Electromagnetic shielding concrete slab with built-in conductive network

Abstract

The utility model relates to civil engineering and electromagnetic protection technical field, concretely disclose a kind of electromagnetic shielding concrete slab of built-in conductive network, including substrate body, substrate body inside is provided with end hook type main steel fiber, adopt end hook type main steel fiber to build three-dimensional conductive network in advance in mould, directional or random space framework is formed, microsection auxiliary steel fiber is embedded at the gap between end hook type main steel fiber, two sides of end hook type main steel fiber construct framework positioning rib, framework positioning rib is horizontally and vertically grid-like distribution, is inserted between end hook type main steel fiber, pours high fluidity cement-based paste into three-dimensional conductive network, to this can stabilize fiber distribution position, improve the connectivity of conductive path, effectively avoid secondary radiation interference, and by high fluidity paste infiltration process cooperate pre-constructed framework, large size plate body one-time forming can be realized.

Description

Technical Field

[0001] This utility model relates to the fields of civil engineering and electromagnetic protection technology, and in particular to an electromagnetic shielding concrete plate with a built-in conductive network. Background Technology

[0002] Current research on concrete shielding materials mainly focuses on: adding metal powders and carbon-based materials (such as graphite, carbon fiber, and carbon black) to improve conductivity; and using steel mesh or metal mesh as an additional shielding layer. Most existing electromagnetic shielding concretes have the following problems: discontinuous conductive paths, random fiber distribution and severe agglomeration, resulting in unstable shielding; reflection-dominant rather than absorption-dominant, leading to secondary radiation problems; complex construction and difficult molding, making it impossible to achieve a uniform conductive network in large-size structures. Utility Model Content

[0003] The purpose of this invention is to provide an electromagnetic shielding concrete slab with a built-in conductive network, which aims to solve the technical problems in the prior art, such as discontinuous conductive paths, random fiber distribution and severe agglomeration, resulting in unstable shielding; reflection-dominant rather than absorption-dominant, leading to secondary radiation problems; complex construction and difficult molding, making it impossible to achieve a uniform conductive network in large-size structures.

[0004] To achieve the above objectives, this utility model employs an electromagnetic shielding concrete slab with a built-in conductive network, comprising a substrate body, wherein hook-shaped main steel fibers are provided inside the substrate body, and a three-dimensional conductive network is pre-built in a mold using the hook-shaped main steel fibers to form an oriented or random spatial skeleton, and micro-segment auxiliary steel fibers are embedded in the gaps between the hook-shaped main steel fibers. Skeleton positioning ribs are constructed on both sides of the hook-shaped main steel fiber. The skeleton positioning ribs are distributed in a horizontal and vertical grid pattern and are interspersed between the hook-shaped main steel fibers. High-flowability cement-based slurry is poured into the three-dimensional conductive network.

[0005] Among them, the skeleton positioning ribs are provided with skeleton fixing buckles.

[0006] The high-flowability cement-based slurry contains fine aggregates of quartz sand.

[0007] The outer surfaces of the hook-shaped main steel fiber and the micro-segment auxiliary steel fiber are coated with a fiber coupling agent layer.

[0008] The outer surface of the fiber coupling agent layer is coated with a fiber anti-rust layer.

[0009] A layered conductive interface transition layer is cast between the upper and lower surfaces of the substrate body and the three-dimensional conductive network.

[0010] The layered conductive interface transition layer has embedded reinforcing meshes attached to its upper and lower outer surfaces, and the embedded reinforcing meshes are completely embedded in the high-flowability cement-based slurry.

[0011] The substrate body has a surface anti-crack fiber mesh on its upper and lower outer surfaces.

[0012] Compared with the prior art, this utility model has the following advantages: 1. The three-dimensional structure of the main steel fiber skeleton with the micro-segment auxiliary steel fiber filling effectively improves the connectivity of the conductive network, and the shielding effectiveness in the 3-13GHz frequency band is stably 40-45dB, solving the problem of conductive path breakage.

[0013] 2. The layered conductive interface transition layer optimizes wave impedance matching, allowing electromagnetic waves to undergo a process of reflection, absorption, multiple scattering, and heat dissipation within the board, thus avoiding secondary radiation interference caused by traditional reflection-dominated processes.

[0014] 3. The hook-shaped main steel fiber and the telescopic embedded reinforcing mesh work together to make the compressive strength of the substrate body ≥200MPa and the bending toughness ≥30kJ / m², and the shielding effectiveness is improved by about 3 orders of magnitude compared with ordinary concrete, realizing the integration of structural load-bearing and shielding protection.

[0015] 4. The high-flowability slurry infiltration process, combined with the pre-structured skeleton, enables large-size panels to be formed in one go, eliminating the need for subsequent metal mesh laying or coating construction, effectively improving construction efficiency and reducing project costs. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a structural schematic diagram of an electromagnetic shielding concrete plate with a built-in conductive network according to this utility model.

[0018] Figure 2 This is a front view of an electromagnetic shielding concrete slab with a built-in conductive network according to this utility model.

[0019] Figure 3 This is the utility model Figure 2 A cross-sectional view of the AA line structure.

[0020] Figure 4 This is the utility model Figure 3 Magnification of the local structure at point B Figure 1 .

[0021] Figure 5 This is the utility model Figure 3 Magnification of the local structure at point B Figure 2 .

[0022] 101-Substrate body, 102-Hook-shaped main steel fiber, 103-Micro-segment auxiliary steel fiber, 104-Frame positioning rib, 105-Frame fixing buckle, 106-High fluidity cement-based slurry, 107-Quartz sand fine aggregate, 108-Fiber coupling agent layer, 109-Fiber anti-rust layer, 110-Layered conductive interface transition layer, 111-Embedded reinforcing mesh, 112-Surface crack-resistant fiber mesh. Detailed Implementation

[0023] The embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, but should not be construed as limiting the present invention.

[0024] Please see Figures 1-5 ,in Figure 1 This is a structural schematic diagram of an electromagnetically shielded concrete plate with a built-in conductive network according to this utility model. Figure 2 This is a front view of an electromagnetically shielded concrete slab with a built-in conductive network according to this utility model. Figure 3 This is the utility model Figure 2 AA-line structural cross-sectional view, Figure 4 This is the utility model Figure 3 Magnification of the local structure at point B Figure 1 , Figure 5 This is the utility model Figure 3 Magnification of the local structure at point B Figure 2 .

[0025] In this embodiment, the substrate body 101 is internally provided with hook-shaped main steel fibers 102. A three-dimensional conductive network is pre-built within the mold using the hook-shaped main steel fibers 102, forming a directional or randomized spatial skeleton. Micro-segment auxiliary steel fibers 103 are embedded in the gaps between the hook-shaped main steel fibers 102. Skeleton positioning ribs 104 are constructed on both sides of the hook-shaped main steel fibers 102, and these ribs are distributed in a horizontal and vertical grid pattern, interspersed between the hook-shaped main steel fibers 102. High-flowability cement-based slurry 106 is poured into the three-dimensional conductive network. The substrate body 101 serves as the core carrier for the overall structure's load-bearing and shielding functions. The core area inside the substrate body 101 is provided with... The hook-shaped main steel fiber 102 is pre-built into a directional or random three-dimensional conductive network in a special mold at a dosage of 7-8 vol% to form a spatial skeleton. The micro-segment auxiliary steel fiber 103 at a dosage of 1 vol% is embedded in the gaps between the hook-shaped main steel fibers 102 to fill the gaps in the skeleton and ensure conductive continuity. The skeleton positioning ribs 104 are laid on both sides of the three-dimensional conductive network formed by the hook-shaped main steel fiber 102 along the horizontal and vertical directions. The skeleton positioning ribs 104 are used to lock the position of the hook-shaped main steel fiber 102 to prevent displacement during seepage. The high-flowability cement-based slurry 106 is seeped into the three-dimensional conductive network layer by layer to ensure that all gaps in the three-dimensional network are filled.

[0026] Among them, a skeleton fixing buckle 105 is provided between the skeleton positioning ribs 104, and the skeleton fixing buckle 105 is used to lock and fix the skeleton positioning ribs 104.

[0027] Secondly, the high-flowability cement-based slurry 106 contains quartz sand fine aggregate 107, which is 40-70 mesh graded. The slurry has a water-cement ratio ≤0.20 and a flowability ≥180mm.

[0028] Meanwhile, the outer surfaces of the hook-shaped main steel fiber 102 and the micro-segment auxiliary steel fiber 103 are coated with a fiber coupling agent layer 108, which is used to enhance the bonding force between the steel fiber and the cement-based interface.

[0029] In addition, the outer surface of the fiber coupling agent layer 108 is coated with a fiber anti-rust layer 109, which resists cement alkaline corrosion and extends the life of the conductive network.

[0030] Secondly, a layered conductive interface transition layer 110 is cast between the upper and lower surfaces of the substrate body 101 and the three-dimensional conductive network. The layered conductive interface is made of a mixture of slurry and 0.1 vol% carbon nanotubes to improve the wave impedance matching performance.

[0031] Meanwhile, embedded reinforcing mesh 111 is attached to the upper and lower outer surfaces of the layered conductive interface transition layer 110, and the embedded reinforcing mesh 111 is completely embedded in the high-flowability cement-based slurry 106. The embedded reinforcing mesh 111 is stainless steel wire mesh, which effectively improves the bending strength of the basic body and avoids local cracking.

[0032] In addition, the upper and lower outer surfaces of the substrate body 101 are provided with a surface anti-crack fiber mesh 112, which is made of polypropylene, to suppress surface shrinkage cracks of the substrate body 101 and ensure shielding integrity.

[0033] Using an electromagnetically shielded concrete slab with a built-in conductive network according to this embodiment, by setting the substrate body 101, the hook-shaped main steel fibers 102, and the high-flowability cement-based slurry 106, in specific use, the welded skeleton positioning ribs 104 mesh is placed into the substrate body 101, and both ends are fixed to the inner wall of the substrate body 101 to ensure that the mesh is horizontal. The hook-shaped main steel fibers 102 are evenly spread between the skeleton positioning ribs 104 mesh at a dosage of 7-8 vol%. The hook-shaped main steel fibers 102 are formed into a random spatial skeleton by an electromagnetically assisted random distribution device. Then, the skeleton fixing buckles 105 are sleeved at the intersection nodes of the skeleton positioning ribs 104 and the hook-shaped main steel fibers 102 to lock the skeleton shape. The micro-segment auxiliary steel fibers 103 are scattered into the gaps of the hook-shaped main steel fiber 102 skeleton at a dosage of 1 vol%. The mixture is then gently brushed with a soft brush. The micro-segment auxiliary steel fibers 103 ensure that they fill all gaps to form a complete, stretchable, three-dimensional conductive network. A layer of the layered conductive interface transition layer 110 is laid on the upper and lower surfaces of the three-dimensional conductive network. Then, the embedded reinforcing mesh 111 is laid on the outer surface of the layered conductive interface transition layer 110. The high-flowability cement-based slurry 106 mixed with the quartz sand fine aggregate 107 is poured into the substrate body 101 in three layers. After the first layer is poured, the mold vibration device is turned on to assist the slurry filling. The second layer is poured and the vibration is repeated. After the third layer is poured and vibrated, the slurry surface is smoothed with a scraper, and the surface crack-resistant fiber mesh 112 is laid. This completes the preparation of the electromagnetic shielding concrete board with the built-in conductive network. This can stabilize the fiber distribution position, improve the connectivity of the conductive path, effectively avoid secondary radiation interference, and achieve one-time molding of large-size boards through the high-flowability slurry pouring process combined with the pre-constructed skeleton.

[0034] The above-disclosed embodiments are merely preferred embodiments of electromagnetic shielding concrete plates with built-in conductive networks of the present invention. They should not be construed as limiting the scope of the present invention. Those skilled in the art can understand that implementing all or part of the above embodiments and making equivalent changes in accordance with the claims of the present invention still fall within the scope of the present invention.

Claims

1. An electromagnetically shielded concrete slab with a built-in conductive network, comprising a substrate body (101), characterized in that, The substrate body (101) is provided with hook-shaped main steel fibers (102). The hook-shaped main steel fibers (102) are used to build a three-dimensional conductive network in the mold in advance to form an oriented or random spatial skeleton. Micro-segment auxiliary steel fibers (103) are embedded in the gaps between the hook-shaped main steel fibers (102). The hook-shaped main steel fiber (102) has skeleton positioning ribs (104) on both sides. The skeleton positioning ribs (104) are distributed in a horizontal and vertical grid pattern and are interspersed between the hook-shaped main steel fibers (102). High-flowability cement-based slurry (106) is poured into the three-dimensional conductive network.

2. The electromagnetic shielding concrete slab with a built-in conductive network as described in claim 1, characterized in that, A frame fixing buckle (105) is provided between the frame positioning ribs (104).

3. The electromagnetic shielding concrete slab with a built-in conductive network as described in claim 1, characterized in that, The outer surfaces of the hook-shaped main steel fiber (102) and the micro-segment auxiliary steel fiber (103) are coated with a fiber coupling agent layer (108).

4. The electromagnetic shielding concrete slab with a built-in conductive network as described in claim 3, characterized in that, The outer surface of the fiber coupling agent layer (108) is coated with a fiber anti-rust layer (109).

5. The electromagnetic shielding concrete slab with a built-in conductive network as described in claim 4, characterized in that, A layered conductive interface transition layer (110) is cast between the upper and lower surfaces of the substrate body (101) and the three-dimensional conductive network.

6. The electromagnetic shielding concrete slab with a built-in conductive network as described in claim 5, characterized in that, The upper and lower outer surfaces of the layered conductive interface transition layer (110) are fitted with embedded reinforcing mesh (111), and the embedded reinforcing mesh (111) is completely embedded in the high-flowability cement-based slurry (106).

7. The electromagnetic shielding concrete slab with a built-in conductive network as described in claim 6, characterized in that, The upper and lower outer surfaces of the substrate body (101) are provided with a surface anti-crack fiber mesh (112).

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