiment, a steel bar mesh fixing structure for tunnel shotcrete support is provided, which is used to fixedly connect the steel bar mesh B and the anchor A provided on the inner wall of the tunnel. The steel bar mesh fixing structure mainly includes a backing plate group 1 and a mounting portion 2.

[0034] The backing plate group 1 includes a limit backing plate 101 and a fixed backing plate 102. As shown in, a fixing hole 1-1 is provided on the backing plate group 1, that is, the limit backing plate 101 and the fixed backing plate 102 are both provided with the fixing hole 1-1 and are interconnected. When the steel bar mesh fixing structure is installed, as shown in, the fixing hole 1-1 can accommodate the anchor rod A to pass through, and a section of the anchor rod A outside the backing plate group 1 is the external section A-1. Figures 1 - 4 shown, the fixing hole 1-1 can accommodate the anchor rod A to pass through, and a section of the anchor rod A outside the backing plate group 1 is the external section A-1. Figure 1 shown, the fixing hole 1-1 can accommodate the anchor rod A to pass through, and a section of the anchor rod A outside the backing plate group 1 is the external section A-1.

[0035] In this embodiment, the structure of the limit backing plate 101 is as shown in Figures 2 - 3As shown, there are eight transverse and eight vertical limiting channels 101-1 arranged around the fixing hole 1-1, and the limiting channels 101-1 of the same transverse or vertical direction are parallel to each other, and the connection parts between the transverse limiting channels 101-1 and the vertical limiting channels 101-1 are interconnected. In this embodiment, as Figure 8 shown, the steel bar mesh B is formed by connecting and combining a number of mutually perpendicular steel bars B-1. Therefore, the arrangement position of the limiting channels 101-1 in the limiting backing plate 101 is adapted to the structure of the steel bar mesh B. At the same time, the width of the limiting channel 101-1 is consistent with the diameter of the steel bar B-1, so that the steel bar B-1 can just be placed in it; and in the structure of the steel bar mesh B, as Figure 1 shown, the structure between two mutually perpendicular steel bars B-1 is an overlapping connection structure. Therefore, the depth of the limiting channel 101-1 is twice the diameter of the steel bar B-1, and overall, the size of the limiting channel 101-1 is adapted to the size of the steel bar mesh B. The above arrangement structure of the limiting channel 101-1 ensures that the installation position of the steel bar mesh B can be as Figure 5 shown, that is, the steel bar B-1 can be connected to the anchor rod A without being in close contact with the anchor rod A passing through the fixing hole 1-1, ensuring the mutual transfer of stress between the two.

[0036] In this embodiment, the structure of the fixing backing plate 102 is as Figure 2 、 4 shown, and a complete fixing surface is arranged around the fixing hole 1-1. Therefore, when the steel bar mesh fixing structure is installed, as Figures 1 - 2 shown, the fixing surface covers all the limiting channels 101-1 on the limiting backing plate 101, ensuring that the steel bar B-1 will not come out of the limiting channel 101-1.

[0037] In this embodiment, the installation part 2 mainly includes two parts, namely the combined installation part 201 and the fixed installation part 202. The combined installation part 201 ensures that the limiting backing plate 101 and the fixing backing plate 102 are closely attached to form a complete backing plate group 1, and the fixed installation part 202 is as Figure 1 shown, and is used to drive the backing plate group 1 close to the primary sprayed layer C to ensure that the backing plate group 1 is closely connected to the anchor rod A, actually ensuring the fixation of the relative position between the steel bar mesh B installed on the backing plate group 1 and the anchor rod A.

[0038] Preferably, the combined installation part 201 includes combined installation parts 201-1 arranged on the edge part of the backing plate group 1. In this embodiment, the combined installation parts 201-1 are further preferably four sets. As Figures 2 - 4As shown, the combined mounting member 201-1 includes a first mounting member 201-1-1 disposed on the limit backing plate 101, a second mounting member 201-1-2 disposed on the fixed backing plate 102, and an assembly member 201-1-3 for connecting the first mounting member 201-1-1 and the second mounting member 201-1-2. A receiving gap is formed between the first mounting member 201-1-1 and the second mounting member 201-1-2.

[0039] In this embodiment, the depth of the receiving gap is the same as the diameter of the steel bar B-1. Therefore, the steel bar B-1 can pass through the receiving gap. On the other hand, it means that the first mounting member 201-1-1 and the second mounting member 201-1-2 clamp the steel bar B-1 placed in the receiving gap. In fact, the combined mounting member 201-1 produces an additional fixing effect on the steel bar B-1, further strengthening the fixation of the relative position between the steel bar mesh B and the anchor rod A.

[0040] The combined mounting member 201-1 is disposed at the edge of the backing plate group 1. On the one hand, it avoids interfering with the limit channel 101-1 in the backing plate group 1; on the other hand, the first mounting member 201-1-1 can serve as an extension of the limit backing plate 101, increasing the contact area between the limit backing plate 101 and the primary shotcrete layer C, and further ensuring the normal stress transfer of the backing plate group 1.

[0041] Preferably, in this embodiment, the assembly member 201-1-3 includes a bolt 201-1-3a disposed on the first mounting member 201-1-1, a connection through hole 201-1-3b disposed on the second mounting member 201-1-2, and a first nut 201-1-3c. When installing the backing plate group 1, the bolt 201-1-3a on the first mounting member 201-1-1 passes through the connection through hole 201-1-3b on the second mounting member 201-1-2 to form an exposed section exposed outside the assembly member 201-1-3. The first nut 201-1-3c is sleeved on the exposed section and tightened, so that the first nut 201-1-3c abuts against the second mounting member 201-1-2, thereby driving the limit backing plate 101 and the fixed backing plate 102 to fit together to form the backing plate group 1.

[0042] Preferably, in this embodiment, as Figures 2 - 4As shown, the first mounting member 201-1-1 is provided with two bolts 201-1-3a, while the second mounting member 201-1-2 is provided with two matching connecting through holes 201-1-3b. In this structure, the two bolts 201-1-3a are separated by the width of the accommodation gap, forming a first accommodation space a1 between two adjacent bolts 201-1-3a. The depth of the first accommodation space a1 is the depth of the accommodation gap, while the width is determined by the distance between the two bolts 201-1-3a. In this embodiment, the width is consistent with the diameter of the steel bar B-1, which makes it possible to Figure 6 As shown, the steel bar B-1 can be fixed between the two bolts 201-1-3a, further increasing the fixing points of the steel bar B-1, ensuring the firmness of the connection between the steel mesh B and the anchor rod A and the accuracy of the connection position.

[0043] Further preferably, a second accommodation space a2 is formed between the bolt 201-1-3a closest to the limiting pad 101 on the first mounting member 201-1-1 and the limiting pad 101. The depth of the second accommodation space a2 is also the depth of the accommodation gap, and the width is determined by the distance between the bolt 201-1-3a and the limiting pad 101. In this embodiment, the width is consistent with the diameter of the steel bar B-1, which makes it possible to Figure 7 As shown, the steel bar B-1 can be fixed between the bolt 201-1-3a and the limiting pad 101, further increasing the fixing points of the steel bar B-1, ensuring the firmness of the connection between the steel mesh B and the anchor rod A and the accuracy of the connection position.

[0044] Preferably, if Figures 2 - 4 As shown, the limiting pad 101 and the fixed pad 102 are both rectangular structures, that is, the pad group 1 formed by the combination is also a rectangular structure, and the four sets of combined mounting parts 201-1 in this embodiment are respectively arranged at the four corners of the pad group 1. Under this structure, it can ensure that the limiting pad 101 and the fixed pad 102 are tightly fitted on all sides, and the combined pad group 1 fixes the steel bar B-1 more firmly. At the same time, it is further preferred that the four sets of combined mounting parts 201-1 are symmetrical about the center of the pad group 1. The centrally symmetrical arrangement makes the connection combination of the combined mounting parts 201-1 more secure.

[0045] Preferably, if Figure 3 、 4 As shown, the fixing hole 1-1 is opened at the center of the pad group 1. The layout of the limit channel 101-1 on the lower limit pad of this structure will be evenly arranged around the position of the anchor rod A. The placement of the steel bar B-1 can be carried out with the anchor rod A as the center as much as possible to ensure the uniform transfer of stress as much as possible.

[0046] Preferably, in this embodiment, Figure 1As shown, the fixed installation part 202 includes a second nut 202-1 sleeved on the external section A-1. When the overall installation of the steel mesh fixing structure is completed, the second nut 202-1 abuts against the backing plate group 1 and drives it to move along the axial direction of the bolt A to fit against the primary shotcrete layer C, thereby ensuring the fixed connection between the backing plate group 1 and the bolt A, and at the same time ensuring the complete and tight fit between the limiting backing plate 101 and the primary shotcrete layer C.

[0047] Embodiment 2:

[0048] To assist in understanding the composition of the steel mesh fixing structure, this embodiment provides an installation method for the steel mesh fixing structure in Embodiment 1.

[0049] During the tunnel processing, a free face is formed on the surface of the rock and soil mass in the tunnel, and shotcrete is sprayed on the free face to form the primary shotcrete layer C as shown. Then, drilling construction of the bolt A is carried out on the rock and soil mass and the bolt A is placed. After the bolt A is placed in place, grouting is carried out in the drill hole to complete the fixing work of the bolt A. Figure 1 Subsequently, the installation work of the backing plate group 1 is carried out. Specifically, first, the limiting backing plate 101 is sleeved on the bolt A through the fixing hole 1-1 thereon, and at the same time, the whole limiting backing plate 101 is driven to be in close contact with the primary shotcrete layer C. Subsequently, the steel mesh B is fabricated on site and laid. In this embodiment, taking

[0050] as an example, the steel bar B-1 in the steel mesh B is embedded in the corresponding limiting channel 101-1 or the combined installation part 201-1 to complete the preliminary fixing work of the steel mesh B. Then, the fixing backing plate 102 is sleeved on the bolt A through the fixing hole 1-1, and at the same time, the fixing backing plate 102 and the limiting backing plate 101 are driven to fit together so that the fixing surface can cover all the limiting channels 101-1. During this period, the combined installation part 201-1 is used to complete the connection and fixing work around the limiting backing plate 101 and the fixing backing plate 102, and the second nut 202-1 is used to complete the fitting and combination work at the center of the backing plate group 1. At the same time, the fixing between the backing plate group 1 and the bolt A is realized. Figure 6 Finally, shotcrete is sprayed again on the steel mesh fixing structure to form a complete tunnel shotcrete support.

[0051] Embodiment 3:

[0052] This embodiment provides a tunnel shotcrete support, in which the connection work between the steel mesh B and the anchor body A is completed by using the steel mesh fixing structure for tunnel shotcrete support described in Embodiment 1.

[0053]

[0054] ​Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A fixing structure for a steel bar mesh in tunnel shotcrete support, which is used to fixedly connect the steel bar mesh (B) and the anchor body (A) arranged on the inner wall of the tunnel, and is characterized in that, It includes: A backing plate group (1) is provided with fixing holes (1-1) allowing the anchor body (A) to pass through, for restricting the positional relationship between the backing plate group (1) and the anchor body (A); the backing plate group (1) includes a limiting backing plate (101) and a fixing backing plate (102), several limiting channels (101-1) are arranged on the limiting backing plate (101), the size of the limiting channels (101-1) is adapted to the size of the steel bars (B-1) in the steel bar mesh (B), and the arrangement position of the limiting channels (101-1) is adapted to the arrangement position of the steel bars (B-1); a fixing surface is arranged around the fixing hole (1-1) on the fixing backing plate (102), and when forming the backing plate group (1), the fixing surface covers the limiting channels (101-1). An installation part (2) includes a combined installation part (201) and a fixing installation part (202), the combined installation part (201) is used to facilitate the formation of the backing plate group (1) by the limiting backing plate (101) and the fixing backing plate (102); the fixing installation part (202) is arranged on the external section (A-1) of the anchor body (A) and abuts against the backing plate group (1) to fix the positional relationship between the backing plate group (1) and the anchor body (A).

2. The steel bar mesh fixing structure for tunnel shotcrete support according to claim 1, characterized in that, The combined installation part (201) includes several combined installation pieces (201-1) sleeved on the edge part of the backing plate group (1), the combined installation piece (201-1) includes a first installation piece (201-1-1) arranged on the limiting backing plate (101), a second installation piece (201-1-2) arranged on the fixing backing plate (102), and an assembly piece (201-1-3) connecting the first installation piece (201-1-1) and the second installation piece (201-1-2), wherein an accommodation gap is formed between the first installation piece (201-1-1) and the second installation piece (201-1-2), and the size of the accommodation gap is adapted to the size of the steel bar (B-1).

3. A steel bar mesh fixing structure for tunnel shotcrete support according to claim 2, characterized in that, The assembly piece (201-1-3) includes a bolt (201-1-3a) arranged on the first installation piece (201-1-1), a connection through hole (201-1-3b) and a first nut (201-1-3c) arranged on the second installation piece (201-1-2). When the backing plate group (1) is installed, an exposed section is formed after the bolt (201-1-3a) passes through the connection through hole (201-1-3b), and the first nut (201-1-3c) is screwed on the exposed section.

4. A steel mesh fixing structure for tunnel shotcrete support according to claim 3, characterized in that, At least two bolts (201-1-3a) are included on the first installation piece (201-1-1), several bolts (201-1-3a) will divide the accommodation gap, and a first accommodation space (a1) is formed between two adjacent bolts (201-1-3a), and the size of the first accommodation space (a1) is adapted to the size of the steel bar (B-1).

5. A steel mesh fixing structure for tunnel shotcrete support according to claim 4, characterized in that, A second accommodation space (a2) is formed between the bolt (201-1-3a) on the first mounting member (201-1-1) close to the limit backing plate (101) and the limit backing plate (101), and the size of the second accommodation space (a2) is adapted to the size of the steel bar (B-1).

6. A steel bar mesh fixing structure for tunnel shotcrete support according to any one of claims 2 to 5, characterized in that, The backing plate group (1) is of a rectangular structure, the combined mounting part (201) includes four sets of combined mounting members (201-1), and the combined mounting members (201-1) are arranged at the four corners of the backing plate group (1).

7. A steel bar mesh fixing structure for tunnel shotcrete support according to claim 6, characterized in that, The combined mounting members (201-1) are symmetric about the center of the backing plate group (1).

8. A steel bar mesh fixing structure for tunnel shotcrete support according to claim 1, characterized in that, The fixing hole (1-1) is formed at the center of the backing plate group (1).

9. A steel mesh fixing structure for tunnel shotcrete support according to claim 1, characterized in that, The fixed mounting part (202) includes a second nut (202-1) sleeved on the external section (A-1).

10. A tunnel shotcrete and bolting support, characterized in that, The connection between the steel bar mesh (B) and the anchor body (A) is completed by using a steel bar mesh fixing structure for tunnel shotcrete support according to any one of claims 1 to 9.

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